ELECTRIÇIDADE DE MOÇAMBIQUE (EDM)

THE REPUBLIC OF MOZAMBIQUE

PREPARATORY STUDY
ON
GAS-FIRED POWER PLANT DEVELOPMENT
IN
SOUTHERN MOZAMBIQUE

FINAL REPORT

MARCH 2013

JAPAN INTERNATIONAL COOPERATION AGENCY

TOKYO ELECTRIC POWER SERVICES CO., LTD. (TEPSCO)
ORIENTAL CONSULTANTS CO., LTD. (OC)
IL
CR(3)
13-025
 Project Site

Project Location Map

 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Table of Contents

Location of Study Area

Table of Contents
List of Tables and Figures
Abbreviations
Executive Summary
Main Report
Appendices

Page

Chapter 1 Introduction .............................................................................................................. 1-1

1.1 Background of the study................................................................................................... 1-1
1.2 Purpose of the study ......................................................................................................... 1-1
1.3 Scope of works ................................................................................................................ 1-1
1.4 Organizational framework for the Study ........................................................................... 1-7

Chapter 2 Overview of Power Sector ......................................................................................... 2-1

2.1 Social and Economic Conditions ...................................................................................... 2-1
2.1.1 Land Area and Population ............................................................................................ 2-1
2.1.2 Poverty Incidence ........................................................................................................ 2-1
2.1.3 Mozambique’s Rich Resource ...................................................................................... 2-2
2.1.4 Economic Condition .................................................................................................... 2-3
2.2 Overview of Network System .......................................................................................... 2-7
2.2.1 Network System .......................................................................................................... 2-7
2.2.2 Southern System ......................................................................................................... 2-10
2.2.3 Facilities in the Southern System ................................................................................. 2-11
2.2.4 Power Flow ................................................................................................................ 2-13
2.2.5 Fault Current .............................................................................................................. 2-14
2.3 Power Demand Forecast and Development Plan ............................................................. 2-16
2.3.1 Geographical Scope .................................................................................................... 2-16
2.3.2 Current Supply/demand Status .................................................................................... 2-17
2.3.3 Power Demand Forecast ............................................................................................. 2-20
2.3.4 Power Development Plan ............................................................................................ 2-22
2.4 Outline of Cooperation Projects Implemented by Other Donor Agencies ........................ 2-31
2.4.1 On-going Power Projects ............................................................................................ 2-31
2.4.2 Priority Projects without Funding ................................................................................ 2-32

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2.4.3 Recently Completed Projects ....................................................................................... 2-34

2.4.4 Scale of Project Costs ................................................................................................. 2-34
2.4.5 Assistance to the Mozambican Power Sector by International Aid Agencies ................. 2-36
2.4.6 Assistance to the Mozambican Power Sector by Norway .............................................. 2-37
2.4.7 Assistance to the Mozambican Power Sector by Germany ............................................ 2-37

Chapter 3 Selection of the Site ................................................................................................... 3-1

3.1 Evaluation Criteria ........................................................................................................... 3-1
3.2 Required Area for Power Plant ......................................................................................... 3-3
3.2.1 Setting Conditions for the Layout of the Power Plant for the Candidate Sites ................. 3-3
3.3 Land Preparation and Accessibility ................................................................................... 3-5
3.3.1 Beluluane Site ............................................................................................................. 3-6
3.3.2 CTM Site .................................................................................................................... 3-7
3.4 Topography, Geology and Meteorology ............................................................................ 3-8
3.5 Constraints of a Power System ......................................................................................... 3-9
3.5.1 Three Elements of Constraints ...................................................................................... 3-9
3.5.2 Target System............................................................................................................. 3-10
3.5.3 Base Case ................................................................................................................... 3-10
3.5.4 Reference Case (Based on EDM’s Current Network Expansion Plan) ........................... 3-19
3.6 Fuel Gas Volume Constraints ......................................................................................... 3-28
3.6.1 Fuel Gas Volume Constraints ...................................................................................... 3-28
3.6.2 Gas Supply Contract Constraints ................................................................................. 3-29
3.6.3 Constraints for Environmental and Social Consideration .............................................. 3-29
3.7 Potential CCGT Product ................................................................................................. 3-29
3.8 Comparison of the Candidate Sites ................................................................................. 3-30
3.9 Output from Workshop for Site Selection ....................................................................... 3-31

Chapter 4 Suitable rated power and General Specification ...................................................... 4-1

4.1 Suitable Rated Power ....................................................................................................... 4-1
4.1.1 Study from Supplying fuel gas amount ......................................................................... 4-1
4.1.2 Study from Power Plant Area ....................................................................................... 4-1
4.1.3 Study from GT manufacturer........................................................................................ 4-1
4.2 Power Block Configuration (2-on-1, 1-on-1) .................................................................... 4-2
4.2.1 CCGT Configuration ................................................................................................... 4-2
4.2.2 Main characteristics of CCGT shaft configuration ......................................................... 4-4
4.2.3 The layout of CCGT .................................................................................................... 4-7
4.3 Condenser Cooling System ............................................................................................ 4-13
4.3.1 Outline ....................................................................................................................... 4-13
4.3.2 Mechanical examination of condenser cooling system .................................................. 4-13

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4.3.3 Overall study of water intake facilities ......................................................................... 4-16

4.3.4 Study from viewpoints of economy ............................................................................. 4-18
4.3.5 Overall judgment ........................................................................................................ 4-19
4.3.6 Risk to water intake of development of surrounding sea areas ....................................... 4-20

Chapter 5 Site Conditions .......................................................................................................... 5-1

5.1 Topography and Geology ................................................................................................. 5-1
5.1.1 Topography ................................................................................................................. 5-1
5.1.2 Geology ...................................................................................................................... 5-2
5.2 Meteorological Conditions ............................................................................................... 5-5
5.2.1 General ....................................................................................................................... 5-5
5.2.2 Characteristic of Tropical Cyclones that hit Mozambique .............................................. 5-5
5.2.3 Tropical Storms in Early February ................................................................................ 5-6

Chapter 6 Basic Design............................................................................................................... 6-1

6.1 Design Philosophy ........................................................................................................... 6-1
6.1.1 Project Outline............................................................................................................. 6-1
6.1.2 Operation Requirements ............................................................................................... 6-1
6.1.3 Control and Operation Philosophy ................................................................................ 6-3
6.2 Study of Basic Technical Issues ........................................................................................ 6-5
6.2.1 Expected Performance of the Mozambique Combined Cycle Gas Turbine ..................... 6-5
6.2.2 Exhaust Gas Bypass System ........................................................................................ 6-14
6.2.3 Auxiliary Boiler .......................................................................................................... 6-17
6.2.4 Gas turbine and steam turbine buildings ....................................................................... 6-18
6.3 Scope of Work ............................................................................................................... 6-20
6.3.1 Procurement and/or Manufacture................................................................................. 6-20
6.3.2 Works and Services to be provided by Contractor ........................................................ 6-22
6.3.3 EDM’s construction work and work items ................................................................... 6-26
6.3.4 Terminal Points .......................................................................................................... 6-26
6.4 Plant Design Considerations ........................................................................................... 6-28
6.4.1 Design conditions ....................................................................................................... 6-28
6.4.2 Standards and Criteria ................................................................................................. 6-28
6.4.3 Site Layout ................................................................................................................. 6-29
6.4.4 Environmental Requirements ...................................................................................... 6-33
6.4.5 Gas Turbine ................................................................................................................ 6-35
6.4.6 Heat Recovery Steam Generator .................................................................................. 6-36
6.4.7 Steam Turbine ............................................................................................................ 6-38
6.4.8 Fuel Supply System .................................................................................................... 6-39
6.4.9 Water Treatment System ............................................................................................. 6-40

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6.4.10 Wastewater System..................................................................................................... 6-42

6.4.11 Fire Fighting System ................................................................................................... 6-42
6.5 General Specification of Electrical and Control System .................................................. 6-43
6.6 Civil and Architectural Works ........................................................................................ 6-60
6.6.1 Major Components of Civil and Architectural Works ................................................... 6-60
6.6.2 Earthquakes ................................................................................................................ 6-60
6.6.3 Design Conditions ...................................................................................................... 6-62
6.6.4 Design of Foundations ................................................................................................ 6-64
6.6.5 Architectural Works.................................................................................................... 6-67

Chapter 7 Natural Gas Supply Plan .......................................................................................... 7-1

7.1 Overview of Natural Gas in Mozambique ......................................................................... 7-1
7.2 Gas Supply in the South ................................................................................................... 7-3
7.2.1 Gas Production Volume and Route ............................................................................... 7-3
7.2.2 Gas Supply Volume ..................................................................................................... 7-4
7.2.3 Gas Supply Route in the South ..................................................................................... 7-5
7.2.4 Gas Supply Volume to the Gas-fired Thermal Power Plant in the Southern Region ........ 7-7
7.3 Gas Price ......................................................................................................................... 7-9
7.4 Relationship of Relevant Organization related to Gas Supply and Transport Agreements 7-10
7.5 Scope of Gas Pipeline Work and Tie-in Point.................................................................. 7-12

Chapter 8 Project Implementation Plan .................................................................................... 8-1

8.1 Implementation Schedule in ODA Scheme ....................................................................... 8-1
8.1.1 Project Preparation....................................................................................................... 8-1
8.1.2 Selection of EPC Contractor ........................................................................................ 8-1
8.1.3 Construction................................................................................................................ 8-1
8.2 Construction, Procurement and Transportation ................................................................. 8-3
8.2.1 Present State of Site .................................................................................................... 8-3
8.2.2 Transportation of Heavy Equipment ............................................................................ 8-4
8.2.3 Maputo Ring Road Project .......................................................................................... 8-8
8.2.4 Other Issues for Construction Planning ...................................................................... 8-10
8.3 Points of Concern for Project Implementation ................................................................ 8-10
8.3.1 Procurement in Mozambique ..................................................................................... 8-10
8.3.2 Tendering Method and Contract Conditions ................................................................ 8-11
8.3.3 Selection of a Consultant ............................................................................................ 8-11
8.3.4 Selection of an EPC Contractor .................................................................................. 8-11
8.4 Management at Construction Stage................................................................................. 8-12
8.4.1 Project Implementation Organization......................................................................... 8-12
8.4.2 Construction management ......................................................................................... 8-14
8.5 Management at O&M Stage ........................................................................................... 8-15
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8.5.1 Current State of EDM Capability ............................................................................... 8-16

8.5.2 Reinforcement of Organization Management ............................................................. 8-17
8.5.3 Reinforcement of Cause Analysis Capability ............................................................. 8-18
8.5.4 Reinforcement of Maintenance Implementation System ............................................ 8-27
8.5.5 Reinforcement of Long-term Human Capital Development ....................................... 8-32
8.5.6 Reinforcement of Environment Management Planning and Monitoring ..................... 8-34

Chapter 9 Project Cost ............................................................................................................... 9-1

9.1 Project Cost Estimate ....................................................................................................... 9-1
9.2 EPC Cost ......................................................................................................................... 9-3
9.2.1 Basis of EPC Cost Estimate.......................................................................................... 9-3
9.2.2 Adjustment of Local Portion of EPC Cost ..................................................................... 9-3
9.3 Validity of the Project Cost ............................................................................................... 9-7
9.3.1 Price Trends of Combined Cycle Power Facilities ......................................................... 9-7
9.3.2 Appropriateness of Project Cost ................................................................................... 9-8
9.4 Engineering Services ...................................................................................................... 9-10
9.4.1 Foreign Consultant...................................................................................................... 9-10
9.4.2 Local Consultant......................................................................................................... 9-10
9.5 Operation and Maintenance Costs ................................................................................... 9-11
9.5.1 Operation and Maintenance ......................................................................................... 9-11
9.5.2 Examination of LTSA ................................................................................................. 9-11

Chapter 10 Financial and Economic Analyses ........................................................................... 10-1

10.1 Effectiveness of the Project ............................................................................................ 10-1
10.2 Financial Situation of EDM ............................................................................................ 10-2
10.2.1 Profitability ................................................................................................................ 10-3
10.2.2 Debt Service Capacity................................................................................................. 10-3
10.3 Financial Analysis of the Project .................................................................................... 10-3
10.3.1 Key Assumptions Used for Financial Analysis ............................................................. 10-3
10.3.2 The Unit Cost of Generation of Electricity ................................................................. 10-10
10.3.3 FIRR on the Total Investment Cost (Project FIRR) ..................................................... 10-12
10.3.4 Financial Analysis on the Equity................................................................................ 10-14
10.3.5 Sensitivity to FIRRs .................................................................................................. 10-16
10.3.6 Conclusion on Financial Feasibility ........................................................................... 10-17
10.4 Economic Analysis of the Project ..................................................................................10-17
10.4.1 Key Assumptions Used for Economic Analysis .......................................................... 10-17
10.4.2 EIRR........................................................................................................................ 10-21
10.4.3 Sensitivity Analysis................................................................................................... 10-23
10.4.4 Conclusion on Economic Feasibility .......................................................................... 10-23

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10.5 Operation and Effect Indicators .....................................................................................10-23

Chapter 11 Environmental and Social Considerations .............................................................. 11-1

11.1 Outline of Project Components Subject to Environmental and Social Considerations ....... 11-1
11.1.1 Selection of Proposed Project Site .............................................................................. 11-1
11.1.2 Proposed CCGT Technology ...................................................................................... 11-1
11.1.3 Type of Cooling System ............................................................................................. 11-1
11.2 Baseline Environmental Condition .................................................................................. 11-2
11.2.1 Natural Environment Conditions ................................................................................ 11-2
11.2.2 Socio-economic Conditions ...................................................................................... 11-17
11.3 System and Organization of Environmental and Social Considerations in Mozambique . 11-19
11.3.1 Environmental Laws, Regulations and Standards in Mozambique ............................. 11-19
11.3.2 Environmental Impact Assessment System in Mozambique ...................................... 11-24
11.3.3 Organization Responsible for EIA System in Mozambique ....................................... 11-31
11.3.4 Project Categorization of the Proposed Project ......................................................... 11-34
11.4 Comparison and Study of Alternatives (including Zero Option or Without Project) ........ 11-35
11.4.1 Project Site Selection ............................................................................................... 11-35
11.4.2 Type of Cooling System ........................................................................................... 11-36
11.4.3 Zero Option or Without Project ................................................................................ 11-38
11.5 Scoping and TOR for the Environmental and Social Consideration Study ...................... 11-39
11.5.1 Scoping for Environmental and Social Consideration Issues ..................................... 11-39
11.5.2 TOR for Environmental and Social Considerations Study ......................................... 11-41
11.6 Land Acquisition and Resettlement ............................................................................... 11-43
11.6.1 Land Acquisition ...................................................................................................... 11-43
11.6.2 Resettlement ............................................................................................................ 11-43
11.7 Results of the Environmental and Social Study based on Scoping .................................. 11-43
11.8 Evaluation of Significant Environmental Impacts .......................................................... 11-45
11.8.1 Impact during Construction Phase ............................................................................ 11-45
11.8.2 Impact during Operation Phase ................................................................................. 11-49
11.9 Mitigation Measures and Cost of Implementation .......................................................... 11-69
11.10 Monitoring Plan ............................................................................................................ 11-74
11.11 Stakeholders Meeting and Engagement ......................................................................... 11-75

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List of Tables
Page

Table 1.3-1 Study items ························································································ 1-3

Table 2.1-1 Total Population, Area and Population Density by Province, 2011 ······················ 2-1
Table 2.1-2 Selected Macroeconomic Indicators ·························································· 2-3
Table 2.1-3 Share of Gross Domestic Product by Sector (2001 to 2011) ······························ 2-4
Table 2.1-4 CPI-Authorized Investments in Maputo Province by Sector, 2005-2009 ··············· 2-5
Table 2.1-5 CPI-Authorized Investments in Maputo Province by District, 2005-2009·············· 2-5
Table 2.1-6 Current and Future Industrial Customers for Power Demand in Maputo ··············· 2-7
Table 2.2-1 Details of Transmission Facilities in the Southern System ······························ 2-12
Table 2.2-2 Details of Substation Facilities in the Southern System ································· 2-13
Table 2.2-3 Maximum Power Flow by Voltage Class ·················································· 2-14
Table 2.2-4 Maximum Fault Current by Voltage Class ················································· 2-15
Table 2.3-1 Power Supply/Demand Balance in Mozambique (2007 to 2011) ······················ 2-18
Table 2.3-2 Regional Power Demand (GWh) ···························································· 2-19
Table 2.3-3 Power Purchased from Cahora Bassa HPP················································· 2-20
Table 2.3-4 Supply/Demand Balance in kW (Demand: Base Case) ·································· 2-29
Table 2.3-5 Supply/Demand Balance in kWh (Demand: Base Case) ································ 2-30
Table 2.4-1 On-going Power Projects ····································································· 2-32
Table 2.4-2 Priority Projects Without Any Funding ···················································· 2-33
Table 2.4-3 Recently Completed Projects ································································ 2-34
Table 2.4-4 Total Investment Amount in Power Sector ················································ 2-35
Table 2.4-5 Priority Power Projects without Funds ····················································· 2-35
Table 3.1-1 Survey Items for Selection of Sites for a Power Plant ····································· 3-1
Table 3.2-1 Available Plant Capacity for Fuel ····························································· 3-3
Table 3.2-2 Available Power Output for Land ····························································· 3-4
Table 3.4-1 Topographical, Geological and Meteorological Conditions of the Two
Candidate Sites ··················································································· 3-9
Table 3.5-1 Forecast Demand of the CESUL Project ··················································· 3-10
Table 3.5-2 Main Overloaded Transmission Lines ······················································ 3-13
Table 3.5-3 Fault Currents at the Main Substation ······················································ 3-15
Table 3.5-4 Stability Analysis Results ····································································· 3-18
Table 3.5-5 Results of the Network Analysis ···························································· 3-19
Table 3.5-6 Results of the Power Flow Analysis for EDM’s Current Network Expansion
Plan System (2016) ············································································ 3-21
Table 3.5-7 Results of Fault Current Analysis using EDM’s Current Network Expansion
Plan System (2016) ············································································ 3-23
Table 3.5-8 Results of Stability Analysis under EDM’s Current Network Expansion Plan
System (2016) ·················································································· 3-26

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Table 3.5-9 Conclusion of Analysis Results under EDM’s Current Network Expansion
Plan System (2016) ············································································ 3-28
Table 3.7-1 Major Combined Cycle Power Generation Plants for Beluluane (GT
One-shaft Configuration) ····································································· 3-30
Table 3.7-2 Major Combined Cycle Power Generation Plants for CTM (GT One-shaft
Configuration) ·················································································· 3-30
Table 3.8-1 Comparison of the Candidate Sites ·························································· 3-31
Table 4.1-1 Applicable major CCGT model ································································ 4-1
Table 4.2-1 Type of CCGT configuration ·································································· 4-2
Table 4.2-2 Comparison of performance of CCGT configuration ······································ 4-4
Table 4.2-3 Construction cost of CCGT····································································· 4-5
Table 4.2-4 Feature of Type of CCGT Configuration····················································· 4-6
Table 4.2-5 Feature of Each Case of CCGT ······························································ 4-12
Table 4.3-1 Features of Condenser Cooling Systems ··················································· 4-13
Table 4.3-2 Comparisons of intake facilities ····························································· 4-17
Table 4.3-3 Feature of condenser cooling system ······················································· 4-19
Table 4.3-4 Overall judgment of steam turbine condenser cooling system ·························· 4-20
Table 5.1-1 Results of standard penetration test ··························································· 5-4
Table 6.1-1 Requirement unit starting hours of each mode ·············································· 6-2
Table 6.1-2 Requirement Plant Start Times for Design ··················································· 6-3
Table 6.1-3 Shaft Vibration Limits··········································································· 6-5
Table 6.2-1 Performance of Applicable GT Model························································ 6-6
Table 6.2-2 Performance of Applicable CCGT Model ··················································· 6-8
Table 6.2-3 New Models for 30 – 40 MW ································································ 6-14
Table 6.2-4 Summary of GT Exhaust Gas Bypass System ············································· 6-17
Table 6.2-5 GT and Steam Turbine Facilities With and Without Buildings ························· 6-18
Table 6.4-1 Design conditions ·············································································· 6-28
Table 6.4-2 Emission Limits of Pollutants ································································ 6-33
Table 6.4-3 Noise Standards ················································································ 6-33
Table 6.4-4 Effluent Standards ············································································· 6-34
Table 6.4-5 HRSG Circulation Comparison ······························································ 6-37
Table 6.4-6 Gas Flow Orientation Comparisons ························································· 6-38
Table 6.4-7 Gas Properties ·················································································· 6-40
Table 6.4-8 List of protected areas and fire fighting and detection systems types ·················· 6-42
Table 6.5-1 Generator specifications ······································································ 6-44
Table 6.5-2 Transformer specifications ··································································· 6-47
Table 6.5-3 Generator protection relays ··································································· 6-51
Table 6.5-4 Generator step-up transformer protection relays ·········································· 6-52
Table 6.5-5 Auxiliary transformer protection relays ···················································· 6-52
Table 6.6-1 Rainfall intensity for various return periods ··············································· 6-63
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Table 6.6-2 Design conditions ·············································································· 6-65

Table 6.6-3 Specifications of major buildings for the Project (draft) ································· 6-67
Table 7.1-1 Development and Production Areas in the Rovuma Basin and Mozambique
Basin ······························································································· 7-2
Table 7.3-1 Gas price··························································································· 7-9
Table 8.2-1 List of Berths at Port Maputo ·································································· 8-5
Table 8.4-1 Role of PIU and Engagement Period ······················································· 8-16
Table 8.5-1 Functions between HQ and PS ······························································· 8-18
Table 8.5-2 Datasheet for Analyzing Unscheduled Outages ··········································· 8-27
Table 8.5-3 Analysis Sheet of Unplanned Stoppage Trouble: Preventive Measures of
Reoccurrence ··················································································· 8-28
Table 8.5-4 Direction of Maintenance Implementation System ······································· 8-29
Table 8.5-5 Specific Environmental Preservation Measures ··········································· 8-36
Table 9.1-1 Project Cost Estimate ············································································ 9-2
Table 9.2-1 Africa Building Cost Rate Comparison······················································· 9-4
Table 9.2-2 Building Cost per square meter in South Africa ············································ 9-5
Table 9.2-3 Building Cost per square meter in America ·················································· 9-6
Table 9.3-1 List of contracted amount of EPC construction ············································· 9-9
Table 9.5-1 Inspection Interval by Type (Example) ····················································· 9-11
Table 9.5-2 Characteristics of LTSAs ····································································· 9-13
Table 10.2-1 Financial Statements and Indicators························································· 10-2
Table 10.3-1 Changes in Consumer-Price Inflation (%) ················································· 10-4
Table 10.3-2 Changes in the Average Annual Exchange Rate between Metical and USD ········· 10-4
Table 10.3-3 Cost among the Years of Construction ····················································· 10-5
Table 10.3-4 Cost among Foreign and Local Currency Components: ································· 10-5
Table 10.3-5 Initial Investment Costs ······································································· 10-5
Table 10.3-6 Average Electricity Sales Price Analysis ··················································· 10-6
Table 10.3-7 Annual O&M Costs············································································ 10-7
Table 10.3-8 Disbursement of Investment Costs and Flow of Financial Resources ················· 10-8
Table 10.3-9 Projected Cash Flow before Debt Service (operation period) 2018-2042 ·········· 10-9
Table 10.3-10 Generation Cost ·············································································· 10-11
Table 10.3-11 Project FIRR (2014-2042) ································································· 10-13
Table 10.3-12 Cash Flow Table for Financial Planning (operation period) 2017-2042 ············ 10-15
Table 10.3-13 Results of Sensitivity Analysis on FIRR ················································· 10-16
Table 10.4-1 Conversion Factor for Economic Costs ·················································· 10-21
Table 10.4-2 EIRR of the Project (2014-2042) ··························································· 10-22
Table 10.4-3 The Results of EIRR Sensitivity Analysis ················································ 10-23
Table 10.5-1 Operation and Effect Indicators ····························································· 10-24
Table 11.2-1 Air quality sampling methods································································ 11-6
Table 11.2-2 Daily Ambient Concentrations for PM10, SO2 and NO2·································· 11-7
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Table 11.2-3 Noise monitoring coordinates ································································ 11-9

Table 11.2-4 Noise levels at each monitoring points ···················································· 11-10
Table 11.2-5 Noise level at MP11* ········································································ 11-10
Table 11.2-6 Monitoring results in 11 monitoring points ··············································· 11-12
Table 11.2-7 Water quality at monitoring points ························································· 11-16
Table 11.2-8 Population in Ka Mubukwana District, 2007············································· 11-17
Table 11.3-1 Environmental regulations in Mozambique ·············································· 11-20
Table 11.3-2 Air quality standards in Mozambique ····················································· 11-21
Table 11.3-3 Standards of emission for airborne pollutants by thermal power stations ··········· 11-21
Table 11.3-4 Standards of potentially harmful substances ············································· 11-21
Table 11.3-5 Ambient air quality standards for PM10 parameter ······································ 11-22
Table 11.3-6 Dust-fall criteria ··············································································· 11-22
Table 11.3-7 WHO ambient air quality guidelines ······················································ 11-23
Table 11.3-8 IFC ambiant noise level guidelines ························································ 11-23
Table 11.3-9 IFC Effluent Guidelines ····································································· 11-24
Table 11.3-10 Licensing and fees ············································································ 11-25
Table 11.3-11 Schedule of decision-making, by project category ······································ 11-26
Table 11.3-12 Comparison of environmental and social considerations by JICA, ADB and
Mozambique ··················································································· 11-29
Table 11.3-13 Tentative schedule of official EIA process of the proposed project ·················· 11-34
Table 11.4-1 Summarized results of the comparative study on site selection························ 11-35
Table 11.4-2 Summarized results of the comparative study on cooling system ····················· 11-37
Table 11.5-1 Items in the environmental checklist ······················································ 11-39
Table 11.5-2 Draft scoping of environmental impact ··················································· 11-40
Table 11.5-3 TOR for environmental and social consideration study ································ 11-42
Table 11.7-1 Results of the environmental and social study based on scoping ····················· 11-43
Table 11.8-1 Environmental impact matrix ······························································· 11-46
Table 11.8-2 Measurement cases of atmospheric pollutants ··········································· 11-51
Table 11.8-3 Emissions specifications ····································································· 11-53
Table 11.8-4 Monthly ambient temperature ······························································ 11-54
Table 11.8-5 Monthly humidity ············································································· 11-54
Table 11.8-6 Annual occurrence ratio by wind speed/wind direction (2009–2011) ················ 11-55
Table 11.8-7 Monthly wind direction occurrence ratio (2009–2011) ································· 11-55
Table 11.8-8 Monthly average wind speed by wind direction (2009–2011) ························· 11-56
Table 11.8-9 Condition of the stability and wind speed ················································· 11-58
Table 11.8-10 Pasquill stability categories ·································································· 11-58
Table 11.8-11 Prediction Result of the Maximum Future Concentration at the Ground Level
of NO2 under the Normal Conditions Resulting from Installation of New
CCGT (1 Hour Value) ······································································· 11-62

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Table 11.8-12 Prediction Result of the Maximum Future Concentration at the Ground Level
under the Special Conditions Resulting from Installation of New CCGT (1
Hour Value) ···················································································· 11-65
Table 11.9-1 Mitigation measures during construction phase ·········································· 11-70
Table 11.9-2 Mitigation measures during operation phase ············································· 11-72
Table 11.10-1 Environmental monitoring plan during construction phase ····························· 11-74
Table 11.10-2 Environmental Monitoring during operation phase ······································ 11-75

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List of Figures
Page

Figure 1.3-1 Target area ························································································· 1-2

Figure 1.3-2 Overall study flow ················································································ 1-5
Figure 1.3-3 Study schedule ···················································································· 1-6
Figure 1.4-1 JICA Study Team ················································································· 1-7
Figure 2.1-1 Poverty Headcount (%) ·········································································· 2-2
Figure 2.2-1 Network System Diagram ······································································· 2-9
Figure 2.2-2 The Southern System and Transmitting Capacity of Transmission Lines ············· 2-11
Figure 2.2-3 Power Flow in 2011 (Unit: MW) ···························································· 2-14
Figure 2.2-4 Fault Current in 2011 (Unit: kA) ····························································· 2-15
Figure 2.3-1 Regional Power Systems in Mozambique ·················································· 2-17
Figure 2.3-2 Load Profile for Maximum Daily Demand (November 16, 2011) ······················ 2-18
Figure 2.3-3 Power Supply Structure in the Southern Regional System······························· 2-19
Figure 2.3-4 Regional Demand Forecast by Base Case ·················································· 2-21
Figure 2.3-5 Southern Region’s Demand Forecast by Development Case ···························· 2-21
Figure 2.3-6 Northern/Central Regions’ Supply/Demand Balance in kW (Demand: Base) ········ 2-24
Figure 2.3-7 Southern Regions’ Supply/Demand Balance in kW (Demand: Base) ·················· 2-24
Figure 2.3-8 Southern Region’s Supply/Demand Balance in kW (Demand: Low) ·················· 2-25
Figure 2.3-9 Northern/Central Regions’ Supply/Demand Balance in kWh (Demand: Base) ······ 2-26
Figure 2.3-10 Southern Region’s Supply/Demand Balance in kWh (Demand: Base) ················· 2-27
Figure 2.3-11 Southern Region’s Supply/Demand Balance in kWh (Demand: Low) ················· 2-28
Figure 2.4-1 Breakdown of Priority Power Projects without Funding ································ 2-36
Figure 3.2-1 Beluluane Site ····················································································· 3-4
Figure 3.2-2 CTM Site··························································································· 3-5
Figure 3.3-1 Location of CTM Maputo & Beluluane Sites and Access Route from Port Maputo ············ 3-6
Figure 3.3-2 Access from the Front Road at Beluluane Site··············································· 3-7
Figure 3.3-3 Access from the Front Road at CTM Site ···················································· 3-8
Figure 3.5-1 Network System of the Southern Gas-Fired Power Plant ································ 3-11
Figure 3.5-2 Interconnected Power System at Beluluane ················································ 3-12
Figure 3.5-3 Power Flow Analysis Results (2017) ························································ 3-15
Figure 3.5-4 Fault Current Analysis Results (2017) ······················································ 3-17
Figure 3.5-5 Fluctuation Curve of Generator Voltage Angle ············································ 3-18
Figure 3.5-6 System of EDM’s Current Network Expansion Plan (2016) ···························· 3-20
Figure 3.5-7 Results of Power Flow Analysis using EDM’s Current Network Expansion
Plan System (2016) ············································································ 3-22
Figure 3.5-8 Results of Fault Current Analysis using EDM’s Current Network Expansion
Plan System (2016) ············································································ 3-25

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Figure 3.5-9 The Fluctuation Curves of Generator Voltage Angles under EDM’s Current
Network Expansion Plan System (2016) ··················································· 3-27
Figure 3.6-1 Location of Gas Station and Gas Pipeline Route ········································· 3-29
Figure 4.2-1 Type of CCGT configuration ··································································· 4-3
Figure 4.2-2 An example of a 50 MW class CCGT Plant Layout ········································ 4-7
Figure 4.2-3 An example of a CCGT Layout at the Beluluane site······································· 4-8
Figure 4.2-4 Typical CCGT Layout of a heavy duty GT··················································· 4-9
Figure 4.2-5 Typical CCGT Layout of an aero-derivative GT ············································ 4-9
Figure 4.2-6 Plant Layout (Case 1) ·········································································· 4-10
Figure 4.2-7 Plant Layout (Case 2) ·········································································· 4-11
Figure 4.2-8 Plant layout (Case 3) ··········································································· 4-12
Figure 4.3-1 Schematic diagram of cooling system ······················································· 4-15
Figure 4.3-2 Water intake facilities for the old Maputo coal-fired power plant ······················ 4-16
Figure 4.3-3 Intake facilities (conceptual drawing) ······················································· 4-16
Figure 4.3-4 Intake facilities (conceptual drawing) ······················································· 4-17
Figure 4.3-5 Assessment of soundness of existing intake facilities ···································· 4-18
Figure 4.3-6 Schematic Diagram of Cooling System ····················································· 4-19
Figure 4.3-7 Sea area development around project site ·················································· 4-20
Figure 5.1-1 Topographical situation around CTM Maputo ··············································· 5-1
Figure 5.1-2 Geological setting around the Project site ···················································· 5-2
Figure 5.1-3 Location of boreholes ············································································ 5-3
Figure 5.2-1 Cyclone frequency and paths ··································································· 5-5
Figure 5.2-2 Satellite image showing the progression of the first tropical depression that hit
Mozambique in early February ································································ 5-6
Figure 5.2-3 Daily precipitation recorded at Maputo City from February 3 to 7, 2000 ··············· 5-7
Figure 6.1-1 Operation time limitation ········································································ 6-4
Figure6.2-1 Ambient Temperature Performance Characteristics Curve ································· 6-9
Figure 6.2-2 Heat Balance Diagram of 2 x LM6000PD Sprint at the rated site conditions
performance ···················································································· 6-10
Figure 6.2-3 Heat Balance Diagram of 2 x LM6000PD Sprint at the maximum capacity site
conditions ······················································································· 6-11
Figure 6.2-4 Heat Balance Diagram of 2 x H-25 at the rated site conditions performance ········· 6-12
Figure 6.2-5 Heat Balance Diagram of 2 x H-25 at the maximum capacity site conditions ········ 6-13
Figure 6.2-6 GT Package ······················································································ 6-19
Figure 6.3-1 Terminal Point ·················································································· 6-27
Figure 6.4-1 Plant Layout ····················································································· 6-30
Figure 6.4-2 Example of Gas Turbine and HRSG························································· 6-31
Figure 6.4-3 Example of Steam Turbine with Air Cooled Condenser ································· 6-32
Figure 6.4-4 Water Treatment Flow (Water Balance) ···················································· 6-41
Figure 6.5-1 Outline of electrical system ··································································· 6-44
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Figure 6.5-2 Key Single Line Diagram - 1 ································································· 6-48

Figure 6.5-3 Key Single Line Diagram – 2································································· 6-49
Figure 6.5-4 GIS layout and connection point ····························································· 6-54
Figure 6.5-5 Outline of Plant Control ······································································· 6-56
Figure 6.6-1 Seismicity of Eastern and Southern African Regions ····································· 6-61
Figure 6.6-2 Distribution of the expected peak horizontal ground acceleration (possibility
of 10% within 50 years) ······································································ 6-61
Figure 6.6-3 Relationship between tidal levels and ground level of the site ·························· 6-62
Figure 6.6-4 A photo showing installation of the existing oil tanks (in 1970s) ······················· 6-64
Figure 6.6-5 Outline drawing for foundation of gas turbine ············································· 6-66
Figure 6.6-6 A drainage channel parallel to railway (70 cm wide) and a storm drain in
CTM Maputo ··················································································· 6-68
Figure 6.6-7 Existing drainage system in and around the CTM Maputo ······························ 6-69
Figure 7.1-1 Gas Fields in Mozambique ····································································· 7-1
Figure 7.1-3 Investment in the Oil and Gas Sector ·························································· 7-3
Figure 7.2-1 TemaneSecunda Gas Pipeline Route ························································· 7-4
Figure 7.2-2 MGC Gas Pipeline Route ······································································· 7-5
Figure 7.2-3 Existing Gas Pipeline Network (green) in Matola City····································· 7-6
Figure 7.2-4 Preparation Work of New Pipeline Linking MGC Pipeline and CTM
Maputo (ENH/KOGAS) ········································································ 7-6
Figure 7.2-5 Route of New Pipeline Linking MGC Pipeline and CTM Maputo
(ENH/KOGAS) ·················································································· 7-7
Figure 7.2-6 Pipeline Route near CTM Maputo and Location of Pressure Reducing
Station in CTM Maputo ········································································ 7-7
Figure 7.2-7 Overall Gas Flow Schematic in the Southern Region ······································ 7-8
Figure 7.2-8 Organization Structure for Gas Production and Pipeline Operations of
Pande-Temane Gas Fields ······································································ 7-9
Figure 7.4-1 Gas Supply & Transport Concept to EDM ················································· 7-11
Figure 8.1 1 Project Implementation Schedule ······························································ 8-2
Figure 8.2 1 Overhead View of CTM Maputo Site ························································· 8-3
Figure 8.2 2 Transportation Route from Port Maputo to CTM Maputo Site ···························· 8-6
Figure 8.2 3 Crossover-1 ························································································ 8-7
Figure 8.2 4 Crossover-2 ························································································ 8-7
Figure 8.2 5 General View of Maputo Ring Road Plan ····················································· 8-8
Figure 8.2 6 Assumption of the Route of Section 6 and the Location of CTM Maputo Site ········· 8-9
Figure 8.2 7 Assumed Route of Section 6 and Interference with the CTM Maputo Site ············· 8-9
Figure 8.4 1 PIU in EDM ····················································································· 8-12
Figure 8.4 2 Organization of PIU ············································································ 8-13
Figure 8.5 1 Organization of O&M Management Flow ·················································· 8-16
Figure 8.5 2 Organization of O&M Management Flow ·················································· 8-18
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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Figure 8.5 3 Conceptual Figure of Maintenance Management (By Level) ···························· 8-20
Figure 8.5 4 Standard Management Flow Based on PDCA ············································· 8-21
Figure 8.5 5 Heinrichs Principle Disaster Pyramid ······················································· 8-22
Figure 8.5 6 Environmental Management Systems (Plant Level) ······································ 8-34
Figure 8.5 7 Environmental Management System (Public Level) ······································ 8-36
Figure 9.3-1 Price trend of combined cycle power facilities ·············································· 9-7
Figure 9.3-2 Proportion of Equipment FOB Price in EPC Cost··········································· 9-8
Figure 10.4-1 Average Sales Price of Electricity and Willingness to Pay ···························· 10-19
Figure 11.2-1 Average monthly highest and lowest temperatures at Station No. 64
(2009–2011) ···················································································· 11-2
Figure 11.2-2 Average monthly humidity at station No. 64 (2009–2011) ···························· 11-3
Figure 11.2-3 Average monthly solar radiation at Station No. 64 (2009–2011) ···················· 11-3
Figure 11.2-4 Wind rose for Maputo at Station No. 64 (2007–2011) ································· 11-4
Figure 11.2-5 Wind class frequency distribution at Station No. 64 (2007–2011) ·················· 11-4
Figure 11.2-6 Monthly rainfall, Maputo 2007–2011 ····················································· 11-5
Figure 11.2-7 Location of air quality monitoring points ················································ 11-6
Figure 11.2-8 Typical sound levels (dB(A))······························································· 11-8
Figure 11.2-9 Location of noise monitoring points ······················································ 11-9
Figure 11.2-10 Average noise level at MP11 over 9 days period (Nov 23–Dec 01/2012) ········· 11-11
Figure 11.2-11 Location of water quality monitoring points ··········································· 11-15
Figure 11.3-1 Schematic presentation of the EIA process in Mozambique ························· 11-27
Figure 11.3-2 Organization structure of MICOA ························································ 11-33
Figure 11.8-1 Wind rose (Average from 2009 to 2011) ················································ 11-56
Figure 11.8-2 Wind rose (2009–2011) ···································································· 11-57
Figure 11.8-3 Prediction Result of the Maximum Concentration at the Ground Level of
NO2 under the Normal Conditions Resulting from Installation of New CCGT
(1 Hour Value) for Atmospheric Stabilities A and B ··································· 11-60
Figure 11.8-4 Prediction Result of the Maximum Concentration at the Ground Level of
NO2 under the Normal Conditions Resulting from Installation of New CCGT
(1 Hour Value) for Atmospheric Stabilities C and D ··································· 11-61
Figure 11.8-5 Predicted Concentration Distribution Chart of NO2 (Southwest Wind,
Stability A, Wind Speed 1.0 m/s) ·························································· 11-63
Figure 11.8-6 Predicted Concentration Distribution Chart of NO2 (Southwest Wind,
Stability B, Wind Speed 4.0 m/s) ·························································· 11-63
Figure 11.8-7 Predicted Concentration Distribution Chart of NOx (Southwest wind,
Maximum Level at the Stability Level, C-1 Hour Value) ······························ 11-64
Figure 11.8-8 Predicted Concentration Distribution Chart of NOx (Southwest Wind,
Maximum Level at the Stability Level, D-1 Hour Value) ······························ 11-64

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Figure 11.8-9 Prediction Result of the Maximum Future Concentration at the ground level
of NO2 under the Special Conditions Resulting from Installation of New
CCGT (1 Hour Value) ······································································· 11-66
Figure 11.11-1 Participants from the Heads of 10 Houses, Urban Blocks 40 and 40a ············· 11-76
Figure 11.11-2 Participants from the Companies and Institutions adjacent to the Site ············· 11-76

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Abbreviations
Abbreviation English Original Language
(Portuguese language)
ACC Air Cooled Condenser
ADB Asian Development Bank
AdeM Águas de Moçambique
AFD French Development Agency L'Agence Française de Développement
AGFUND Arab Gulf Programme for Development
ANE National Roads Administration Administração Nacional de Estradas
APFR Automatic power factor regulator
AQR Automatic reactive power regulator
ASME American Society of Mechanical Engineers
ASTM American Society of Testing and Materials
AVR Automatic voltage regulator
BCF Billion cubic feet
BCP Boiler circulating pumps
BDM Break down maintenance
BOP Balance of Plant
BS British Standards
C/P Counterpart
CBM Condition based maintenance
CCR Central Control Room
CCGT Combined Cycle Gas Turbines
CCTV Closed-circuit television
CEMS Continuous Emission Monitoring System
CF Conversion Factor -
CLDC Central load dispatching center
Mozambican Hydrocarbon Company
CMH Companhia Moçambicana de Hidrocarbonetos
(no official English name)
COD Commercial operation date
CPF Central Processing Facility
CPI Investment Promotion Centre Centro de Promocao de Investimentos
CPU Central Processing Unit
CTM Maputo Thermal Power Station Central Térmica de Maputo
DCS Distribution control system
DIN German standards Deutsches Institut fur Normung
DLP Defect Liability Period
Provincial Directorate for Co-ordination of
DPCA Provinciais para Coordenação da Acção Ambiental
Environmental Affairs
DSCR Debt Service Coverage Ratio -
DSR Debt Service Ratio
Mozambican Electricity Company
EDM Electricidade de Moçambique
(no official English name)
EIA Environmental Impact Assessment
EIRR Economic Internal Rate of Return
EIS Environmental Impact Study
EIB European Investment Bank
Empresa Nacional de Hidrocarbonetos de
ENH Mozambican National Hydrocarbon Company Moçambique
EOH Equivalent operation hours
Engineering, Procurement and Construction
EPC
(contract)
Environmental Pre-Feasibility Study and Scope Estudo de Pré-Viabilidade Ambiental e Definição do
EPDA
Definition Âmb
EPRi Electric Power Institute, Inc.
ESIA
Environmental and Social Impact Assessment
EU European Union
FCT Fault clearing time

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Original Language
Abbreviation English
(Portuguese language)
FDI Foreign Direct Investment
FIDIC International Federation of Consulting Engineers Fédération Internationale Des Ingénieurs-Conseils
Fundo de Investimento e Património de
FIPAG Water Supply Investment and Assets Fund
Abastecimento de Água
FIRR Financial Internal Rate of Return
FOB Free on board
FS Feasibility Study
Mozambican National Rural Electrification Fund
FUNAE Fundo de Energia
(no official English name)
GDP Gross Domestic Product
Deutsche Gesellschaft für Internationale
GIZ German Agency for International Cooperation
Zusammenarbeit
GMCB Generator main circuit breakers
GNI Gross National Income
GoM Government of Mozambique
GOV Governor control unit
GPS Global positioning system
GS Gas Station
GSA Gas Sales Agreement
GT Gas Turbine
HCB Cahora Bassa Hydroelectric Hidroeléctrica de Cahora Bassa
HHV Higher Heating Value -
HQ Head office
HRSG Heat Recovery Steam Generator
JIS Japanese Industrial Standard
I&C Instrumentation and control
I/O Input/ output
IDA International Development Association
IDC Interest During Construction
IFC International Financial Corporation
INAHINA National Institute of Hydrography and Navigation Instituto Nacional de Hidrografia e Navegação
INP National Petroleum Institute Institudo Nacional de Petróleos
IPP Independent Power Producer
JICA Japan International Cooperation Agency
JIS Japanese Industrial Standards
L1, L2, L3 Line bus
LAN Local area network
LC Local Currency -
LCD Liquid Crystal Display
LHV Lower Heating Value
LCOE Levelised Cost of Electricity
LTPM Long Term Parts Management
LTSA Long Term Service Agreement
MCC Motor control center
MDF Main distributing frame
ME Ministry of Energy
MGC Matola Gas Company
MGJ Million gigajoules
MICOA Ministry of Coordination of Environmental Affairs Ministério para Coordenação de Acção Ambiental
MMR Ministry of Mineral Resources
MOH
MPDC Maputo Port Development Company
MSL Mean Sea Level
MUSD Millions of US Dollars
MZN Mozambique Metical
N Neutral bus
NEDAP National Energy Development and Access Program

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Original Language
Abbreviation English
(Portuguese language)
NGV Natural Gas Vehicle
NGO Nongovernmental Organization
NOK Norwegian Krone
Government of Norway Agency for Development
NORAD
Cooperation
NPFA National Protection Fire Association
O&M Operation and Maintenance
OC Oriental Consultants Co., Ltd.
ODA Official Development Assistance
OEL Over excitation limiter
OEM Original equipment manufacturers
OH Overhaul
OJT On the job training
ONAF Oil natural air forced
ONAN Oil natural air natural
PDCA Plan-do-check-act
PDCA Provincial Directorate for Environmental Affairs
PIP Project implementation procedure
PIU Project Implementation Unit
PM Particulate matter
PMU Project Management Unit
POED Project for Entrepreneurial Development
PPA Petroleum Production Agreement
PQ Product quality
PRS Pressure Reduction Station
PS Power station
PSA Production Sharing Agreement
PSS Power system stabilizer
PSS/E Power System Simulator for Engineering
PVB Private branch exchange
Republic of Mozambique Pipeline Investments
ROMPCO
Company Ltd.
RSA Republic of South Africa
SA Surge arrestor
SADC Southern African Development Community
SAPP Southern African Power Pool
SBU Strategic Business Unit
SCADA Supervisory Control and Data Acquisition
SEIA Simplified Environmental ImpactAssessment
SER Simplified Environmental Report
Swedish International Development Cooperation
SIDA
Agency
SOAPP State of the Art Power Plant
SPI Sasol Petroleum International Ltd.
SPT Sasol Petroleum Temane Limitada
ST Steam turbine
Mozambique Regional Transmission Backbone Projecto Regional de Transporte de Energia,
STE
Project Centro-Sul
SUS Steel Use Stainless
TAC Technical Assessment Commission
TBM Time-based maintenance
TCF Trillion cubic feet
TEPSCO Tokyo Electric Power Services Co., Ltd.
TFD Time of Flight Diffraction
TOR Terms of Reference
TQM Total quality management
UAT Unit auxiliary transformer

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Original Language
Abbreviation English
(Portuguese language)
UEL Under excitation limiter
UPS Uninterrupted power supply
USD US dollars
USGS U.S. Geological Survey
UT Ultrasonic Testing
VAC Volts alternating current
VAT Value Added Tax
VCB Vacuum circuit breaker
VDC Volts direct current
VT Voltage transformer
WACC Weighted Average Cost of Capital
WB World Bank
WHO World Health Organisation
WTP Willingness-to-pay
XLPE Cross-linked polyethelene

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Appendices

Appendix1 ：Drawings for Power Plant Layout

Appendix2 ：Terms of Reference (TOR) of Engineering Consultancy Services
Appendix3 ：Site Survey
Appendix4 ：Geological & Geotechnical Survey
Appendix5 ：Environmental and Social Study
Appendix6 ：Records of Discussion during Stakeholders Meeting
Appendix7 ：Environmental Checklist
Appendix8 ：Itinerary for the First Site Survey
Appendix9 ：Itinerary for the Second Site Survey
Appendix10 ：List of Key Persons whom the Survey Team Met
Appendix11 ：List of Collected Data and Information
Appendix12 ：Minutes of Meeting of the 1st Mission
Appendix13 ：Minutes of Meeting of the 2nd Mission

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

EXECUTIVE SUMMARY

1． Background and Purpose of the Study

The purpose of this “Preparatory Study on Gas-Fired Power Plant Development in
Mozambique” is to prepare an approximate design and a Feasibility Study (“FS”) for the
gas-fired combined cycle power plant building project for which the Republic of Mozambique
(“Mozambique”) requests Japanese Official Development Assistance (“ODA”) and to make the
necessary investigations for the examination in order to execute it as a Japanese onerous fund
cooperation project. The background of this study is as follows:
 In 2011, the nationwide power demand of Mozambique was only 616 MW of the
maximum generating capacity of 4,068 GWh/year of gross power production, however
there has been remarkable growth in the annual average increase power rates in the past 5
years, i.e., 14.1% in maximum generating capacity and 11.6% in gross power production.
In particular, the maximum generating capacity in only Southern Mozambique is 369 MW
which is 60% of the 616 MW nationwide power demand mentioned above noting that the
annual average increase rate is showing steady growth.
 Although Electricidade de Mozambique (“EDM”) is making efforts to ensure power supply
capacity, e.g., rehabilitation of old small-scaled hydroelectric and thermal power plants,
purchase of electric power from independent power producers (“IPP”) of power supply
being built in the Ressano Garcia area, and capital participation in IPP, the urgent issue to
satisfy mid- and long-term power demand is to ensure a new power supply for Maputo, the
capital of Mozambique.
 Based on such background, the Mozambique government requested Japanese ODA from
the Japanese government in January, 2012, to support building a gas-fired combined cycle
power plant in Southern Mozambique (50MW capacity).

2． Overview of Power Sector

An overview of the power sector of Mozambique is summarized as follows:
 The means of power supply is divided into three categories: the national grid, mini grids, and
independent systems. For the national grid, EDM is responsible under the supervision of ME.
And for mini grids, the Ministry of Energy (“ME”) is responsible through relevant offices in
provincial governments.
 Since Mozambique has a large geographical area extending 2,000 km from north to south,
the network system is separated into two systems: one for the southern area and the other for
the central and northern areas. These systems are independently operated, without being
linked to each other.

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

 The Cahora Bassa Hydroelectric Power Plant (“HCB”) with an output of 2,075 MW, the
major power source in Mozambique, is linked to the network for the central and northern
areas. A part of the generated power is transmitted to the central and northern areas by means
of a 220 kV AC transmission line and the power supplied meets the load of these areas.
Power is also sent to a neighboring country, Zimbabwe, by means of a 400 kV AC
transmission line. However, the majority of the power generated by HCB is sent to the
Apollo substation in South Africa by a 535 kV DC transmission line and it is then sent to the
Southern African Power Pool (“SAPP”).
 Since the system for the southern area, which covers Maputo, is located over 1,000 km from
HCB, power is imported from SAPP via the networks of South Africa and Swaziland by
means of a 400 kV AC transmission line. As a result, more than 80% of domestic demand is
supplied by re-imported power.
 EDM has been conducting an update study to the existing study, “Mozambique Electricity
Master Plan Study”, which was completed in 2004. The update study, “Update of Master
Plan 2010-2027”, is scheduled to be completed by April 2013. Based on the update of the
master plan, it is expected that the power supply plan for supply stable power will get off the
drawing board.

3． Selection of the Site

Selection of the site is summarized as follows:
 Each candidate site has been carefully compared and assessed from technological and
economical viewpoints, and the best-suited planned construction site was selected,
estimating the approximate scale of the power plant facility. The selected candidate sites
were the Beluluane industrial complex, which EDM had been studying, and a site on the
CTM premises from which a coal-fired power plant had been removed.
 The following three points were considered, in respect of the views of EDM, as prerequisites
for the comparison and study:
(i) Output of the CCGT power station should be maximized so that the contracted gas
volume of 6 MGJ/ year can be fully used, considering that the gas contract is a
take-or-pay contract.
(ii) The existing GT power station in CTM will perform base operations from 2013 to
2017 (when the CCGT power station is expected to start operation), using the
contracted gas volume of 6 MGJ/ year.
(iii)From 2017, the CCGT power station will be in full operation and the GT power
station of CTM will operate only in the case of an emergency, e.g., if the CCGT
power station stops.
 In selecting a power plant construction site, the necessary layout of the site area, current
situation, accessibility, topography, geology, and weather conditions of the site, constraints

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

of the system, fuel supply constraints, condenser cooling method, and selectivity of CCGT
equipment were objectively and comprehensively compared and studied.
 As a result, the CTM site was selected as the project site for a power plant up to 100 MW.
The major determining factor was transmission network capacity constraint.

4． Suitable Rated Power and General Specification

The suitable rated power and general specifications are summarized as follows:
 CCGT capacity is restricted by the amount of natural gas fuel that will be supplied. Since
the gas supply amount to the new gas-fired power plant will be 6.0 MGJ/year, the power
plant capacity is calculated at approximately 114 MW.
 For CCGT rated capacity, the CCGT range for selection can be expanded by making a
setting with a margin of 70-110 MW and the promotion of proper and active competition
bidding among EPC contractors.
 The related power generation plant will be built in southern Maputo city in Mozambique to
cope with the tight power demand in Mozambique. For this plant, one unit operation is
assumed for the present and continuous operation of the power plant with as high efficiency
as possible is required. Globally, in the case of plants that require high efficiency operation
and high capacity factor, multi-shaft 2 and more-on-1 CCGTs are installed. The JICA Study
Team recommends a multi-shaft 2-on-1 CCGT since it is superior in the total efficiency of
the power plant and it will allow partial load operation with high efficiency of about 50%
even if a GT stops because of periodic maintenance, etc., and it has maintenance costs.
 As a result of comparing and studying the three types of cooling systems for an ST cooling
system, i.e., once-through cooling system, wet type cooling tower system, and air-cooled
condenser system, the conclusion was reached that the air-cooled condenser cooling system
is the most suitable for this site, from the economic point of view.

5． Site Conditions
The meteorological, geological and topographical characteristics regarding the project site are
summarized as follows:
 The ground level of the site was raised by 1.5 to 2.0 meters when the former coal-fired
power plant was constructed in the 1950s, and the present ground level is approximately 3.3
m above mean sea level (“M.S.L.”) of Port Maputo.
 Since the embankment of the highway (EN2) located to the north acts as a topographic
divide, rain that falls on the north side of the highway generally does not flow in the
direction of the CTM site.
 As a result of field investigation by a standard penetration test (“SPT”) conducted at CTM

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

site, it was found that all boreholes feature a minimum of 4 consecutive SPT refusals (> 50
blows per 25 mm penetration), starting at depths ranging between 5 m and 15 m.
 Tropical storms hit Mozambique once a year on average and lesser-magnitude tropical
depressions hit the country three to four times per year.
 In February 2000, two tropical cyclones landed in Mozambique and devastated the economic
and social infrastructure across the country. The maximum total precipitation of 653 mm was
a record for this month and accounted for approximately 80% of Maputo’s normal annual
precipitation of 800 mm.
 On February 6, 2000, the turbine buildings in CTM site suffered from flood damage. This
damage was not caused by inundation from river water or storm surges, but was due to poor
drainage within the CTM.

6． Basic Design
The basic design of the power plant is as follows:
 The proposed project at the CTM site has the following features:
(i) Major specifications
- Rated generation capacity: 70 to 110 MW
- Thermal efficiency (LHV): More than 50%
- Capacity factor: More than 80% (for base power supply)
- Fuel: Natural gas from Pande gas field
(ii) Major equipment
 Combined Cycle Gas Turbine (“CCGT”) plant
- GT and generator: 2 sets
- ST and generator: 1 set
- Heat recovery steam generator: 2 sets
- Air cooled condenser: 1 set
- Auxiliary facilities such as 11 kV switch gear, step-up transformer, and fuel
gas supply facility, water supply tank, etc.
 Civil works such as foundation piling, buildings
 Other facilities for water treatment, wastewater treatment, and fire fighting
 The control and monitoring system that will realize all-automatic operation of the generator
facility will be configured as a DCS that takes technology and costs into consideration. The
DCS facility will make it possible to control and monitor the whole generator facility,
including control and monitoring of common facilities.

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

7． Natural Gas Supply Plan

The natural gas supply plan is as follows:
 EDM expects to receive not only 2.8 MGJ/ year for the Maputo site, but also 3.2 MGJ/ year
for the Beluluane site, totaling 6.0 MGJ/ year for the project.
 According to the gas supply contract with MGC the available gas volume will be 4.5 MGJ/
year by July 2016, and it will increase to 5.8 MGJ/ year after July 2016.
 The gas price with MGC is assumed to be 5.6 USD/ MGJ (0.4 USD/ MGJ for transportation)
for the Maputo site.

8． Project Implementation Plan

The project implementation plan is as follows:
 The project implementation schedule is estimated as below:
- Selection of consultant: 8 months from the conclusion of loan agreement
- Selection of EPC contractor: 15 months from the selection of consultant
- Construction: 30 months from the notice to proceed
 No problems were found with the site preparation and the unloading & transportation of
heavy equipment. However, the planning progress of a new trunk road construction adjacent
to the construction site should be closely monitored.
 Consultant and EPC contractor shall be selected according to the JICA guidelines.

9． Project Cost
Project cost is as follows:
 Project cost was estimated based on the proposed project implementation schedule, price
trends of combined cycle power facilities, construction prices in Mozambique, required
manpower for consulting services, required activities and materials for operation and
maintenance (“O&M”) and other results of studies related to project cost estimates, and the
results of the project cost estimate is summarized in the following table.
JICA Finance Portion Cost (Million USD)
Power plant construction and associated works (EPC cost) 124,171
LTSA, training and spare parts 18,403
Consulting services 14,344
Contingencies and interest during construction 26,387
Total of JICA Finance Portion 183,305
Non Eligible Portion (site preparation, administration cost and tax) 11,487
Total 194,791

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

10． Financial and Economic Analysis

The financial and economic analyses are abstracted as follows:
 The financial soundness of EDM is analyzed on the basis of their financial statements. As
for the debt service capacity, the quick ratio except for 2007 had basically surpassed 100%.
Accordingly, the debt service capacity for the short-term of EDM is not significantly
worrying. On the other hand, the ratios of return on assets and return on capital during the
period from 2006 to 2010 were negative or close to zero in value. Hence, it can be said that
the profitability of EMD is defective. The profitability is expected to improve through
reviews and an increase in electricity sales price or the reduction in operation cost in the
future.
 The FIRR of the Project is at 6.7%, which exceeds 6.47%, short-term national loan interest
rates of the cutoff rate. Therefore the Project is regarded as financially viable. The debt
service coverage ratio (DSCR), which shows the sovereign debt payment, is normally
required to be 1.3 to 1.5 at minimum. If the DSCR of the project is over 2.2, it will meet
this criterion. Hence, the Project is considered to be a sound investment.
 The EIRR of the Project is calculated at 17.1%. Since the EIRR exceeds the opportunity
cost of capital in Mozambique (10%), the Project is judged to be economically feasible.
Furthermore, through the implementation of the Project, direct and indirect job creation is
expected. This job creation can contribute to the expansion of the economic scale of
Mozambique and poverty reduction that the Government of Mozambique considers a top
priority issue to be solved.

11． Environmental and Social Considerations

Environmental and social considerations are abstracted as follows:

 The following baseline information was collected and analyzed:
- Outline of the project components
- Natural environment conditions in and around the Project site (meteorology, air quality,
noise level, water quality, etc.)
- Socio-economic conditions in and around the Project site (administration, demography,
education & hygiene, industries, etc.)
- Environmental laws/regulations/standards, systems and related authorities in
Mozambique
 Based on the above baseline information, scoping and evaluation for the environmental and
social impacts were conducted. The results are summarized as follows:
- During construction

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Although there would be some impacts on air quality, noise & vibration and wastes
arising from construction works, these impacts are minor and temporary, and can be
readily reduced to a permissible level by application of appropriate mitigation measures.
- During operation
Since the power plant shall be designed and built to meet applicable environmental
regulations and standards in Mozambique, there is no significant environmental issues
expected.
 Land acquisition and resettlement are not necessary for the Project because the proposed
site is within the vicinity of the existing power plant owned and operated by EDM, and
there are no resettlements involved in the Project because there are no legal and/or illegal
settlers that will be displaced.

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 Chapter 1

Introduction
 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Chapter 1 Introduction

1.1 Background of the study

The purpose of this “Preparatory Study on Gas-Fired Power Plant Development in
Mozambique” is to prepare an approximate design and Feasibility Study (FS) for the gas-fired
combined cycle power plant building project for which the Republic of Mozambique
(“Mozambique”) requests Japanese Official Development Assistance (“ODA”) and to make the
necessary investigations for the examination in order to execute it as a Japanese onerous fund
cooperation project.

The background of this study is as follows:

 In 2011, the nationwide power demand of Mozambique is only 616 MW of the maximum
generating capacity with 4,068 GWh/year of gross power production, however there has
been remarkable growth in the annual average increase rates in the past 5 years, i.e., 14.1%
in maximum generating capacity and 11.6% in gross power production. In particular,
maximum generating capacity only in Southern Mozambique is 369 MW which is 60% of
the 616 MW mentioned above with the annual average increase rate showing steady
growth.
 Although Electricidade de Mozambique (“EDM”) is making efforts to ensure power supply
capacity, e.g., rehabilitation of old small-scaled hydroelectric and thermal power plants,
purchase of electric power from independent power producers (“IPP”) power supply being
built in the Ressano Garcia area, and capital participation in IPP, the urgent issue to satisfy
mid- and long-term power demand is to ensure a new power supply for Maputo.
 Based on such background, the Mozambique government requested Japanese ODA from
the Japanese government in January, 2012, to support building a gas-fired combined cycle
power plant in Southern Mozambique (50 MW capacity).

1.2 Purpose of the study

The purpose of this study is to evaluate the approximate design and FS for the gas-fired
combined cycle power plant building project requested by the Mozambique government and to
make investigations necessary for the examination to execute it as Japanese ODA loan, i.e., the
necessity of this project, overview, project cost, implementation schedule, implementation
method (procurement and execution), business implementation system, operation and
maintenance management, environmental and social considerations.

1.3 Scope of works

Maputo and Matola in Mozambique (Figure 1.3-1)

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Mozambiqu

CTM Site

Maputo

Maputo

Matola city

Maputo city

Maputo

: Main rivers : Beluluane Industrial

: Main roads : Maputo Cargo Terminal
: Railway : Matola Bulk Terminal
:New gas pipeline route : CTM Maputo Site
: Existing gas pipeline route (MGC) : Beluluane Site

(Source: JICA Study Team)

Figure 1.3-1 Target area

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This study shall be organized and implemented based on the study items in Table 1.3-1
consistent with the Japan International Cooperation Agency’s (“JICA’s”) operational guidance.

Table 1.3-1 Study items

Stage-1 Basic Survey: Background and consistency with key national plans
4.1.1 Submission and discussion of Inception Report
(1) Analysis of relative documents and planning of surveys
(2) Draft of Inception Report
(3) Discussion of Inception Report with JICA and counterpart (“C/P”)
4.1.2 Review of background and consistency with key national plans
(1) Review of the power development master plan of Mozambique
Review of track records and plans of other international donors for the
(2)
power sector
(3) Review of social and economic status of Maputo and surrounding area
Review of power demand forecasts, operational records and development
(4)
plan of Mozambique’s power system
(5) Confirmation of comprehensive benefits from the Project
Stage-2 Selection of the project site
4.1.3 Selection of the project site
(1) Comparative study
(2) Draft and discussion of Progress Report for decision making
Stage-3 Feasibility study
4.2.1 Survey of relevant information for basic design
(1) Site conditions
(2) Socio-economic conditions
(3) Fuel gas supply plan
(4) Power transmission and power system stability
4.2.2 Planning of project outline
(1) Purpose of the Project
(2) General overview of Combined Cycle Power Plant (“CCPP”)
Terms of Reference (“TOR”) and scope of works for the consulting service
(3)
to the project
4.2.3 Basic design
(1) Plot plan
(2) Type of power plants and unit capacity
(3) Fuel gas supply plan
(4) Condenser cooling system
(5) Civil work
(6) Mechanical work
(7) Electrical work
(8) Common facility
(9) Substation and transmission facility
(10) Other auxiliary equipment
(11) Transportation route for major parts of equipment
4.2.4 Planning of procurement and construction
4.2.5 Project implementation plan
4.2.8 Socio-environmental consideration
(1) Legal regulation of socio-environmental consideration

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(2) Socio-environmental conditions of the Project site

(3) Scoping
(4) Baseline data correction
(5) Analysis of environmental impact
(6) Mitigation plan
(7) Monitoring plan
(8) Checklists of JICA Guidelines for Environmental and Social Considerations
(9) Stakeholders’ meetings
(10) Support to making Environmental Impact Assessment (“EIA”) report
4.2.9 Compensation plan for land acquisition and inhabitant resettlement
Stage-4 Project implementation plan
4.2.6 Organizational system at construction stage
(1) Establishment of Project Management Unit (“PMU”)
(2) Organizational structure and manpower allocation of PMU
(3) Finance and budget of PMU
(4) Technical capacity of PMU
(5) Experience of PMU for similar projects
Organizational system at the operation and maintenance stage
4.2.7 (organizational structure, manpower allocation, finance and budget,
technical capacity, and experience)
4.2.10 Project cost
4.2.11 Listing of points to consider for ODA projects
4.2.12 Monitoring index for project effectiveness
4.2.13 Draft and discussion of Draft Final Report
4.2.14 Organizing a workshop in Japan
4.2.15 Draft and submission of Final Report

(Source: JICA Study Team)

Figure 1.3-2 shows every component of the Study and the linking structure. The implementation
schedule of the Study is shown in Figure 1.3-2.

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Power Development Planning Study Technical and Socio-Environmental Study

Stage-1 Basic Survey Stage-1 Basic Survey

 Review of the power development master plan
 Power demand forecast and supply  Review of up-front surveys and data
balance collection
 Power system development plan
 Transmission loss, generation cost, tariff
 Review of track records and plans of other Stage-2 Comparative Study of Candidates
international donors
 Review of social and economic status of  Pros and cons analysis by criterion
Maputo and surrounding area  Land, transportation access
 Confirmation of comprehensive benefits from  Geography, geology, vegetation,
the Project meteorology, natural disasters
 Improvement of electrification rate and  Condenser cooling system, cooling
planned outage rate water, industrial water, fuel
 Improvement of living standards in  Power network constraints
Maputo area  Socio-environmental considerations
 Job creation  Over dimension cargo

1st Workshop in Maputo

 Attendance from C/P (Electricidade de Mozambique (“EDM”), Ministry of Energy (“ME”), etc.), JICA
mission, and JICA Study Team
 Selection of the project site

Stage-3 Feasibility Study

Stage-3 Feasibility Study  Site survey
 Setting development scale  Environmental and social considerations
 Power demand forecast survey
 Gas demand forecast  Topographic, geological and oceanographic
 Comparative study of plant type, surveys
power output, and unit capacity  Facility design
 Analysis of transmission capacity  Design of power block and auxiliary facility
 Estimation of Engineer Procure and
Construct (“EPC”) cost and other costs
 Procurement and transportation
 Draft report of basic design and
construction plan
 Socio-environmental considerations
 Collection and review of data required for
assessment of indicated/expected
environmental and social impacts
 Assessment of indicated/predicted
environmental and social impacts
 Stakeholder meeting and workshops

Stage-4 Project Implementation Plan

 Financial and economic analysis, and setting
up project monitoring index
 Listing of points to consider for ODA Stage-4 Project Implementation Plan
projects  Comprehensive evaluation of feasibility
 Project execution plan (project cost, finance plan,
project schedule)
 Organizational system at construction stage
 Organizational system at operations and
maintenance (“O&M”) stage

2nd Workshop in Maputo

 Attendance from C/P (EDM, MOE, etc.), JICA mission, and JICA Study Team
 Confirmation of feasibility and decision of project implementation plan

(Source: JICA Study Team)

Figure 1.3-2 Overall study flow

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Year 2012 Year 2013

September October November December Jan. Feb. Mar.
1st Survey in Mozambique 2nd Survey in MZ Workshop in Japan

Events 1st Survey in Japan 2nd Survey in Japan 3rd Survey in Japan
Stage-1 Basic Survey
 Review of the power development master plan Stage-3 Feasibility Study
1st Workshop in 2nd Workshop in
 Power demand forecast and supply balance  Setting development scale Workshop in
 Power system development plan Maputo  Power demand forecast Maputo
 Transmission loss, generation cost, tariff  Attendance Japan(around 1
 Gas demand forecast  Attendance from
 Review of track records and plans of other international donors
 Review of social and economic status of Maputo and surrounding area
from C/P  Comparative study of plant type, power output, and unit C/P (EDM, week)
 Confirmation of comprehensive benefits from the Project (EDM, capacity MOE, etc.), JICA
 Visits to CCPP,
 Improvement of electrification rate and planned outage rate MOE, etc.),  Analysis of transmission capacity mission, and
Power Development  Improvement of living standards in Maputo area turbine factory,
JICA JICA Study
 Job creation Stage-4 Project Implementation Plan etc.
Planning Study mission, and  Financial and economic analysis, and setting up project monitoring Team
JICA Study index  Confirmation of
Team  Listing of points to consider for ODA projects
feasibility and
 Selection of Stage-3 Feasibility Study decision of
the project  Site survey project
Stage-1Basic Survey
 Review of up-front surveys and data collection site  Environmental and social considerations survey implementation
 Topographic, geological, and oceanographic surveys plan
 Facility design
 Design of power block and auxiliary facility
Stage-2 Comparative Study of Candidates  Estimation of EPC cost and other costs
 Pros and cons analysis by criterion  Procurement and transportation
 Draft report of basic design and construction plan
 Land, transportation access
 Socio-environmental consideration
 Geography, geology, vegetation, meteorology, natural disasters
 Collection and review of data required for assessment of
 Condenser cooling system, cooling water, industrial water, fuel
indicated/predicted environmental and social impacts
 Power network constraints  Assessment of indicated/predicted environmental and social
 Socio-environmental considerations impacts
 Over dimension cargo  Stakeholder meeting and workshops
Technical and  Assistance for making compensation plans
Socio-Environmental
Study

Stage-4. Project implementation plan

 Comprehensive evaluation of feasibility
 Project execution plan (project cost, finance plan, project
schedule)
 Organizational system at construction stage
 Organizational system at O&M stage

Contract negotiations Oceanographic survey

with local consultants

Geographic and geological survey
Surveys by Local
Consultants Socio-environmental survey

Inception Progress Report Draft Final Final Report

Reporting
Report Report

(Source: JICA Study Team)

Figure 1.3-3 Study schedule

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1.4 Organizational framework for the Study

The team for the Survey is a joint venture of consultants consisting of Tokyo Electric Power
Service Co., Ltd (“TEPSCO”) and Oriental Consultants Co., Ltd. (“OC”), who have been
entrusted with the consulting services for the Survey by JICA. The composition and designation
of the JICA Study Team is shown in Figure 1.4-1.

Hideki YUKIMURA(Team Leader/ Power Generation Planning）

Power Development Planning Study Technical and Socio-environmental study

Nobuyuki KINOSHITA Toshihiko WATANABE(Thermal Power

(TL and SS Planning) Plant)

Hideyuki OKANO
(Fuel Planning)
Masaho AOKI
(Electric & IC)
Teruhiko TSUMURA
(Chief Economical & Financial Analysis) Exchange
Information,
Discussion Toshiyuki KOBAYASHI
Takahiro MOJI (Cooling system)
(Assistant Economical & Financial
Analysis)

Mitsuru MIYASHITA
Discussion
Info.
Exchange

(Power Civil)

Exchange
Environmental and Social Consideration
Information, Kazutora KONO

Gloria E. SATO Discussion (Construction/Procurement Plan Project

(Environmental & Social Consideration) Cost) Estimation）

(Source: JICA Study Team)

Figure 1.4-1 JICA Study Team

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When the need arises for smooth operation of the Survey in any part thereof, MOE and/or EDM
are kindly requested to assign counterpart personnel, who will work closely with the members
of the JICA Study Team, on a full time or a part time basis depending on the requirements, to
the greatest extent as is practically possible. The expected roles of the counterpart personnel are,
for instance, as follows:

 To make appointments and to set up meetings with authorities, departments and other
organizations and firms the JICA Study Team intends to visit for the purpose of this
Survey.
 To attend field surveys and other locations with the JICA Study Team and to provide any
assistance in relation to accommodation, work rooms, adequate transportation, obtaining
permissions if required, etc.
 To assist and to advise the JICA Study Team as much as possible on their collection of data
and information.

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 Chapter 2

Overview of Power Sector

 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Chapter 2 Overview of Power Sector

2.1 Social and Economic Conditions

2.1.1 Land Area and Population

Mozambique has a total land area of 799,380 km2 politically divided into 10 provinces and 1
city namely, Niassa, Cabo Delgado, Nampula, Zambezia, Tete, Manica, Sofala, Inhambane,
Gaza, Maputo province and Maputo city. It has a total population of 23 million according to the
latest statistics from the National Statistics Institute (see Table 2.1-1). There are more than 70
percent of this population are living in rural areas concentrating along the coast (more than
50%), mostly young (45.9% is less than 15 years old).

Table 2.1-1 Total Population, Area and Population Density by Province, 2011

Percent
Provinces Population Area km2 Inhab/km2
Struct.
Total 23,049,621 100 799,380 29
Niassa 1,415,157 6 129,056 11
Cabo Delgado 1,764,194 7.6 82,625 21
Nampula 4,529,803 19.2 81,606 56
Zambezia 4,327,163 18.7 105,008 41
Tete 2,137,700 9.2 100,724 21
Manica 1,672,038 7.3 61,661 27
Sofala 1,857,611 8 68,018 27
Inhambane 1,402,245 6.5 68,615 20
Gaza 1,320,970 6.1 75,709 17
Maputo Province 1,444,624 6.3 26,058 55
Maputo City 1,178,116 5.1 300 3,927

(Source: Statistical Yearbook 2011 of National Institute of Statistics)

2.1.2 Poverty Incidence

Mozambique has continued the fastest growing non-oil economy in Sub-Sharan Africa with an
average growth of 7.5% per year (1993-2009). Despite this progress, the country lacks
economic diversification, weak institutions, lacks infrastructure development, among others that
hinders the country to move forward. According to the Report from the Ministry of Planning
and Development, there was a decrease in poverty incidence from around 70 percent in 1996 to
around 55 percent in 2003 as shown in Fig. 2.1-1. In 2008/09, the poverty condition has
stagnated at around 55 percent due to the slow growth of agricultural productivity, recurrent

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weather shocks that reduced the yields, decline trade due to increase in international food and
fuel, among others.

(Source: Ministry of Planning and Development, 2010)

Figure 2.1-1 Poverty Headcount (%)

In recent years, the country has undertaken a series of economic reforms. Almost all aspects of
the economy have been liberalized to some extent. Mozambique has considerable mineral
resources although exploitation has been limited by its recently ended civil war. But the large
reserves of natural gas in the Pande and Temane of Inhambane province have exploited, which
is set to become a major source of foreign exchange.
Agriculture is the most important sector and is mostly carried out by peasant farmers who
cultivate 92% of the total cropland. Commercial farming occupies only 250,000 hectares, or 8%
of the total land cultivated. Though the contribution of agriculture to the Gross Domestic
Product (GDP) is between 25% and 30%, an estimated 80% of the country's population gains its
livelihood from this sector emphasizing the importance of agriculture to the nation. Most of the
agricultural activities rely on rain that falls from November to December and are limited to one
season.

2.1.3 Mozambique’s Rich Resource

Mozambique is one of the largest power producers in the SADC region. Hydropower is
Mozambique’s most important commercial energy resource, with the potential estimated at
about 14,000 MW, of which about 2,300 MW has so far been developed, 2,075 MW at Cahora
Bassa Dam located at the Zambezi River and the remaining is distributed among a number of
sites throughout the country. The capacity at Cahora Bassa is committed to the supply electricity
to Mozambique, Zimbabwe, and Malawi. However, the majority of the power generated by

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Cahora Bassa is sent to the Apollo substation in South Africa and is then sent to the Southern
African Power Pool.
Apart from hydro resources, Mozambique has not yet to exploit its oil reserves. Presently,
accumulation of natural gas deposits have been discovered on-shore in the provinces of the
aforesaid Inhambane and Cabo Delgado. According to statistical estimate, the total natural gas
reserves in Mozambique are 4.8 to 8.8 TCF in the Mozambique Basin and 52.5 to 110 TCF in
the Rovuma Basin. The majority of production of gas is now being exported to South Africa
through a pipeline.
Moreover, Mozambique has three relatively large known deposits of coal located in the
Province of Tete. Total coal reserves are estimated at about three billion tonnes. Coal has been
produced since 1940, from Moatize mines, both for in country use and export. Although the
operations had to be suspended due to civil war, it restarted the activities.

2.1.4 Economic Condition

(1) Macroeconomic
The Gross Domestic Production (GDP) per capita of the country was estimated at around USD
635 in 2012 and had steadily increased during the period of 2005 to 2012 (refer to Table 2.1-2).
The GDP between 2005 and 2012 had also increased. Fiscal performance remained strong until
2012, with government revenue rising from 20.12% of GDP in 2005 to 28.74% of GDP in 2012.
Government Gross Debt had decreased from 131.87% of GDP in 2000 to 39.98% in 2012.
Receipts of Official Development Assistance (ODA), which has increased year by year,
amounted to USD 2,013 million in 2009 and ODA will be continuously carried out, while the
amount of the Foreign Direct Investment (FDI) recorded at USD 881 million in the same year.
The detailed condition of FDI will be described afterward.

Table 2.1-2 Selected Macroeconomic Indicators

Indicators Unit 2000 2005 2006 2007 2008 2009 2010 2011 2012
National Accounts
GDP at Current Prices Billion US $ 4.138 6.579 7.215 8.121 9.943 9.967 9.481 12.830 14.27 (f)
GDP per Capit at Current Prices US$ 236.46 336.49 361.80 399.26 479.23 471.00 439.25 582.61 (f) 635.44 (f)
Real GDP Growth Rate % 14.7 8.4 8.7 7.3 6.8 6.4 8.1 … …
Government Finance
Government Revenue % GDP 21.93 20.12 22.93 25.2 25.34 27.06 29.68 29.44 (f) 28.74 (f)
Total Expenditure and Net Lending % GDP 23.66 22.90 26.99 28.15 27.81 32.57 33.64 34.38 (f) 35.06 (f)
Overall Deficit (-) / Surplus (+) % GDP -5.3 -3.5 -0.5 -2.4 -2.7 -5.1 -5.4 … …
External Sector
Exports Volume Growth (Goods) % 19.95 16.78 10.45 -3.499 8.713 -1.195 -9.380 4.278 (f) 1.459 (f)
Imports Volume Growth (Goods) % -13.68 -0.0990 5.561 1.495 19.67 13.90 -2.061 22.83 (f) 9.504 (f)
Current Account Balance Billion US $ -0.697 -0.7610 -0.7730 -0.7850 -1.179 -1.220 -1.113 -1.667 (f) -1.818 (f)
Current Account Balance % GDP -16.66 -11.56 -10.72 -9.670 -11.86 -12.24 -11.74 -12.99 (f) -12.74 (f)
Debt and Financial Flows
Government Gross Debt % GDP 131.87 80.96 53.61 41.92 42.14 40.13 39.51 33.20 (f) 39.98 (f)
Net Official Development Assistance Million US $ 906.2 1,297.00 1,605.70 1,778.10 1,996.10 2,013.30 … … …
Net Foreign Direct Investment Million US $ 139.2 107.9 153.7 427.4 591.6 881.2 … … …

(Source: ADB Statistics Department; IMF: World Economic Outlook, October 2010 and International Financial Statistics, April
2011; ADB Statistics Department: Development Data Platform Database, April 2011. United Nations: OECD, Reporting),
Notes… Data Not Available; (f) Forecast
As the GDP by sector is shown in Table 2.1-3, the agriculture, livestock, hunting and forestry

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sector has a 24% share of GDP and is the largest sector in the country, followed by
manufacturing sector, transport, storage and communication sector, trade sector, real estate
activities, rentals and services sector, financial activities sector, water and electricity sector and
education sector, public administration, defense and social security sector and construction
sector and so forth. Those shares have hardly changed for the last ten years. The proportion of
the sector of electricity, gas and water had been almost stable 4.4% to 4.8% during the period of
2001 to 2010 in the above table.

Table 2.1-3 Share of Gross Domestic Product by Sector (2001 to 2011)

Unit:%
No. Description 2001 2002 2003 2004 2005 2,006 2007 2008 2009 2010 2011
1 Agriculture, livestock, hunting and forestry 23.1 23.7 23.4 22.8 22.5 22.9 23.1 23.6 23.8 23.6 23.7
2 Fishing, aquaculture, and related services activities 2.0 1.9 1.9 1.8 1.7 1.6 1.7 1.7 1.4 1.4 1.4
3 Extrative industries 0.5 0.5 0.6 0.9 0.9 1.0 1.1 1.1 1.1 1.2 1.3
4 Manufacturing 13.7 13.6 15.0 15.7 14.8 14.0 13.5 13.2 12.7 12.4 12.3
5 Water and electricity 4.4 4.4 4.6 4.9 5.3 5.5 5.6 4.6 4.9 4.8 4.8
6 Construction 3.3 3.3 3.4 3.0 3.1 3.2 3.3 3.5 3.4 3.4 3.3
7 Trade 9.9 9.5 9.5 9.5 9.8 11.0 11.2 11.2 11.2 10.8 10.2
8 Vehicle repairs, motocycles and good 0.5 0.4 0.4 0.4 0.4 0.4 0.3 0.3 0.3 0.4 0.4
9 Acomodation, restaurants and similar 1.5 1.5 1.5 1.4 1.5 1.5 1.6 1.7 1.6 1.6 1.6
10 Transport, storage and comunication 9.8 9.7 9.4 9.5 9.5 9.7 9.9 10.4 10.8 11.6 12.0
11 Financial activities 3.0 3.2 3.3 3.9 5.3 5.1 5.2 5.0 5.2 5.4 5.4
12 Real estate activities, Rentals and services 10.9 10.1 9.6 9.4 8.8 8.1 7.6 7.2 6.9 6.5 6.2
13 Public administration, defense and social security 3.9 3.8 3.7 3.6 3.6 3.6 3.6 3.6 3.6 3.7 3.7
14 Education 3.4 3.2 3.3 3.4 3.5 3.5 3.7 3.7 3.9 4.0 4.0
15 Health and social action 1.2 1.2 1.2 1.2 1.2 1.2 1.3 1.4 1.4 1.4 1.4
16 Other collective services activities 2.4 2.2 2.1 2.0 1.9 1.8 1.7 1.7 1.6 1.5 1.5
17 SIFIM -1.5 -1.7 -2.6 -2.8 -2.7 -3.2 -3.1 -3.0 -3.1 -3.2 -3.1
18 Tax on products 8.0 9.2 9.6 9.3 8.9 8.9 8.7 9.2 9.3 9.4 10.0
Gross Domestic Product 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0

(Source: Central Bank of Mozambique)

(2) Foreign direct investment (FDI)

It can be said that Mozambique’s economy has been driven by foreign direct investment (FDI).
Private sector investment was over USD 1.9 billion in 2011 as a result of large FDI in coal
mega-projects. A total of 30,000 new jobs were created by the 285 new projects, of which 13
were in the Nacala Exclusive Economic Zone, representing a USD 400 million investment from
export companies.
The Maputo area has traditionally had an overwhelming concentration of growth and jobs but
this has started to change. In 1990–2003, 75 percent of FDI in Mozambique was concentrated in
Maputo City and Maputo Province. Its share of new investments has steadily declined, from
nearly 75 percent in 2006 to less than 20 percent in 2009. This shows a more even distribution
of new investments to other regions of the country, especially in the mineral resources, energy,
agriculture processing, and more recently, tourism and construction sectors.
The data of Centro de Promocao de Investimentos (CPI) for authorized investments by sector
from 2005 to 2009 shows that Maputo Province has a fairly well-diversified economic base,
with investments in transport, telecommunications, the financial sector, industry, and tourism
(Refer to Table 2.1-4).

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Table 2.1-4 CPI-Authorized Investments in Maputo Province by Sector, 2005-2009

2005 2006 2007 2008 2009 2005-2009 2005 - 2009 Mozambique Total

No. of Committed No. of Committed No. of Committed No. of Committed No. of Committed No. of Committed No. of Committed
Sector Employ investment Employ investment Employ investment Employ investment Employ investment Employme investment Employm investment
ment (MZN) ment (MZN) ment (MZN) ment (MZN) ment (MZN) nt (MZN) ent (MZN)
Transport &
209 5,852,549 1,388 158,026,142.00 515 57,681,514 356 83,813,954 365 17,794,625 2,833 323,168,785 4,134 439,361,325
communication
Agriculture and
25 10,500,000 147 3,203,875 172 13,703,875 816 53,397,122
fishiries
Agriculture and
3,511 112,771,297 1,232 23,073,927 2,401 57,314,514 1,698 31,147,316 1,100 37,834,066 9,942 262,141,121 49,545 6,303,139,512
fishiries
Construction 50 1,150,000 83 1,983,036 933 7,529,977 298 13,426,833 206 3,975,800 1,570 28,065,646 4,375 149,649,500
Industrial 708 28,592,271 959 21,777,570 5,079 325,242,053 2,065 137,485,597 858 21,291,616 9,669 534,389,108 18,705 892,668,673
Mineral
resources and 154 15,638,650.00 292 23,000,000 446 38,638,650 1,903 6,627,891,567
energy
Services 1,445 43,877,978 1,445 43,877,978 3,545 167,730,328
Tourism &
2228 47,511,506 1,709 368,823,696 605 28,044,286 1,615 68,165,022 73 8,002,172 6,230 520,546,682 17,139 1,310,411,321
hotels
Banking,
insurance, and 84 1,900,000 62 2,933,500 20 1,532,857 29 12,833,333 195 19,199,690 394 39,883,750
leasing
Others 540 14,545,747 6,378 48,766,443 314 51,957,706 562 32,382,301 7,794 147,652,197 8,651 239,389,817
TOTAL 7,484 227,962,021 12,103 648,384,314 9,892 539,802,908 6,623 379,254,357 4,194 135,980,132 40,296 1,931,383,732 109,207 16,223,522,916

(Source: Mozambican Authorities (CPI 2005-2009))

Table 2.1-5 CPI-Authorized Investments in Maputo Province by District, 2005-2009

2005 2006 2007 2008 2009 2005-2009

No. of Committed No. of Committed No. of Committed No. of Committed No. of Committed No. of Committed
District Employ investment Employ investment Employ investment Employ investment Employ investment Employme investment
ment (MZN) ment (MZN) ment (MZN) ment (MZN) ment (MZN) nt (MZN)
City of Maputo 1,322 46,336,999 9,910 558,554,512 2,438 140,704,758 1,022 129,724,692 14,692 875,320,961
Matola 301 9,978,178 844 29,333,173 3,692 52,720,855 2,470 90,051,628 1,361 64,810,142 8,668 246,893,976
Boane 323 14,894,037 25 5,435,000 718 174,885,695 398 41,167,965 158 4,503,000 1,622 240,885,697
Inhaca 15 320,800 15 320,800
Machava 18 187,217 1,152 14,050,606 1,170 14,237,823
Magude 25 2,857,143 10 160,000 35 3,017,143
Manhiça 10 325,000 514 4,280,000 265 9,001,200 460 2,570,100 1,249 16,176,300
Marracuene 5,000 50,000,000 30 450,000 660 114,714,286 366 4,915,652 214 6,549,119 6,270 176,629,057
Matutuine 335 3,883,447 149 44,609,432 1,738 51,655,714 805 82,301,903 687 41,534,199 3,714 223,984,696
Moamba 150 99,500,000 534 4,297,680 1,141 18,969,300 112 1,462,966 1,937 124,229,946
Namaacha 601 5,544,517 117 520,800 61 1,732,731 50 500,000 829 8,298,048
Xinavane 95 1,389,285 95 1,389,285
TOTAL 7,484 227,962,021 12,103 648,384,314 9,892 539,802,908 6,623 379,254,357 4,194 135,980,132 40,296 1,931,383,732
Total
15,113 482,186,373 19,372 850,209,001 27,469 8,062,268,793 20,495 1,080,254,032 26,758 5,748,620,716 109,207 16,223,538,916.00
Mozambique

(Source: Mozambican Authorities (CPI 2005-2009))

Still, Maputo province remains the predominant business and financial center of the country,
and within the province, the bulk of new investments continue to take place in Maputo City,
with Matola District being a distant second (refer to Table 2.1-5). FDI has given rise to
employment promotion, capital such as machinery and infrastructure, creation of added value
products, and economic development.

(3) Industry in Maputo Area

The country‘s largest industrial park, Beluluane, and the Mozal aluminum smelter are both

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located in Maputo, as are other large beer, soft drink, cement, and cereal milling industries (e.g.,
Cimentos de Mozambique, Cervejas de Moçambique, Coca-Cola). There are also a number of
large and promising agribusiness investments such as the Maragara sugar mill and Bananalandia,
which supplies bananas to both the domestic and South Africa markets. The province also
benefits from a number of universities and technical schools. Further, much of the country‘s
tourism growth has taken place in the Maputo area, which includes the Maputo Elephant
Reserve and the Kruger Transfrontier Park, which Mozambique shares with South Africa and
Swaziland.
As for the Mozal aluminum smelter, since 1998, Mozambique has been engaged in an intensive
effort to attract megaprojects in order to establish itself as a favorable environment for FDI. The
US$2.8 billion aluminum smelter projects Mozal I and II, which had been constructed in the
Matola district in the late 1990s and in the early 2000s, are the largest aluminum smelter
projects in this country. Non mega-projects FDI rose in importance during the period of 2006 to
2010 and the inflows have become increasingly diversified, which accounted for close to 44
percent of total FDI inflows.
The smelters produce about 506, 000 tons of aluminum ingots per year. Alumina is sourced in
Australia and aluminum ingots are exported mainly to the EU. The firm is a joint venture of the
Australian-British BHP Billiton mining company (47%), the Japanese Mitsubishi Corporation
(25%), the Industrial Development Corporation of South Africa (24%), and the Government of
Mozambique (4%).
With regards to Beluluane Industrial Park, as noted above, Maputo Province hosts Beluluane
Industrial Park, located in the Matola Industrial Zone. The World Bank‘s Private Sector
Development Project financed establishment of the park in 2007. The park spans 24 hectares
and has attracted 22 businesses employing some 1,000 workers and has generated US$20
million in investment. The park is located across from Mozal.

(4) The Industrial Customers for the Power Demand in Maputo Area
In and around Maputo area there are substantial business enterprises that demand the new power
in order to operate their business. Such enterprises require new electricity of 527MW as a whole
by 2015/16 (Table 2.1-6). There is a growing likely that the economic situation in Maputo area
is and will be quite active due to being the increasing energy demand for the industrial
customers in Maputo.

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Table 2.1-6 Current and Future Industrial Customers for Power Demand in
Maputo

INITIAL LOAD
No. CUSTOMER NAME LOCATION STATUS
(MW)
1 Incomati Sugar Xinavane/Maputo 15 Operational
2 Maragra Sugar Manhiça/Maputo 10 Operational
3 Steel Tube Factory Beluluane/Maputo 10 Operational
4 Exports to SEC Swaziland 100 Operational
5 Exports to LEC Lesotho 20 Operational
6 CIF MOZ Salamanga 20 Construction
7 Facim-Sogex Multipurpose Maputo 15 Construction
8 Intaka 5000 Houses Maputo 20 Construction
Catembe Bridge + Residential
9 Maputo 30 Construction to start 2013
Expansion Zone
10 GS Cimentos Beluluane/Maputo 20 Committed 2014
11 Cim Magude/Africa Great Wall Magude/Maputo 22 Committed 2014
12 New Sommershield Maputo 15 Committed 2014
13 Matola Mall Matola Maputo 15 Committed 2014
14 ADIL Cimentos Maputo 10 Potential 2014
15 Techobanine Port Salamanga/Maputo 18 Potential 2015-16
16 FerroxChang Belluluane/Maputo 7 Potential 2015-16
17 Cim Moç-Matola/CIMPOR Matola/Maputo 15 Operational/Expansion
18 Matola Coal Terminal – Fase IV Matola/Maputo 10 Expansion
19 Chibuto Heavy Sands Chibuto/Gaza 45 Potential
20 Chibuto Heavy Sands Smelting Chibuto/Gaza 88 Potential
21 Arcellor Mittal Beluluane/Maputo 22 Potential
TOTAL 527
(Source: EDM)

2.2 Overview of Network System

2.2.1 Network System

Figure 2.2-1 is a diagram of the network system in Mozambique. Since Mozambique has a large
geographical area extending 2,000 km from north to south, the network system is separated into
two systems: one for the southern area and the other for the central and northern areas. These
systems are independently operated, without being linked to each other.

The Cahora Bassa Hydroelectric Power Plant (“HCB”) with an output of 2,075 MW, the major
power source in Mozambique, is linked to the network for the central and northern areas. A part
of the generated power is transmitted to the central and northern areas by means of a 220 kV AC
transmission line and the power supplied meets the load of these areas. Power is also sent to a
neighboring country, Zimbabwe, by means of a 400 kV AC transmission line. However, the
majority of the power generated by HCB is sent to the Apollo substation in South Africa by a

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535 kV DC transmission line and is then sent to the Southern African Power Pool (“SAPP”).

Since the system for the southern area, which covers Maputo, the capital of Mozambique, is
located over 1,000 km from HCB, power is imported from SAPP via the networks of South
Africa and Swaziland by means of a 400 kV AC transmission line. As a result, more than 80%
of domestic demand is supplied by re-imported power.

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(Source: Characterization of the transmission network 2010 (EDM))

Figure 2.2-1 Network System Diagram

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2.2.2 Southern System

Since the southern gas-fired thermal power plant will be situated in Maputo City and its vicinity,
it will be connected to the southern system. Figure 2.2-2 shows the southern system and
transmitting capacity of the transmission lines.

Power is currently transmitted from the power pool of South Africa to Mozambique via a 400
kV transmission line stepped down from 400 kV to 275 kV and 132 kV at the Maputo
substation. Power is transmitted to the Mozal aluminum refinery plant, the biggest user of
Mozambique located in the neighborhood of the Maputo substation and accounting for about
70% of the total power demand of the southern system, via three dedicated transmission lines of
132 kV (275 kV designed).

Power to general consumers is further stepped down to 110 kV or 66 kV at the Infulene and
Matola substations. The 110 kV voltage is used only in the northern region of the southern
system, while the 66 kV system plays a role of power transmission in the other regions. The
transmitting capacity of the 66 kV transmission lines is relatively small, standing at 36 MW to
57 MW (with the power factor assumed to be 95%). There are concerns that overloading may
occur in the near feature as demands grow.

Turning attention to the two candidate sites for the southern gas-fired thermal power plant, the
Beluluane site is located close to the existing Beluluane substation which is connected with the
main system through T-shape branching from the 66 kV Matola Gare-Boane line with a
transmission capacity of 36 MW. On the other hand, the CTM site is situated adjacent to the
existing CTM substation and is connected to eight 66 kV lines with a transmission capacity of
36 to 57 MW.

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Legend Lindela
64
400kV
Chongoene
275kV Lionde
132kV 94 64
94
110kV Corumana Xinavane 94
66kV Xai-Xai
South Africa Macia
Power station
94 94 Riopele
Substation Matola 455 Manhica
Gare 36
36 Laulane
Unit : MW 36
36
36 Infulene 36
South Africa 36
455 36 47 36 72
Maputo Machava SE6 SE8
455 62
1631
SE4
660 36
660 36
47 36
660 36
47
1631 Mozal 36 36 36 47
36 Matola 57 83 SE5
57 SE7
47
47 47
47
Swaziland Beluluane 47
CTM 47
47
Matola P.Mozal
47 47
36 Rio SE2
SE1
Cimentos SE3

Boane 47

Salamanga

(Source: Created with reference to PSSE network analysis data provided by EDM) (Unit: MW)

Figure 2.2-2 The Southern System and Transmitting Capacity of Transmission

Lines

2.2.3 Facilities in the Southern System

Table 2.2-1 shows the details of the transmission facilities in the southern system. The 400 kV
transmission lines are employed as international interconnection lines to South Africa and
Swaziland. The 110 kV transmission lines are used as supply lines from the base substations of
the system. Furthermore, the 66 kV transmission lines are utilized as local supply lines to meet
local demand.

Table 2.2-2 shows the details of the substation facilities. A 400 kV transformer is employed in
the Maputo substation to transform the receiving voltage from international interconnection
lines into 275 kV or 132 kV for domestic use. There are 275 kV transformers located at the
Infulene and Matola substations that are the supply bases of the southern system, and these
transformers are used for connection with the 110 kV or 66 kV system, aiming at local supply.
In addition, there are transformers with a primary voltage of 110 kV or 66 kV located at
substations for distribution to serve general loads.

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Table 2.2-1 Details of Transmission Facilities in the Southern System

Voltage Length Completion Capacity
From To
(kV) (km) Year (MVA)
Arnout Maputo 400 49.9 2000 1293
Edwalene Maputo 400 58.1 2000 1293
SE Matola Infulene 275 16 2000 479
Komatipoort Infulene 275 85 1972 479
SE Maputo Matola 275 16 2004 479
Motraco (Maputo) Mozal 275 (132) 3.5 2000 1293
Motraco (Maputo) Mozal 275 (132) 3.5 2000 1293
Motraco (Maputo) Mozal 275 (132) 3.5 2000 1293
Infulene Macia 110 125.0 1983 99
Macia Chicumbane 110 49.0 1983 99
Macia Lionde 110 53.0 1983 99
Infulene Corumana 110 92.0 1984 99
Komatipoort Corumana 110 40.0 1990 99
Chicumbane Lindela 110 233.8 2002 68
Infulene Boane 66 30.0 1982 38
Infulene 2M 66 4.5 2003 50
Infulene CTM 66 7.5 2004 38
Infulene CTM 66 7.5 2004 38
1975,1988,
Infulene Manhica 66 62.0 38
2004
Infulene Machava 66 7.5 1991 38
Infulene SE5(Compone) 66 15.1 1990 38
CTM Matola 66 4.9 1998 60
CTM SE6 66 3.8 1992 38
CTM Matola 66 4.9 1998 60
CTM Matola 66 4.9 1998 60
Matola Machava 66 2.5 1998 50
Matola Boane 66 21.9 1998 50
Matola Cimentos 66 2.7 1998 50
SE6 SE4 66 2.4 1998 38
SE4 SE5 66 4.8 1996 38
CTM SE3 66 5.4 2001 50
CTM SE2/3 66 5.4 2001 50
Boane Salamanga 66 76.7 2002 50
2M SE7 66 7.9 2004 50
2M SE7 66 7.9 2004 50
SE7 SE5 66 4.0 2004 88
SE3 SE1 66 2.1 2004 55
SE3 SE7 66 2.2 2005 77
Infulene CTM 66 7.5 1972 38
(Source: Characterization of the transmission network 2010 (EDM))

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Table 2.2-2 Details of Substation Facilities in the Southern System

kV Total
Name Year Voltage
400 330 275 220 132 110 66 Capacity
Beluluane 1998 66/11 - - - - - - 1 20
Boane 1980 66/33 - - - - - - 3 30
Central Termica 1972 66/33 - - - - - - 14 60
Infulene 1972 275/110/66 - - 6 - - 5 7 372
Lindela 2002 110/33 - - - - - 1 - 10
Lionde 1985 110/33 - - - - - 5 - 16
Machava 2004 66/33 - - - - - - 3 30
Macia 2002 110/33 - - - - - 4 - 10
Manhica 2000 66/33 - - - - - - 1 30
Manica 1972 110/33 - - - - - 1 6.3
Maputo (Matraco) 2000 400/275/132 3 - 1 - 3 - - 1500
Maputo (EDM) 2000 400/275 1 - 1 - - - - 400
Matola 275 2006 275/66 - - 1 - - - 7 320
Matola Rio 2003 66/33 - - - - - - 1 10
Matola Gare 2004 66/33 - - - - - - 3 30
Salamanga 2002 66/33 - - - - - 1 10
SE Movel 0
1997 110/33/22 1 10
(Xinavane)
SE Movel 2 2004 110/33 - - - - 1 - 10
SE Movel 3 (SE5) 2004 66/33 - - - - - 1 20
SE1 2003 66/11 - - - - - 1 30
SE2 2003 66/11 - - - - - 1 30
SE3 2001 66/11 - - - - - 4 60
SE4 1994 66/11 - - - - - 1 30
SE5 1990 66/11 - - - - - 5 20
SE6 1994 66/33/11 - - - - - 1 20
SE7 2004 66/11 - - - - - 4 30
SE8 2005 66/11 - - - - - 2 30
SE9 2005 66/11 - - - - - 2 60
(Source: Characterization of the transmission network 2010 (EDM))

2.2.4 Power Flow

The power flow has been analyzed using the 2011 network data provided by EDM. The analysis
results are shown in Figure 2.2-3. The maximum power flow by voltage class is provided in
Table 2.2-3. The maximum power flow of the 400 kV transmission line is 885 MW on the
Maputo-Amot line of the interconnection line with South Africa. This allows a sufficient margin
to meet the transmitting capacity of 1,631 MW. Similarly, both the 132 kV and 110 kV
transmission lines have a wide margin of transmitting capacity and have not lead to any
problems such as power overloads. In the 66 kV transmission lines, on the other hand, the
utilization rate of the facilities tends to be higher on the transmission lines where the power
transmitting capacity is as small as 36 MW (power factor assumed at 0.95). Above all, the

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power flow of the transmission line branching off at the Infulene-CTM line and leading to the
SE6 substation is 38 MW, which is slightly higher than the transmitting capacity. However,
power flow exceeding the capacity is found only in this transmission line.
Lindela 12

13
Chongoene 11
Lionde 7
7
30 25
5
Corumana Xinavane 46 9

Komatiport Xai-Xai
South Africa +3 11 Macia
3
61 Riopele
Matola 3 Manhica
61 11 8
Gare Laulane
18 43 8
21
161 13
3
Amot Infulene 32
4
South Africa 144 23
24 15
Maputo 336
Machava 26
33 SE6 SE8
4
885 15 16
337 851 SE4
851 38 16
30 24 2
850 8
17
5
302 Mozal 20
191 105 17 22
Matola 6 6 10 SE5
5 SE7
48
Edwaleni Beluluane 41
14 30
3
4
Swaziland 4
CTM
16 33
10 14
2 24
Matola P.Mozal 29
19 29
Rio 10 SE2 23
SE1
Cimentos SE3

Boane 14 8

8 Salamanga

(Source: Analysis results using PSSE network data provided by EDM)

Figure 2.2-3 Power Flow in 2011 (Unit: MW)

Table 2.2-3 Maximum Power Flow by Voltage Class

Voltage A. Power Flow B. Capacity Utilization Rate

Line Section
(kV) (MW) (MW) (%) (= A/B)
400 Maputo-Amot 885 1631 54
275 Maputo-Matola 336 455 74
132 Maputo-Mozal 284 660 43
110 Infulene-Xinavane 61 94 65
66 Branching point-SE6 38 36 106
(Source: Analysis results using PSSE network data provided by EDM)

2.2.5 Fault Current

Fault current analysis has been done using the 2011 network data provided by EDM. The results
of the analysis are provided in Figure 2.2-4 and the maximum fault current by voltage class is
illustrated in Table 2.2-4.

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The power system of the country is small-scaled and the southern system does not have a main
power supply. For these reasons, the fault current is as small as about 10 kA for each voltage
class, except on the Mozal 132 kV bus. Mozal is located close to the 400 kV Maputo substation
and is connected with three separate transmission lines. For this reason, Mozal is expected to
produce a fault current as large as 19.3 kA when faults occur.

Lindela 0.3

Chongoene 0.5
Lionde 0.7

0.7
Corumana Xinavane 0.9
Komatiport Xai-Xai
South Africa 1.0 0.9 Macia
Riopele
Matola 2.1 Manhica
Gare 1.1
4.1 5.5 Laulane
2.7
12.8, 5.8 8.4

Amot Infulene
South Africa
Maputo Machava 10.0 SE6 SE8
9.8 9.8 6.6
SE4
6.5
18.6 8.7
19.3

Mozal 5.9 9.2

10.0
Matola 10.8, 11.7 SE5
4.0 SE7
11.7
Edwaleni Beluluane
Swaziland 8.7
CTM
5.4
8.9
Matola P.Mozal
8.4
Rio 8.0 SE2 8.9
SE1
Cimentos SE3

Boane 4.2

0.9 Salamanga

(Source: Analysis results using PSSE network data provided by EDM)

Figure 2.2-4 Fault Current in 2011 (Unit: kA)

Table 2.2-4 Maximum Fault Current by Voltage Class

Voltage (kV) Station Fault current (kA)

400 Maputo 9.8
275 Maputo 6.5
132 Mozal 19.3
110 Corumana 1.0
66 Infulene 12.8
(Source: Analysis results using PSSE network data provided by EDM)

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2.3 Power Demand Forecast and Development Plan

2.3.1 Geographical Scope

The national power system in Mozambique is geographically separated into three regional
systems of the Northern, Central, and Southern regional systems respectively. There is a 220kV
interchange transmission line between the Northern and Central regional systems while the
Southern regional system is independently operated without any interchange power from the
others, but it is interconnected with the South African grid with the supplied power originally
generated at Cahora Bassa HPP (2,075 MW).

The Northern regional system is operated by ATNO (Nampula) while the Central regional
system is operated by the two operators of ATCN (Quelimane) and ATCE (Chimoio) whose
supply areas are geographically defined. In the Southern regional system, ATSU (Maputo) is the
only system operator (refer to Figure 2.3-1). In making power demand forecasts, therefore,
power consumption is estimated by each regional system and summed up as the national power
demand for the whole country.

The Backbone Transmission Project is planned to come into operation in the early 2020s,
although starting operation had originally been expected in 2017. Thereby, the desired power
transmission line between the Central and Southern regional systems is no longer expected to
start during this decade to enable central-to-south power transmission by using some large hydro
and/ or coal-fired power sources to be developed in Tete province. The synchronization and
implementation of a variety of billion-dollar projects (like long-distance-and-multi-circuit
transmission projects and large scale hydro/thermal power projects) is quite difficult particularly
from a financial viewpoint, and EDM has expressed its opinion that many projects could be
increasingly delayed. In this context, it is recommended that power development planning in the
Southern regional system be considered independently from other regional systems with the
pursuit of supply/demand balance within the Southern system only.

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(Source: EDM)
Figure 2.3-1 Regional Power Systems in Mozambique

2.3.2 Current Supply/demand Status

Table 2.3-1 shows the data of power supply/demand balance across the country from 2007 to
2011. According to the statistics, the growth rate of power consumption over that period was
11.6% per annum while that of maximum demand was 14.1% per annum. Load factor tended to
decrease and reached by 75% in 2011. This implies that power consumption during peak time
was relatively increased and consequently load factor went down. However, 75% is still a large
number compared to other developing countries. It is, therefore, considered that load shedding
has frequently taken place during peak time in summer particularly and consequently the number
of load factor remains high.

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Maximum demand occurs every November in the summer. It also tends to peak at around 8 pm.
Mozambique has a similar lighting-demand structure as other developing countries (refer to
Figure 2.3-2).

Table 2.3-1 Power Supply/Demand Balance in Mozambique (2007 to 2011)

2007 2008 2009 2010 2011
Peak Demand (MW) 364 416 481 534 616
Load Factor 82% 83% 76% 76% 75%
Electricity Energy (GWh) 2,622 3,032 3,193 3,553 4,068
Generation 224 352 386 368 389
Purchase (mainly from HCB) 2,381 2,653 2,775 3,118 3,588
Imports (Mainly from SA) 17 27 39 67 91
Loses (T/D lins) ※ -20 -23 -26 -27 -31
Saleable Energy (GWh) 2,099 2,362 2,679 2,973 3,358
Distribution 1,561 1.632 2,077 2,297 2,547
Large Customers 15 60 88 96 101
Exports 523 670 514 580 710

(Source: EDM Demand Forecast Report, partially modified by the JICA Study Team)

(Source: EDM)

Figure 2.3-2 Load Profile for Maximum Daily Demand (November 16, 2011)

Regional power demand is shown in Table 2.3-2, however the figures of total demand are
different from those in “Saleable Energy” in Table 2.3-1. One possible reason for this difference
is that Table 2.3-1 has counted power consumption by Large Customers whereas Table 2.3-2 has
not. Meanwhile, the Southern region, including the capital city Maputo, consumes approximately
2/3 of the electric energy of the entire country. This means that ensuring a stable supply of power
to the Maputo area is essential for the further development of the country.

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Table 2.3-2 Regional Power Demand (GWh)

2005 2006 2007 2008 2009 2010 2011 AGR*

South 1,153 1,239 1,373 1,550 1,731 1,910 2,095 10.5%
Center 393 427 467 497 558 603 739 11.1%
North 190 218 244 255 302 363 428 14.5%
Total 1,736 1,884 2,084 2,302 2,591 2,876 3,262 11.1%
(Source: EDM)

Note: * Annual Growth Rate

Taking the Southern region’s power supply/demand balance into account as shown in Figure
2.3-3, power purchases from Cahora Bassa HPP (2,075 MW) have been ramped up since 1988
when EDM started buying electricity from the said HPP. In 2011, EDM bought 1,800 GWh of
electricity energy from Cahora Bassa HPP, accounting for more than 90% of the Southern
region’s power demand.

(Source: EDM Statistic Report 2011)

Figure 2.3-3 Power Supply Structure in the Southern Regional System

Under the power purchase agreement between EDM and Cahora Bassa HPP, EDM has the right
to increase the amount of “Additional Power” on a mutual agreement basis while 300 MW of
firm power is securely fixed. Table 2.3-3 shows both the actual data and projection of purchased
power from Cahora Bassa HPP, illustrating that the amount of purchased power has increased
from year to year. Moreover, EDM plans to increase purchased power by 600 MW in 2015 and
subsequently by 700 MW in 2015 or later. However, there appears to be a low likelihood of
buying additional electricity after 2015 because of insufficient surplus hydro energy.

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Table 2.3-3 Power Purchased from Cahora Bassa HPP

Year Firm Power (MW) Additional Power (MW) Energy (GWh)
2008 300 90 2,635
2009 300 100 2,775
2010 300 100 3,022
2011 300 200 3,549
2012 (planned) 300 200 4,205
2013 (planned) 300 200 4,205
2014 (planned) 300 300 4,993
2015 - (planned) 300 400 5,782
(Source: EDM)

2.3.3 Power Demand Forecast

Power demand forecasts are referred to in the report of Technical Assistance to Strengthen
EDM’s Capacity for Investment and Network Development Planning – Master Plan Update
Project, Load Forecast Report, August 7, 2012, funded by IDA, AFD, EIB, and AGFUND in the
course of the Mozambique National Energy Development and Access Program (“NEDAP”, 5
years, US$215 million). The report foresees power demands for general customers and large
customers respectively, and shows the total expected power demand from 2012 to 2026. Power
demand for general customers is calculated with a statistical formula using several economic
parameters like GDP growth rate, GDP elasticity, and electricity price elasticity. The figures of
GDP growth rate are derived from official announcements of the Ministry of Planning and
Investment assuming that it remains 6%/year on average across the country, and partly 7%/year
in the higher developing areas and 5%/year in other slower growing areas.

In respect to power demand forecasts for large consumers, each and every potential key project
consuming power at more than 2 MW has been listed and summarized. The key projects are
aluminum smelters, natural gas/ coal/ other natural resource developers, large agro-industries and
relevant infrastructure industries.
The report also refers to three cases of demand forecast such as Base case, High case, and Low
case in consideration of any deviation of power demand for key projects and regional economic
growth.

Figure 2.3-4 shows three regional demand forecasts. The Southern region, including Maputo city,
is one of the fastest growing areas in Mozambique where power demand is expected to increase
by 2.2 times in 5 years and 2.7 times in 10 years. Figure 2.3-5 shows the Southern region’s
demand forecast by each economic development case.

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1400
North Demand Forecast (Base Case)
1200
Central
South
1000
Power Demand (MW)

800

600

400

200

0
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026

(Source: Master Plan Update Project, Load Forecast Report, August 7, 2012)

Figure 2.3-4 Regional Demand Forecast by Base Case

1600
High Demand Forecast (South Region)
1400
Low
1200 Base
Power Demand (MW)

1000

800

600

400

200

0
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026

(Source: Master Plan Update Project, Load Forecast Report, August 7, 2012)

Figure 2.3-5 Southern Region’s Demand Forecast by Development Case

2.3.4 Power Development Plan

(1) Outline of EDM’s Power Development Plan

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EDM and Norconsult have jointly prepared the “Generation Master Plan for the Mozambican
Power Sector” of which the first draft was issued in July 2009. The Master Plan reflects
large-scale hydropower projects in the Zambezi river system and coal-fired power projects
adjacent to the planned coal mining projects in Tete province, synchronizing the construction of
the DC/AC transmission line projects with a total capacity of 6,000 MW. This is the so-called
Backbone Transmission Project which would substantially have a strong impact on EDM’s
power development plan. With huge financial costs of approximately US$2.8 billion, the
Backbone Project is a massive multi stakeholders’ project. Therefore, EDM is of the opinion that
some relevant institutions have not anticipated the timely implementation of the project. It is, for
example, assumed that the coal-fired power projects in Tete province are vulnerable in their
timely operation as the project owner, Vale, one of the world’s biggest mining companies, may
be significantly affected by the status of their core mining business and may potentially make the
decision to delay the project if global coal markets fall. In this regard, the Backbone Project is
NOT a reliable project for the purpose of stable power supply at this point in time.
Assuming all the power generation projects along with the Backbone Project are successfully put
into operation, the power output from the projects will largely exceed the power demand in
Mozambique. This requires careful preparation and arrangements between EDM and the
owners/operators of the Backbone Project in terms of sale of surplus energy to other countries,
long-term shutdown of aged power plants, and particularly power system operation including
interconnections with neighboring countries. However, such preparation work has not progressed
yet because the projects have low likelihood of implementation so far.

In this regard, EDM is still seeking a practical power development plan 1 with no uncertainty of
the above-mentioned issues. At the working level, Figure 2.3-4 and Figure 2.3-5 are considered
as a likely power development scenario of power supply/demand balance in kW and kWh. In this
plan, part of the generation capacity of Mpanda Nkuwa HPP (1,500 MW) is expected to be put
into operation in 2019 while other large projects are still under consideration on whether or not
to reflect to EDM’s power development plan.

In addition, some medium-scaled hydropower projects across the countries are planned to start
operation during the next few decades. As to thermal power projects, two IPPs such as Benga

1
The CTM is to be commissioned in 2016 under the EDM’s practical power development plan. It is emphasized that
even if EDM is successfully able to start commissioning the CTM project in 2016, the power shortage will not be
solved. This report, however, indicates that the commissioning year of the CTM project will be 2018 based on a
realistic schedule.

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(coal, 250 MW) and Moatize (coal, 300 MW) are to start operations in 2016 with only 50 MW
respectively. In this power development plan, it is worth mentioning that the assumption was
made that the Backbone Transmission Project was not expected to start operation. It was
assumed that only the interconnected transmission line would be in operation, by which
electricity from Cahora Bassa HPP is transferred to the Southern regional system via the South
African Power Grid. Therefore, electricity generated by the power projects planned in the
Northern/Central areas is to be transferred and then distributed to the Central and Northern
regional systems first through the existing interchange transmission line. Subsequently,
remaining electricity, that may be limited, could be transferred to the Southern regional system
via the South African Power Grid.

(2) Supply/Demand Balance in kW (Capacity Balance)

Since there is no interchange transmission line between the Southern regional system and the
Central/Northern regional systems, each regional power supply/demand balance was examined
independently.
Figure 2.3-6 is a cumulative graph showing maximum power demand forecast and supply
capacity planned (with some actual figures partially recorded) from 2010 to 2026 in the
Northern/Central areas. In 2014 to 2018, minor power shortage is expected, however power
generation capacity appears to be strong after 2019 when Mpanda Nkuwa HPP and other projects
start commercial operation. However, the question remains about the reserve margin of the
Northern/Central systems to ensure stable power supply. Since these supply/demand balances
have been examined on installed capacity basis, it would be better to consider a proper number
of reserve margin. Because the data of planned/forced outages and transmission/distribution
losses are not available in the Mozambican power sector, the JICA Study Team has assumed that
the desirable number of reserve margin is 1.2 from its technical experience in power system
planning. In consideration of the reserve margin of 1.2, in the period of 2014 to 2018 there would
be severe power shortages during the peak time/season and moreover in the period after 2019
there would no longer be any electric power transferred to the Southern regional system.
In the Southern regional system, power supply/demand in kW will not be in equilibrium without
importing peak power from the South African Power Grid at the peak time over all periods of the
analysis. The capacity of CTM-CCGT can make a great contribution to relieve the dependency
of Mozambique from importing costly peak power (refer to Figure 2.3-7). Meanwhile, the
amount of imported peak power from the South African Power Grid will be 400MW at most, and
that is quite small compared to the power demands of South Africa.

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(Source: JICA Study Team)

Figure 2.3-6 Northern/Central Regions’ Supply/Demand Balance in kW (Demand:

Base)

1400
Southern Power Shortage (=Requirement for imported power from SAPP)
Southern Interchange Power (incoming: +)
1200
Maximum Demand / Supply Capacity (MW)

Southern Supply Capacity w/o CTM-CCGT

Southern Supply Capacity (CTM-CCGT)
1000
Southern Maximum Demand

800

600

400

200

0
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026

(Source: JICA Study Team)

Figure 2.3-7 Southern Regions’ Supply/Demand Balance in kW (Demand: Base)

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In the low demand case, power supply/demand can be equalized with less imported peak power
compared to the base demand case. However, the chance remains of peak power shortage
potentially after 2019 even if CTM-CCGT starts operation in 2016.

In summary, CTM-CCGT is essential to secure the capacity balance in the Southern regional
system until 2026 at the least. This project can contribute to reduce the likelihood of any power
shortages during peak time/season and the amount of importing costly peak power from the
South African Power Grid.

1200
Southern Power Shortage (=Requirement for imported power from SAPP)
Southern Interchange Power (incoming: +)
1000
Maximum Demand / Supply Capacity (MW)

Southern Supply Capacity w/o CTM-CCGT

Southern Supply Capacity (CTM-CCGT)
800 Southern Maximum Demand

600

400

200

0
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026

(Source: JICA Study Team)

Figure 2.3-8 Southern Region’s Supply/Demand Balance in kW (Demand: Low)

(3) Supply/Demand Balance in kWh (Energy Balance)

Figures 2.3-9 and 2.3-10 are cumulative graphs showing power consumption forecast and power
supply planned (with some actual figures partially recorded) from 2010 to 2026 in the
Northern/Central areas. Cahora Bassa HPP (in operation) and Mpanda Nkuwa HPP (expected
operation start in 2019) are to contribute sufficient power supply to the Northern/Central areas.
However, one point to be considered is that this estimate was made based on installed capacity
and higher plant factor (=0.95) according to EDM’s plan.

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Figure 2.3-11 illustrates the energy demand/ supply balance in the Southern region. Even if the
power plants were operating at their full capacity, the Southern regional system would face a
critical power shortage situation in the period until 2018 just before Mpanda Nkuwa HPP starts
operation. After 2019, it is assumed that there is still the potential of a lack of power supply in
the South, provided that the power plants are operated in an ordinary manner with time for
regular maintenance and monitoring the actual conditions of river water flow to the dams. In any
case, the electricity energy generated at CTM-CCGT (assumed at 100 MW) is essential for
securing stable energy supply.

(Source: JICA Study Team)

Figure 2.3-9 Northern/Central Regions’ Supply/Demand Balance in kWh (Demand:

Base)

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12000
Southern Power Shortage (=Requirement for imported power from SAPP)
Southern Interchange Power (incoming: +)
10000
Southern Supply w/o CTM-CCGT
Southern Supply (CTM-CCGT)
Electricity Energy (GWh)

8000 Southern Demand

6000

4000

2000

0
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026

(Source: JICA Study Team)

Figure 2.3-10 Southern Region’s Supply/Demand Balance in kWh (Demand: Base)

For the case of low demand, Figure 2.3-11 presents the supply/demand balance in kWh in the
Southern regional system. It is clearly shown that over the period of 2010 to 2026 the amount of
power shortage can be decreased. After 2019, it is expected that lower efficient thermal power
projects need to be in standby mode and generate electricity during peak time/season. The
CTM-CCGT project, with its much higher thermal efficiency, would need to continue operation
as a base power supply source even in the case of low demand.

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12000
Southern Power Shortage (=Requirement for imported power from SAPP)
Southern Interchange Power (incoming: +)
10000
Southern Supply w/o CTM-CCGT
Southern Supply (CTM-CCGT)
Electricity Energy (GWh)

8000 Southern Demand

6000

4000

2000

0
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026

(Source: JICA Study Team)

Figure 2.3-11 Southern Region’s Supply/Demand Balance in kWh (Demand: Low)

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Table 2.3-4 Supply/Demand Balance in kW (Demand: Base Case)

(Unit: MW) 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026
Northern Maximum Demand (Base) 87 85 93 138 206 262 311 404 457 480 487 492 500 508 517 527 537
Supply Capacity 0 0 0 0 0 0 0 0 60 180 180 180 180 180 180 180 180
-Alto Malema HPP (60 MW) 60 60 60 60 60 60 60 60 60
-Lurio HPP (120 MW) 120 120 120 120 120 120 120 120
Interchange Power (incoming: +) 87 85 93 138 175 188 296 329 315 300 307 312 320 328 337 347 357
Balance (shortage: -) 0 0 0 0 -31 -74 -15 -75 -82 0 0 0 0 0 0 0 0
Power Shortage 0 0 0 0 31 74 15 75 82 0 0 0 0 0 0 0 0
Central Maximum Demand (Base) 128 154 246 372 462 549 590 557 571 587 604 619 636 651 665 678 694
Supply Capacity 468 568 568 537 637 737 886 886 886 1,336 1,336 1,336 1,336 1,336 1,336 1,336 1,336
-Chicamba HPP (38 MW) 38 38 38 12 12 12 44 44 44 44 44 44 44 44 44 44 44
-Mavuzi HPP (42 MW) 30 30 30 25 25 25 42 42 42 42 42 42 42 42 42 42 42
-Cahora Bassa HPP (2,075 MW) 400 500 500 500 600 700 700 700 700 700 700 700 700 700 700 700 700
-Cahora Bassa North HPP (1,245 MW)
-Mpanda Nkuwa HPP (1,500 MW) 150 150 150 150 150 150 150 150
-Benga Coal TPP (250 MW) 50 50 50 50 50 50 50 50 50 50 50
-Moatize Coal TPP (300 MW) 50 50 50 50 50 50 50 50 50 50 50
-Mavuzi HPP (60 MW)
-Lupanta HPP (600 MW) 200 200 200 200 200 200 200 200
-Boroma HPP (200 MW) 100 100 100 100 100 100 100 100
Interchange Power (incoming: +) -340 -414 -322 -165 -175 -188 -296 -329 -315 -749 -732 -717 -700 -685 -671 -658 -642
Balance 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Southern Maximum Demand (Base) 344 369 407 488 587 687 794 876 932 976 1,009 1,043 1,080 1,118 1,159 1,201 1,245
Supply Capacity 16 16 81 88 421 356 406 456 456 456 456 456 456 456 456 456 456
-Corumana HPP (14 MW) 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16
-CTM Existing GTPP (52 MW) 50 50
-Temane GTPP (7-62 MW) 7 12 12 12 62 62 62 62 62 62 62 62 62 62
-Aggreko GTPP (65 MW) 65 65 65
-Ressano Sasol-EDM (140 MW) 140 140 140 140 140 140 140 140 140 140 140 140 140
-Ressano Gigawatt-Mozambique (100 MW) 100 100 100 100 100 100 100 100 100 100 100 100 100
-Kuvaninga GTPP (38 MW) 38 38 38 38 38 38 38 38 38 38 38 38 38
-Massingir HPP (30 MW)
-CTM CCGT (100 MW) 100 100 100 100 100 100 100 100 100 100 100
Interchange Power (incoming: +) 253 329 229 27 0 0 0 0 0 449 425 405 380 357 334 311 285
Power Shortage (= Requirement for
75 24 97 373 166 331 388 420 476 71 128 182 244 305 369 434 504
imported power from SAPP)
Balance 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Total (Country) Maximum Demand 559 608 746 998 1,255 1,498 1,695 1,837 1,960 2,043 2,100 2,154 2,216 2,277 2,341 2,406 2,476
Supply Capacity 484 584 649 625 1,058 1,093 1,292 1,342 1,402 1,972 1,972 1,972 1,972 1,972 1,972 1,972 1,972
Power Shortage (= Requirement for
75 24 97 373 166 331 388 420 476 71 128 182 244 305 369 434 504
imported power from SAPP)
Balance 0 0 0 0 -31 -74 -15 -75 -82 0 0 0 0 0 0 0 0
(Source: EDM and some estimations by the JICA Study Team)

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Table 2.3-5 Supply/Demand Balance in kWh (Demand: Base Case)

(Unit: GWh) 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026
Northern Demand (Base) 447 494 531 808 1,066 1,655 1,991 2,661 3,003 3,147 3,186 3,208 3,252 3,297 3,346 3,397 3,450
Supply 0 0 0 0 0 0 0 0 499 1,498 1,498 1,498 1,498 1,498 1,498 1,498 1,498
-Alto Malema HPP (60 MW) 499 499 499 499 499 499 499 499 499
-Lurio HPP (120 MW) 999 999 999 999 999 999 999 999
Interchange Power (incoming: +) 447 494 531 808 1,066 1,655 1,991 2,661 2,504 1,649 1,688 1,710 1,754 1,799 1,848 1,899 1,952
Balance (shortage: -) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Central Demand (Base) 617 678 1,143 1,714 2,229 2,699 2,918 2,614 2,675 2,742 2,818 2,877 2,952 3,020 3,083 3,134 3,204
Supply 3,644 4,485 4,485 4,357 5,145 5,934 6,968 6,968 6,968 10,712 10,712 10,712 10,712 10,712 10,712 10,712 10,712
-Chicamba HPP (38 MW) 156 156 156 49 49 49 181 181 181 181 181 181 181 181 181 181 181
-Mavuzi HPP (42 MW) 124 124 124 103 103 103 173 173 173 173 173 173 173 173 173 173 173
-Cahora Bassa HPP (2,075 MW) 3,364 4,205 4,205 4,205 4,993 5,782 5,782 5,782 5,782 5,782 5,782 5,782 5,782 5,782 5,782 5,782 5,782
-Cahora Bassa North HPP (1,245 MW)
-Mpanda Nkuwa HPP (1,500 MW) 1,248 1,248 1,248 1,248 1,248 1,248 1,248 1,248
-Benga Coal TPP (250 MW) 416 416 416 416 416 416 416 416 416 416 416
-Moatize Coal TPP (300 MW) 416 416 416 416 416 416 416 416 416 416 416
-Mavuzi HPP (60 MW)
-Lupanta HPP (600 MW) 1,664 1,664 1,664 1,664 1,664 1,664 1,664 1,664
-Boroma HPP (200 MW) 832 832 832 832 832 832 832 832
Interchange Power (incoming: +) -3,027 -3,807 -3,342 -2,643 -2,916 -3,235 -4,050 -4,354 -4,293 -7,970 -7,894 -7,835 -7,760 -7,692 -7,629 -7,578 -7,508
Balance 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Southern Demand (Base) 1,897 2,085 2,324 2,784 3,402 4,070 4,855 5,460 5,799 6,055 6,242 6,438 6,646 6,864 7,095 7,337 7,591
Supply 66 66 66 95 2,188 2,805 3,254 3,680 3,680 3,680 3,680 3,680 3,680 3,680 3,680 3,680 3,680
-Corumana HPP (14 MW) 66 66 66 66 66 66 66 66 66 66 66 66 66 66 66 66 66
-CTM Existing GTPP (52 MW) 146 350
-Temane GTPP (7-62 MW) 29 51 76 87 513 513 513 513 513 513 513 513 513 513
-Aggreko GTPP (65 MW)
-Ressano Sasol-EDM (140 MW) 777 1,165 1,165 1,165 1,165 1,165 1,165 1,165 1,165 1,165 1,165 1,165 1,165
-Ressano Gigawatt-Mozambique (100 MW) 832 832 832 832 832 832 832 832 832 832 832 832 832
-Kuvaninga GTPP (38 MW) 316 316 316 316 316 316 316 316 316 316 316 316 316
-Massingir HPP (30 MW)
-CTM TPP (100 MW) 788 788 788 788 788 788 788 788 788 788 788
Interchange Power (incoming: +) 2,580 3,313 2,811 1,835 1,850 1,580 2,059 1,693 1,789 6,321 6,206 6,125 6,006 5,893 5,781 5,679 5,556
Power Shortage (= Requirement for
0 0 0 854 0 0 0 87 330 0 0 0 0 0 0 0 0
imported power from SAPP)
Balance 749 1,294 553 0 636 315 458 0 0 3,946 3,644 3,367 3,040 2,709 2,366 2,022 1,645

Total (Country) Maximum Demand 2,961 3,257 3,998 5,306 6,697 8,424 9,764 10,735 11,477 11,944 12,246 12,523 12,850 13,181 13,524 13,868 14,245
Supply Capacity 3,710 4,551 4,551 4,452 7,333 8,739 10,222 10,648 11,147 15,890 15,890 15,890 15,890 15,890 15,890 15,890 15,890
Power Shortage (= Requirement for
0 0 0 854 0 0 0 87 330 0 0 0 0 0 0 0 0
imported power from SAPP)
Balance 749 1,294 553 0 636 315 458 0 0 3,946 3,644 3,367 3,040 2,709 2,366 2,022 1,645
(Source: EDM and some estimations by the JICA Study Team)

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2.4 Outline of Cooperation Projects Implemented by Other Donor Agencies

The Ministry of Energy (“ME”), which holds jurisdiction over the power sector in Mozambique,
and EDM, which is the publicly-owned electricity company under the jurisdiction of the ME,
with the support from foreign countries, have engaged in human capacity building, the
establishment of policy and regulatory framework of the Mozambican power sector, and the
development and operation of power equipment and facilities. This chapter provides an outline
of power projects implemented (or to be implemented) in cooperation with other donor
agencies.

2.4.1 On-going Power Projects

Table 2.4-1 shows the on-going power projects in Mozambique, classified into three categories:
technical cooperation projects, transmission projects, and rural electrification projects, with total
project costs amounting to USD 669.19 million.

The technical cooperation projects are supported by aid agencies such as the World Bank
(“WB”), International Development Association (“IDA”), L'Agence Française de
Développement (“AFD”), the Government of Norway (through the Agency for Development
Cooperation, “NORAD”) and the Government of Sweden (through the Swedish International
Development Cooperation Agency, “SIDA”). The technical cooperation projects for the power
sector are characterized by the wide range of aid agencies and countries involved.

The Mozambique Electricity Master Plan was prepared with the assistance of NORAD in 2004.
In 2008, however, the need to upgrade the Master Plan was recognized so terms of reference
(“TOR”) for an update of the previous Master Plan were prepared. Currently, the Master Plan is
being updated to be completed by April 2013. Sub-Item 1.1.3: "Update of Master Plan 2010 -
2027" in Table 2.4-1 corresponds to this project.

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Table 2.4-1 On-going Power Projects

Cost
Item Name of the Project Funder
[MUSD]

1. Ongoing projects
1.1 Feasibility Study and Technical Assistance
1 Feasibility Study of Second Line Caia - Nampula 1.80 IDA
2 Integrated Management System (Sigem) 6.74 IDA
3 Update of Master Plan 2010-2027 1.30 AFD
4 Capacity Building 4.00 Swedish
5 Feasibility Study for Electrification of Vilanculos (OHL 110 kV Chibabava - Vilankulos) 0.05 Swedish
Sub Total - Item 1.1 13.84
1.2 Transmission Projects
1 Rehabilitation and Reinforcement of Distribution network. Maputo City (Lot 1) 33.35 Portugal
2 Rehabilitation and Reinforcement of distribution network. Maputo City (Lot 2) 31.90 Portugal
3 Mobil Substation 6.09 Reino Belga
4 66kV Lines in Maputo 6.65 EDM
5 Mixed credit 150.00 Danida
6 Assembly of the Second Transformer in Matambo SS 13.00 World Bank
7 110kV Transmission Line Mavuzi - Chibabava 19.50 EU
8 SVC in Mocuba 10.03 GdM
9 Rehabilitation Chimoio SS and Acquisition of Mobile SS 110/33/22 kV 10 MVA 6.30 Kingdom of Belgium
10 Electricity II (Line DL8) 0.40 EDM
11 Electricity IV (Chibata - Dondo 220kV) 55.00 ADB/OPEC
12 Rural Electrification of North area of Gaza Province (110kV Lionde - Mapai) 54.00 Korean Exim Bamk
13 Transmission line 275 KV Corumana - Lionde 25.30 Danida
Sub Total - Item 1.2 386.22
1.3 Rural Electrification Projects
1 LCREP of Niassa 11.40 IDB
2 EDAP (Expansion MV Network in Maputo, Manica, Tete, Nampula and Cabo Delgado) 147.70 BM/Afund/OFID/AFD/EIB
3 Rural Electrification Sofala, Manica and Tete Provinces (Lot B) 15.80 Suecia/Noroega
4 Rehabilitation of Bilene SS 1.90 EDM
5 Rural Electrification of Inhambane, Zambezia and Nampula Provinces 30.00 EXIM BANK/INDIA
6 Rural Electrification of Niassa, Cabo Delgado and Manica Provinces 25.00 EXIM BANK/INDIA
7 Electricity III 19.33 ADB/OPEC
8 Rural Electrification of Cabo Delgado Phase III - Addendum (Ibo) 13.00 NORWAY
9 Rural Electrification of Pande 3.00 GoM
10 Rural Electrification of Chimbonila 2.00 Norway
Sub Total - Item 1.3 269.13
TOTAL - Item 1 669.19

(Source: EDM, 2012)

2.4.2 Priority Projects without Funding

Table 2.4-2 shows the priority power projects to be implemented in accordance with the power
development plan for which a funding source has not been determined. This table shows only
the projects to be implemented over the period 2010 - 2015. The projects are divided into four
categories: transmission projects, rural electrification projects, distribution and rehabilitation
projects, and generation projects with a total project cost expected to amount to USD 2,906.07
million. Although some transmission projects have already gained financial commitment, most
of the projects still require a large amount of funds for implementation, thus requiring financial
support from developed countries.
The Beluluane Gas-Fired Power Plant Project requested by the Government of Mozambique
through ME and EDM corresponds to Sub-Item 2.10.2: “1. Beluluane 50 MW Gas Fired Power
Plant: 75 MUSD.” In addition, the Project for Rehabilitation of the existing Maputo Thermal
Power Plant corresponds to Sub-Item 2.10.2 “10. Expansion of Gas Turbine HRSG Coupled to
Existing Plant: 70 MUSD.” Both are designated as priority projects to be implemented.

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Table 2.4-2 Priority Projects Without Any Funding

Cost
Item Name of the Project Remarks
[MUSD]
2. . Priority Projects Without Funding
2.1 Transmission Projects (2010 - 2015)
1 Rehabilitation and Reinforcement of Infulene SS 32.00
2 Rehabilitation and Reinforcement of Transmission Net grid in Maputo 4.70
3 Transmission line 275 kV Infulene - Maputo 50.80
4 Rehabilitation and Reinforcement of Maputo SS and Power Transfer to South Area 96.68
5 Transmission line 275 kV Maputo - Salamanga and Salamanga 66/33 kV SS Extension 48.59 committed
6 Transmission Line 66kV Salamanga - Catembe 24.12
7 Reinforcement of Maputo Transmission Capacity (SS Costa do Sol) 47.70
8 Interconnection of Moamba Gas Plant (750 MW) to 275 kV Network 750.00
9 Reinforcement of Chicumbane SS and Interconnection of 275 KV Lionde SS 35.40
10 Reinforcement the Network of Major Corridors 66 kV of Maputo 30.00
11 Interconnection SE1, 3, 5 and Facim - to 66 kV SE5 9.55
12 Construction of FACIM SE and interconnection CTM, SE and SE1 20.00
13 Rural Electrification of Vilanculos (OHL 110 kV Chibabava - Vilankulos) 42.10 committed
14 110 kV Transmission Line Vilankulos - Massinga 32.80
15 Manga Substation 21.17
16 Reinforcement of Chimoio substation 20.17
17 Reinforcement the Network of Tete 38.40
18 SVC North System 19.00 committed
19 Reinforcement of Caia - Nampula - Nacala 220 kV 312.20
20 Reinforcement of Nampula Transmission System (Namialo SS) 12.05
21 Reinforcement of 220/110 kV Substation (System Center - North) 21.00 committed
22 Central Dispatch Center / North 30.09 committed
Sub Total - Item 2.1 1,698.52
2.2 Rural Electrification Projects (2010-2015)
1 Rural Electrification of Niassa province - Phase III (Mecula and Nipepe) 36.90
2 Electrification of Border Villages of Niassa, Zambezia, Tete, Manica and Maputo Provinces 49.30
3 Rural Electrification and Urban Maputo Province 63.04
4 Rural Electrification of Vilanculos 39.34
5 Rural Electrification of Sofala North Administrative Posts 11.03
6 Rural Electrification of Balama, Namuno and Machaze 25.00
7 Agricultural Areas Electrification in Mozambique 128.30
Sub Total - Item 2.2 352.91
2.3 Distribution & Rehabilitation Projects (2010-2015)
1 Rehabilitation of Lichinga Distribution Network - Niassa Province 14.60
2 Rehabilitation of Nampula Distribution Network - Nampula 16.34
3 Reinforcement and Expansion of Nacala Distribution Grid 20.02
4 Rehabilitation of Beira Electrical Network 8.08
5 Rehabilitation of Xai-Xai Distribution Networks - Gaza Province 11.97
6 Reinforcement of Matola Network 31.44
7 Rehabilitation and Reinforcement of Maputo Distribution Network 30.00
8 Reinforcement the surrounding Maputo Network Package 2 39.72
9 Reinforcement end Extension of Maputo Netgrid Phase I 2011 17.51
10 Reinforcement end Extension of Maputo Netgrid Phase II 2011 21.67
11 Loss Reduction Project in Maputo Distribution Area (Guava) 21.77
12 Ring Fance Project in Matola Area 10.02
Sub Total - Item 2.3 243.14
2.4 Generation Projects
1 Beluluane 50MW Gas Fired Power Plant 75.0
2 Moamba 120MW Gas Fired Power Plant 150.0
3 Mocimboa da Praia 50 MW Gas fired power plant 90.0
4 Kuvaninga 50MW Gas Fired Power Plant 75.0
5 Temane 10MW Gas Fired Power Plant 15.0
6 Feasibility Study for Revue Basin ( Tsate, Mueneze, Mavuzi II & III) 1.5
7 Feasibility Study of Pavue at Pungue River 1.5
8 Feasibility Study Mutelele at Ligonha River 0.7
9 Conversion of Diesel Generator to Gas Turbine 12.0
10 Expansion of Gas Turbine HRSG Coupled to Existing Plant 70.0
11 Feasibility Study for Buzi Gas usage for Electricity Generation 0.2
12 Feasibility Study for Condensates Usage from Natural Gas for Electricity Generation 0.2
13 Feasibility Study for Corrumana Hydropower Rehabilitation 0.2
14 Feasibility Study for Expansion of Temane Gas Power Plant 0.2
15 Alto Malema Basin 120.0
Sub Total - Item 2.4 611.50
Total - Item 2 2,906.07

(Source: EDM, 2012)

2.4.3 Recently Completed Projects

Table 2.4-3 shows recently completed power projects, which are separated into two categories:

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transmission projects and rural electrification and distribution projects. Total project costs
amount to USD 385.51 million.

Similar to the case for on-going transmission projects and rural electrification projects described
in Subsection 2.10.1, the projects have been implemented with the support from a wide range of
foreign countries and aid agencies.

Table 2.4-3 Recently Completed Projects

Cost
Item Name of the Project Funder
[MUSD]
3. Recently Concluded Projects
3.1 Transmission Projects Recently Completed
1 Feasibility Study of the Central - South Line (CESUL) 6.00 IDA/Noroega
2 Paiol Explosion – Supply Transformer For Chicumbane 0.78 Dinamarca
3 Matola Substation 275/66kV 18.50 KUWAIT/OPEC
4 National Dispatch Center 5.10 DANIDA
5 Commissioning of 2º Transformer at Machava Substation 0.38 BDSA
6 Creation of the Environmental Unit 0.54 DANIDA
7 Rural Electrification of Marromeu 9.60 KfW/EdM
8 Project of the 110kV Transmission Line Nampula - Pemba 6.80 BADEA/ IDB/ EDM
9 Rural Electrification of Cabo Delgado Phase II 10.25 BADEA/BID
10 Gurue - Cuamba - Lichinga - 110kV Transmission Line 46.43 Suecia/Noroega
11 Feasibility Study for Electrification of Niassa (Cuamba - Marrupa 110kV Line) 0.40 BADEA
12 Rural Electrification of Cabo Delgado Phase III 53.00 NORWAY/BADEA/BID/EU
13 Alto Molocue - Uape - 110kV Transmission Line 9.96 EXIM BANK - India
Sub Total - Item 3.1 167.74
3.2 Rural Electrification & Distribution Projects Recently Completed
1 ERAP Package I, II and III, Extension of Distribution Networks 14.91 BAD
2 Rehabilitation of Maputo and Matola 7.77 ICO/SPAIN
3 Service connection in Matola City 3.00 GTZ
4 Connection of 12,000 consumers in the area of Maputo and Matola 3.00 GTZ
5 Increasing Number of Consumers in Matola Area 10.50 Elswedy-Egipto
6 Rehabilitation and Reinforcement of Infra infrastructures Damaged by Paiol Explosion 4.30 DANIDA
7 Rehabilitation and Reinforcement of Maputo Distribution Net Work 23.50 DANIDA
8 Rural Electrification of Gaza Province 19.95 EXIM BANK - India
9 Rural Electrification of Morrumbene and Massinga 1.60 Dinamarca
10 LCREP of Inhambane (Massinga - Morrungulo) 11.40 Dinamarca
11 Rural Electrification of Gorongosa 4.34 KFW
12 Rural Electrification of Sofala, Manica and Tete Provinces 15.80 Suecia/Noroega
13 Rural Electrification of Chibabava and Buzi Districts, Sofala Province 9.67 Suecia / Dinamarca
14 Rural Electrification of Tete Districts 32.00 GoM
15 Rural Electrification of Tete Districts - Addenda 1 & 2 10.56 EU
16 Rural Electrification of Namacurra 8.76 NORAD
17 Rural Electrification of Namacurra Pebane Extension 6.00 NORAD
18 Rehabilitation and Reiforcement of Distribution Network of Beira City 15.50 DSBA
19 Rural Electrification of Mecanhelas, Maua, Metarica and Marrupa, Niassa Province 14.00 Suecia/Noroega
20 Rural Electrification of Sanga - Niassa Province 1.21 GoM
Sub Total - Item 3.2 217.77
Total - Item 3 385.51
(Source: EDM, 2012)

2.4.4 Scale of Project Costs

A simple sum of all project costs listed in Subsections 2.10.1, 2.20.2 and 2.10.3 adds up to USD
3,800 million as shown in Table 2.4-4. The sum of the costs of the on-going projects and the
recently completed projects accounts for only 27.8% of the total project costs. The projects to be

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implemented by 2015 (listed in Section 4.2) still require a large amount of investment. For the
recently completed projects, the project costs incurred by ME and EDM account for 10.1% of
the total amount with the rest dependent on foreign aid. As this trend continues, both
government-based support from other countries and private investment are considered essential
for the future of the power sector of Mozambique.

Table 2.4-4 Total Investment Amount in Power Sector

Category Amount (MUSD) %
On-going projects 669.2 17.6%
Priority projects without funding 2,745.3 72.2%
Recently completed projects 385.5 10.1%
Total 3,800.0 100.0%
(Source: EDM, 2012)

As mentioned in Subsection 2.10.2, the total project costs for priority power projects without
funding amounts to USD 2,745.3 million with the breakdown shown in Table 2.4-5 and
Figure 2.4-1. The cost of transmission projects accounts for the largest share (56.0%), followed
by generation projects (22.3%). However, the sources of funding necessary to implement these
projects have still not been identified.

Table 2.4-5 Priority Power Projects without Funds

Category Amount (MUSD) %
Transmission projects 1,537.7 56.0%
Rural electrification projects 352.9 12.9%
Distribution & rehab projects 243.1 8.9%
Generation projects 611.5 22.3%
Total 2,745.3 100.0%
(Source: EDM, 2012)

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Project Scale by Category for Projects without Funding

Transmission
611.5, 22% projects
Rural electrification
projects
Distribution & rehab
projects
243.1, 9% Generation projects
1,537.7, 56%

352.9, 13%

(Source: EDM, 2012)

Figure 2.4-1 Breakdown of Priority Power Projects without Funding

2.4.5 Assistance to the Mozambican Power Sector by International Aid Agencies

WB, in cooperation with IDA, has provided assistance to the Mozambican power sector. The
most recent case is the “Energy Development and Access Project (EDAP APL-2)”, which
primarily aims at improving the access rate to electricity and the quality of power supply in rural
and peri-urban areas. The project extends for five years from 2010 to 2015 and the total project
cost is expected to reach USD 80 million. The project has the following three components:
 Reinforcement of the Primary Networks and Grid Extension Component (USD 50.0 million)

 Investments in Rural and Renewable Energy Component (USD 18.0 million)

 Energy Sector Planning, Policy and Institutional Development Component (USD 10.2
million)

WB is also providing support for the “Mozambique Regional Transmission Backbone Project
(CESUL)” in collaboration with NORAD. Figure 2.4-1 shows the locations of the
above-mentioned WB assisted projects as well as other major power projects. The project
information on the above-mentioned “EDAP APL-2” and information on WB’s assistance
program for the Mozambican power sector are detailed in the following document:
 Project Appraisal Document on a Proposed Credit in the Amount Of SDR 49.7 Million (US
$80 Million Equivalent) to the Republic of Mozambique for an Energy Development and
Access Project (APL-2) (January 6, 2010)

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2.4.6 Assistance to the Mozambican Power Sector by Norway

Norway is one of the developed countries that is most actively involved in assistance to the
Mozambican power sector, and it currently provides support to the following six projects:
 Institutional Capacity Building in the Ministry of Energy, 2007–2010, Norwegian Krone
(“NOK) 41 million
 Technical Assistance to Electricidade de Moçambique, 2008–2010, NOK 13 million
 Cabo Delgado Electrification Project, 2006–2013, NOK 342 million
 Marrupa-Cuamba-Mecanhelas Electrification Project, 2007–2012, NOK 41 million
 Chimbonila Electrification Project, 2011–2012, NOK 11 million
 Support to the National Energy Fund (“FUNAE”), 2010–2011, NOK 3 million

As a member of the International Cooperation Partner (“ICP”) countries, Norway has taken a
leading role in dealing with common issues shared by the Southern African Development
Community (“SADC”), which Mozambique is affiliated with. Projects that Norway is currently
involved in are as follows:
 Support to the SADC Secretariat on Energy Related Issues
 Mozambican Regional Transmission Backbone Project (CESUL)
 Electricity Regulators’ Peer Review Network
 The Southern African Power Pool – Regional Electricity Market

2.4.7 Assistance to the Mozambican Power Sector by Germany

Germany has often provided both grant and loan assistance to the Mozambican power sector.
Among the most significant projects is the project for construction of a database regarding the
energy sector. This database is intended to capture, store and sort all the literature on the energy
sector published in the past 15 years, and the results are expected to be incorporated into this
survey. The project is being implemented by the German Agency for International Cooperation
(“GIZ”) in collaboration with Universidad Pedagogica (Pedagogica University) and it is
currently underway. It is necessary to maintain contact with GIZ, in order to obtain this database
upon its completion.

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 Chapter 3

Selection of the Site

 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Chapter 3 Selection of the Site

This chapter describes how the approximate scale of the power plant facility was estimated, how
each candidate site was compared and assessed from technological and economical viewpoints,
and how the best-suited planned construction site was selected. The selected candidate sites
were Beluluane industrial complex, which EDM had been studying, and a site on the CTM
premises from which a coal-fired power plant had been removed. The Ressano Garcia region
near PRS-1 gas decompression station was excluded as a candidate site for this survey because
the construction of a power generation facility using a gas engine had already been planned at
this site.

In addition, the following three points were considered, in respect of the views of EDM, as
prerequisites for the comparison and study:

1. Output of the CCGT power station should be maximized so that the contracted gas volume
of 6 MGJ/ year can be fully used, considering that the gas contract is a take-or-pay
contract.
2. The existing GT power station in CTM will perform base operations from 2013 to 2017
(when the CCGT power station is expected to start operation), using the contracted gas
volume of 6 MGJ/ year.
3. From 2017, the CCGT power station will fully operate and the GT power station of CTM
will operate only in the case of an emergency, e.g., if the CCGT power station stops.

3.1 Evaluation Criteria

To select one of the two prospective candidate sites above, a survey was conducted of the
evaluation items shown in Table 3.1-1 below Survey Items. These evaluation items for site
selection are generally used in order to select a thermal power station construction site and
include a comprehensive survey from the viewpoints of technology and economy.

Table 3.1-1 Survey Items for Selection of Sites for a Power Plant

Study Items Survey Items

 Site area drawing (available site area (ha), shape of site area,
Site area positional relationship with the existing facilities)
 Surplus site area for extension plans
 Distance from major highways, railways and water channels
Access  Means of transportation
 Current status of the access route

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Study Items Survey Items

 Topographic map (1/25,000 or 1/50,000)
 Geographical documentation on peripheral area, and geographical
Topographic/geo-
data on existing thermal power plants
graphical features
 Degree of difficulty in land preparation, and need of implementing
special ground improvement works
 Survey of documentation (presence or absence of rare species)
Vegetation
 Handling of mangroves
 Basic data on the natural environment around the site, e.g.,
Meteorology atmospheric temperature, humidity, precipitation, wind
direction/velocity, and atmospheric pressure
 Records of floods, high tides, and earthquakes in the power plant site
Natural disasters
area
 Distance from the water source
 Topographic features of rivers and ocean bottoms (plan view and
cross sectional view)
Cooling water and
 Long-term hydrological data (river flow, etc.)
condenser cooling
 Annual flow rate/flow rate for allowing water intake (at the time of
system
low water level), and fluctuation in water levels and water temperatures
 Data on floods and high tides
 Water quality data (when river water is used as service water)
 Distance to the industrial water supply source
Service water  Water supply capacity and water quality data
 Usage charges
 Position and route of gas pipes
 Gas properties
Fuel
 Pressure and temperature at interface point
 Fuel supply capacity and price
 Trunk network configuration
 Distance to the substation of the trunk system or the switching station
Transmission network
 Restrictions on system (current flow, short-circuit capacity and
stability)
 Presence or absence of protected areas such as National Parks and
Environmental and historic sites
social considerations  Presence or absence of precious animals and plants
(planned site for power  Relocation of inhabitants, agricultural land or cemetery in the site
plant) area
 Adaptability as an industrial area
 Presence or absence of protected areas such as National Parks and
historic sites
Evaluation of
 Presence or absence of rare animals and plants
environment impact
 Relocation of inhabitants, agricultural land or cemeteries in the site
(cooling water route)
area
 Circulation of thermal effluents
 Means of transportation (river, overland route, railroad)
 Load limits (status and load capacity of bridges and roads, and water
Transportation of heavy
depth in normal and dry season)
objects
 Dimensional limits (bridges, roads, tunnels, river widths (in dry
season))
(Source: JICA Study Team)

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3.2 Required Area for Power Plant

The JICA Study Team estimated the required area for the new power plant at each candidate site
based on a typical CCGT layout consisting of main equipment such as GTs, HRSGs and STs,
and related equipment such as gas supply equipment, water treat equipment, waste water
equipment, etc. To estimate the required area for the power plant, the following conditions were
set.

3.2.1 Setting Conditions for the Layout of the Power Plant for the Candidate Sites

(1) Maximum Power Plant Capacity

The planned new CCGT is expected to have continuous full load operation as base load
operation, and to supply electric power to meet Mozambique’s tight power demand. Based on
previous experience with CCGTs, it is assumed that the CCGT will operate continuously,
except for outages for periodic inspections (e.g., combustion inspections, hot gas pass
inspections and major inspections) and maintenance, and regular work (washing GT
compressors with water, changing generators’ brushes, etc.). The plant capacity factor is
assumed to be 83%. This CCGT plant efficiency (lower heating value, “LHV”) is estimated to
be 50%.

Power generation capacity is restricted by the volume of natural gas. The volume of gas to be
supplied to the new gas-fired power plant is 6.0 MGJ/ year at both candidate sites. Calculating
from this gas supply volume, the new power plant capacity will be approximately 114 MW.

Available generation capacity ＝ 6.0 x 106 x 109 x (50/100) /(24 x 365 x (83/100) x 3.6 x 109)

Table 3.2-1 Available Plant Capacity for Fuel

Site Beluluane CTM

Gas volume 6.0 MGJ/year 6.0 MGJ/year

Capacity 114 MW 114 MW

(Source: JICA Study Team)

(2) Required Area for Power Plant

EDM had two prospective areas for the planned CCGT. The first area was the Beluluane site,
neighboring the Beluluane transformer station, is 1.5 ha (100 m x 150 m). The second area was

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the CTM site of approximately 3.7 ha consisting of a former coal-fired power plant area and an
area of diesel oil tanks for existing GTs. One typical 110 MW class multi-shaft 2-on-1 CCGT
could be located on the Beluluane site, and two units of CCGT could be located on the CTM
site.

The results of the study are shown in Table 3.2-2 below.

Table 3.2-2 Available Power Output for Land

Site Beluluane CPM

1.5 ha
Available site area 3.7 ha
(100 m  150 m)

Maximum plant capacity 110 MW 110 MW x 2

(Source: JICA Study Team)

Air Cooled
Condencer

Gas Turbine Generator

Fuel Gas
Compressor Beluluane Substation
100m

100000

Demineralize Water Plant,

Demineralized Water Tank &
Raw Water Tank

Waste Water
Treatment
Plant
Steam Turbine Generator Heat Recovery
Steam Generator

Electrical room &

Control room

150000

150m

(Source: JICA Study Team)

Figure 3.2-1 Beluluane Site

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270m

Air Cooled
Condencer

Gas Turbine Generator

Fuel Gas

New Gas
Compressor

Station

100000
Demineralize Water Plant,
Demineralized Water Tank &
Raw Water Tank

Portable Waste Water

Treatment

Water Tie-in
Plant
Steam Turbine Generator Heat Recovery
Steam Generator

point 150000
Electrical room &
Control room

145m

125m

(Source: JICA Study Team)

Figure 3.2-2 CTM Site

(3) Conclusion

From (1) and (2) above, it is possible to install one block of multi-shaft 110MW class CCGT,
consisting of two 30 MW to 40 MW class GT generators, two HRSGs, one ST generator, and
related equipment, at both the Beluluane and CTM sites..

3.3 Land Preparation and Accessibility

The necessity for land preparation and the accessibility at CTM Maputo and Beluluane sites are
evaluated in this chapter.

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(Source: JICA Study Team)

Figure 3.3-1 Location of CTM Maputo & Beluluane Sites and Access Route from Port Maputo

3.3.1 Beluluane Site

(1) Necessity of Land Preparation

The site area is approximately 15,000 m2 (150 m x 100 m). The site is flat and there are no
obstacles to overcome to prepare the land for new power plant construction. Also, there are no
inhabitants or cultivation activities within the site.
Therefore, large-scale land preparation or resettlement is not required.

(2) Accessibility
(a) Accessibility from Port Maputo
The site is located about 20 km from Port Maputo and is adjacent to the existing Mozal
aluminum refinery. As shown in Figure 3.3-1, major trunk roads (EN1, 2 & 4) can be used for
the transportation of heavy equipment from Port Maputo to the site.

(b) Accessibility from the front road

As shown in Figure 3.3-2, the site faces the trunk road leading to the Mozal aluminum refinery.
Therefore, the construction of new access road to the site is not required.

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(Source: JICA Study Team)

Figure 3.3-2 Access from the Front Road at Beluluane Site

3.3.2 CTM Site

(1) Necessity of Land Preparation

The site is within EDM’s existing power plant site, and the total site area reserved for the new
power plant is approximately 27,000 m2. The site is flat and there are no obstacles to overcome
to prepare the land for construction. Also, there are no inhabitants or cultivation activities within
the site.
Therefore, large-scale land preparation or resettlement is not required. However, the following
issues should be given attention prior to the construction of new power plant.

(a) Existing fuel tanks

There are three existing fuel tanks that are no longer used at site, and these tanks should be
removed prior to the construction of the power plant if any equipment is to be located over the
area of these tanks.

(b) Inhabitants between railway and EN2

There are some illegal inhabitants living between the railway adjacent to the site and EN2.
According to interviews with these inhabitants, they have been notified that they will be
relocated due to the construction of Maputo Ring Road, of which details are mentioned in
Chapter 8.2.3.

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(2) Accessibility
(a) Accessibility from Port Maputo
The site is located about 3 km from Port Maputo. As shown in Figure 3.3-1, major trunk roads
(EN1 & 2) can be used for the transportation of heavy equipment from Port Maputo to the site.

(b) Accessibility from the front road

As shown in Figure 3.3-3, there is an existing access road from EN2 leading to the site.
Therefore, the construction of new access road to the site is not required.
(c) Maputo Ring Road
If Maputo Ring Road is constructed prior to the construction of the new power plant, the
conditions of access to the site mentioned above will change. Therefore, the progress of the
planning and construction of Maputo Ring Road should be carefully monitored.

(Source: JICA Study Team)

Figure 3.3-3 Access from the Front Road at CTM Site

3.4 Topography, Geology and Meteorology

An outline of the topographical, geological and meteorological conditions of both the Beluluane and
CTM sites are summarized in Table 3.4-1. As described in the table, both sites have no significant
issues from the viewpoint of topography, geology and meteorology. For details of meteorological
conditions of the CTM site, please refer to Chapter 5.

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Table 3.4-1 Topographical, Geological and Meteorological Conditions of the Two Candidate
Sites
Item CTM Site Beluluane Site
Topography and The site is situated on alluvial soil The site is situated on diluvial upland at
geology deposited at the river mouth. Hard clay approximately 30 m above M.S.L. Since the
(N-value >50) is approximately 10 site is located on flat land, large-scale grading
meters below the ground level. work is not required. Although information
Accordingly, it is recommended to about geological conditions of the site is not
adopt the pile foundation for heavy available, it can be inferred that there are no
machinery and structures. significant problems in foundation design. In
fact, an aluminum smelter and cement
factories, which use heavy machinery
supported by strong foundations, are located in
the Beluluane Industrial Park.
Meteorology There is no risk of flood or storm surge There is no risk of flood damage.
damage. However, a proper drainage
system would be newly established
within the CTM in order to avoid water
inundation.
(Source: JICA Study Team)

3.5 Constraints of a Power System

3.5.1 Three Elements of Constraints

Three technical constraints, i.e., power flows, fault currents, and stability, must be satisfied for
the stable operation of a power system and the system must be analyzed in order to make this
judgment. Power flow analysis has been conducted to ascertain whether the facilities, such as
the transmission line and transformer, would not be overloaded and whether the proper value of
voltage could be maintained.

The power system facility cannot avoid faults such as short-circuiting. Should a fault occur, the
facility must be isolated from the system by a breaker. Fault current analysis must be carried out
to check if the fault current is lower than the rated breaking current of the breaker and thus the
breaker could break the fault current without any problems.

If a fault has occurred in the system and after the faulty facility has been isolated from the
system, the system must be able to continue the stable operation as prior to the occurrence of the
fault. Stability analysis must be performed to confirm whether any disturbances after the
occurrence of the fault have settled down as time passes and whether the system can return to
stable status.

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3.5.2 Target System

The current published future demand for power is forecast in the CESUL project, however
EDM is currently executing a Master Plan study to be completed at the end of 2012. EDM
provided the JICA Study Team with the network analysis data that it is using to develop the
plan. The JICA Study Team has also conducted network analysis of the power system in EDM’s
current network expansion plan.

Concretely, the following two cases of demand and system configuration, which are
prerequisites for analyzing the power system, are assumed:
 Base case: Demand is assumed as the forecast value of the CESUL project, and the existing
system will not be reinforced and will remains as it is in 2011 until the new southern gas-fired
power station is completed

 Reference case: Work data of demand and network configuration as of October 2012 from
EDM’s current network expansion plan are used

3.5.3 Base Case

(1) Forecast Demand

Values forecast in the CESUL project, which are the newest published data, are used.

Table 3.5-1 shows the expected growth of demand for the Southern system in the case where
demand grows moderately. Since the Southern gas-fired power station is expected to start
operation in 2017, that year is used as the subject of network analysis, and the expected demand
in that year is 653 MW as the average growth rate from 2015 to 2020 is expected to be 7.9%.

Table 3.5-1 Forecast Demand of the CESUL Project

Year Demand (MW) Growth rate (%)
2010 344
2015 575 10.8
2020 791 6.6
2025 995 4.7
2030 1213 4.0
2010 - 2030 6.5

(Source: Final Feasibility Study Report Mozambique Regional Transmission Backbone Project)

(2) Network System to be Connected to the Southern Gas-fired Power Plant

It is assumed, as described above, that the network configuration of 2011 will be maintained in
2017 when the power plant will begin operation. Figure 3.5-1 shows the network system of
2011 including the Beluluane and CTM substations, which are the related substations for the

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candidate sites. Both the sites use the 66 kV system that is supplied from the 275/66 kV Matola
and Infulene substations.

The Beluluane substation is 32 km away from the Matola substation, connected by one circuit of
transmission line with a transmitting capacity of 36 to 47 MW. From the Infulene transformer
station, the Beluluane substation is located 28 km away and is connected by one circuit of
transmission line with a transmitting capacity of 36 MW.

By contrast, the CTM substation is 5 km away from the Matola substation and connected with
three circuits of transmission lines with a transmission capacity of 47 to 57 MW, and 8 km away
from the Infulene substation and connected with three circuits of transmission lines of 36 to 47
MW. It is also connected to two circuits of 66 kV transmission lines that supply load. This
means that the CTM substation is connected with as many as eight circuits of transmission lines
and is closer to the 275 kV substation that is the source of supply. This gives an advantage in
terms of power transmission to the CTM site over the Beluluane site.

Legend Lindela

400kV AC
275kV AC Lionde
132kV AC
110kV AC Corumana
Komatiport Macia Xai-Xai
66kV AC
South Africa
Power station
Matola
Substation Gare Manhica Laulane

Amot Infulene
South Africa
Maputo Machava P.Canico
SE6
SE4

Mozal
Matola SE5
Beluluane SE7
Edwaleni
Swaziland
P.Mozal CTM
Matola SE2
Rio
SE1
Cimentos SE3

Boane

Salamanga

(Source: JICA Study Team)

Figure 3.5-1 Network System of the Southern Gas-Fired Power Plant

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(3) Installable capacity of power plant

Power is transmitted to the existing Beluluane substation from the 66 kV Matola Gare-Boane
line via a T-shape branching line. If a fault occurs anywhere along the total of 26 km
transmission line and the 24 km Matola Gare-Boane line or the 2 km T-shape branching line,
therefore, a blackout occurs. The role of the existing Beluluane substation is to supply power to
medium to small-size factories and it seems that this level of supply reliability is considered
sufficient. If a new power plant is constructed, however, it will be regarded as an important
power source for the Southern system and improving its reliability is of vital importance. It is
therefore assumed that one circuit of branch transmission line of 2 km will be newly installed as
shown in Figure 3.5-2, so that the branch section will consist of two circuits, changing the
branch method to a π-shape branching. By changing the branching method in this way, the
section that will be affected by any fault can be halved and, even if a fault occurs on one of the
transmission lines, power can still be transmitted by the healthy transmission line.

Matola
Gare Matola
Gare
14km

Beluluane
Beluluane
2km

10km
New plant

Boane
Boane

T-Branching π-Branching
(Source: JICA Study Team)

Figure 3.5-2 Interconnected Power System at Beluluane

It is necessary to assume output of the power plant in order to analyze the power system. The
Southern gas-fired power plant will be required to generate as much power as possible because
the power plant is expected to serve as the main power supply source from 2015 and onward.
Therefore, the output of the Beluluane and CTM sites is assumed as follows.
Firstly consideration is given to the capacity of the generator that can be installed on the
Beluluane site on the assumption that the branch method will be changed. The transmitting
capacity from Beluluane to Matola Gare and Boane is 36 MW in both directions. Even if it is

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assumed that the transmission lines in both directions are healthy and power generated by the
generator flows equally in both directions, the capacity of the generator that can be installed is
the sum of the total transmitting capacity of 72 MW in both directions plus the Beluluane
substation load (i.e., 5 MW according to the records of 2011). The actual power flow in the
transmission lines is unequal because power flow is determined by the load distribution and
power distribution of the total system. In addition, considering that the remaining healthy
transmission lines are used to transmit power in the case of any transmission line faults, it is
assumed that the capacity of the generator that can be installed at the Beluluane site is 50 MW.
On the other hand, the capacity of the generator that can be installed at the CTM site is assumed
to be 100 MW because this site is connected to a total of eight circuits with transmission
capacity of 36 to 57 MW.
(4) Power Flow Analysis Results

Figure 3.5-3 shows the results of the power flow analysis and Table 3.5-2 shows the main
overloaded transmission lines. The pink lines in this figure indicate overloaded transmission
lines. Even though demand has increased to about 1.7 times that of 2011, the system has not
been reinforced and there are as many as 15 overloaded transmission lines in the case of the
Southern gas-fired power plant.
In the case that a 50 MW plant is developed in Beluluane, the overload of the Infulene-Matola
Gare line and Matola-Matola Rio line can be eliminated and the number of overloaded lines can
be decreased to 13. However, the effect is limited only to the Beluluane neighborhood.
In the case that a 100 MW plant is developed at the CTM site, the overload of seven
transmission lines around CTM can be solved and the overloaded lines can be decreased in
number to eight. This is effective for eliminating the overload to some extent but cannot be a
fundamental solution to the problem. Overloading occurs on load supply lines such as the
CTM-SE2 and CTM-SE3 lines and is attributable to increasing demand. Moreover, after
installing 100MW CCGT, overloading caused by generator stoppage due to periodic inspection
or sudden stoppages by faulty occurrence should be considered. These indicate the necessity of
drastic measures for reinforcing the transmission lines.

Table 3.5-2 Main Overloaded Transmission Lines

Power Flow (MW) Red: Overload
Voltage Capacity
Line Without Power
(kV) (MW) Beluluane 50 MW CTM 100 MW
Plant
Maputo－Matola 275 455 634 584 535
Infulene－Matola Gare 66 36 38 12 36
Matola－Matola Rio 66 47 68 44 70
Matola－Machava 66 47 62 71 46
Matola－CTM 66 161 177 172 133
CTM－SE2 66 47 57 57 59
CTM－SE3 66 47 51 51 53

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Power Flow (MW) Red: Overload

Voltage Capacity
Line Without Power
(kV) (MW) Beluluane 50 MW CTM 100 MW
Plant
Infulene－SE7 66 36 42 43 31
Infulene－SE6 66 36 64 64 65
SE6－SE4 66 36 39 39 40
(Source: Network analysis results from the JICA Study Team using data provided by EDM）

Power plant not developed Matola Infulene

Gare
30
38
6
17
297 41
59
634
Machava 45
42 SE6
25
SE4
64 26
62 39 12
Maputo 30
11 34
177 30 37
Matola 10 6 18 SE5
Beluluane SE7
81
CTM
7 68 51 4
24
27 57
24
1 40
Matola Legend 33
Rio SE2 39
275kV AC
66kV AC SE3
Overloaded
Boane 24
Unit : MW

Matola
Infulene
Gare
50 MW power plant at Beluluane 30
12

26
268 43
59

Machava 45
43 SE6
584
25
SE4
64 26
19 71 39 12
Maputo 30
12
Beluluane 172
34
312 30 37
Matola 12 5 18 SE5
7 50 SE7
81
CTM
44 51 4
2.5

27 57
22 24
17 49
Matola 33 49
Rio SE2 39
SE1
SE3

Boane 24

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100 MW power plant at CTM Matola

Infulene
Gare
30
36
4
1
257 26
42
535 26 SE6
Machava 45
25
851 SE4
65 26
46 40 13
31
Maputo
5 34
133 31 37
Matola 6 24 23 SE5
7 SE7
81
Beluluane 70
24 53 1
8
8
5 100
27 59
17 24
3 41
Matola P.Mozal CTM 49
35 49
Rio 17 SE2 39
SE1
Cimentos SE3

Boane 24

(Source: Network analysis results from the JICA Study Team using data provided by EDM）

Figure 3.5-3 Power Flow Analysis Results (2017)

(5) Fault Current Analysis Results

Table 3.5-3 and Figure 3.5-4 show the results of analyzing fault currents. The maximum fault
current of the 275 kV bus is sufficiently low at 9.4 kA in Maputo if a 100 MW power plant is
installed at the CTM site, indicating that there are no problems such as an excess of the break
current. The maximum fault current of the 66 kV bus is at 17.0 kA in Infulene substation and
lower than 25 kA of the breaking capacity of the breaker if a 100 MW plant is installed at the
CTM site, indicating there are no problems.
A change in the fault current when a power plant is installed is a 2.0 kA increase from 4.3 kA to
6.3 kA at the 66 kV bus in Beluluane in the case of a 50 MW power plant development at
Beluluane, and a 3.4 kA increase from 13.2 kA to 16.6 kA at the 66 kV bus in CTM in the case
of a 100 MW power plant development at CTM. In either of the above cases, there will be no
excess breaking capacity caused by the installation of the power plant.

Table 3.5-3 Fault Currents at the Main Substation

Fault Current (kA)
Voltage
Station Without Power
(kV) Beluluane 50 MW CTM 100 MW
Plant
Maputo 275 8.9 9.1 9.4
Matola 275 7.6 7.8 8.2
66 12.1 13.2 12.9 13.6 13.0 15.8
Infulene 275 6.7 7.0 7.3
66 14.6 6.8 15.1 7.6 17.0 7.1
Beluluane 66 4.3 6.3 4.5
CTM 66 13.2 13.6 16.6

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Fault Current (kA)

Voltage
Station Without Power
(kV) Beluluane 50 MW CTM 100 MW
Plant
SE3 66 9.8 10.1 11.6
SE7 66 10.4 10.7 12.1
(Source: Analysis results using PSSE network data provided by EDM)

Matola
Power plant not developed Gare
4.6 6.7
3.9
14.6, 6.8
Infulene

Maputo Machava 11.2 SE6

10.0 10.9
SE4
8.9
18.8 9.6
19.5

Beluluane Mozal 7.6 10.1

10.4
Legend Matola 12.1, 13.2 SE5
4.3 SE7
400kV AC 13.2

275kV AC CTM
132kV AC 5.9 9.6
9.9
110kV AC
Matola P.Mozal
66kV AC Rio 8.9 SE2 9.8
Power station Cimentos SE3
Substation
Boane 4.6
Unit : kA

50 MW power plant at Beluluane Matola

Gare 7.0
5.9
4.1
15.1, 7.6
Infulene

Maputo Machava 11.7 SE6

10.2 11.2
SE4
9.1
19.0 9.8
19.8

Beluluane Mozal 7.8 10.4

10.7
6.3 Matola 12.9, 13.6 SE5
(4.3) SE7
13.6
( ):without generator
CTM
6.7
10.1
Matola
Rio SE2 10.1
SE1
SE3

Boane 5.7

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100 MW power plant at CTM Matola

Gare 7.3
4.7
4.1
17.0, 7.1
Infulene

Maputo Machava 12.0 SE6

10.4 12.8
SE4
9.4
19.2 11.0
20.0

Beluluane Mozal 8.2 11.6

12.1
4.5
Matola 13.0, 15.8 SE5
SE7
16.6
(13.2)
CTM
6.1
11.7
Matola P.Mozal ( ):without generator
Rio SE2 11.6

SE3

Boane 4.7

(Source: Network analysis results from the JICA Study Team using data provided by EDM）

Figure 3.5-4 Fault Current Analysis Results (2017)

(6) Stability Analysis Results

Transmission lines are subject to faults from lightning and contact with trees. After the faulted
line is isolated from the system by opening a breaker, the disturbance of the fault must settle
down and the system must be able to return to the original stable condition. For stability
analysis, it was assumed that the fault occurred at the closest to the power plant, where fault
conditions for stability are severe, ignoring control systems such as the automatic voltage
regulator (“AVR”) and governor control unit (“GOV”), in order to assess stability inherent in
the system. In addition, it was assumed that the fault clearing time of the 66 kV transmission
line was 0.1 to 0.15 seconds from the records of EDM shown below.

Distance from bus to fault point:

0 to 80% of transmission line length Zone 1: 0.1s
Greater than 80% of transmission line length Zone 2: 0.1 to 0.4s

Table 3.5 4 shows the results of stability analysis and Figure 3.5-5 shows the fluctuation curve
of the generator voltage angle. In the case where a 50 MW power plant is installed at the
Beluluane site, the network will be stable if the fault clearing time is 0.1 second. If the clearing
time is 0.15 seconds and in the case where a fault occurs at the Beluluane end of the
Beluluane-Boane line (Case 2), fluctuation of the generator voltage angle diverges, and the
system cannot be kept stable. This is because the Beluluane-Boane line will be opened after the
fault and thus there is no choice but to transmit power with one circuit of the Beluluane-Matola
Gare line.

Conversely, in the case where a 100 MW power plant is installed at the CTM site, fluctuation

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

converges in all fault cases even if the fault clearing time is 0.15 seconds. This is because a total
of eight circuits of transmission lines – three circuits to Matola substation, three circuits to
Infulene substation, and two circuits to SE3 substation – are connected to CTM, therefore, even
if one circuit of transmission line is opened due to a fault, connection to the main system is
ensured by the remaining seven circuits. This is substantiated by the fact that the fluctuation
amplitude after the fault is smaller than that at the Beluluane site.

Table 3.5-4 Stability Analysis Results

Fault Clearing
Plant Faulted Line Fault Point Stability Case No.
Time
0.1 sec Stable 1
Beluluane Beluluane-Boane
Beluluane 0.15 sec Unstable 2
50 MW
Beluluane-Matola Gare 0.15 sec Stable 3
CTM-Matola 0.15 sec Stable 4
CTM 100 CTM-SE2 0.15 sec Stable 5
CTM
MW CTM-SE3 0.15 sec Stable 6
CTM-SE6 0.15 sec Stable 7
(Source: Network analysis results from the JICA Study Team using data provided by EDM)
Beluluane 50MW development

Case 1 Case 2 Case 3

CTM 100MW development

Case 4 Case 5 Case 6 Case 7

(Source: Network analysis results from the JICA Study Team using data provided by EDM)

Figure 3.5-5 Fluctuation Curve of Generator Voltage Angle

(7) Conclusion

Table 3.5-5 provides the results of the network analysis. Installable generator capacity is limited
to 50 MW at the Beluluane site due to constraints of the transmitting capacity, whereas
approximately 100 MW can be installed at the CTM site. While there are two transmission lines

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

that are set free from overload by installation of a generator at the Beluluane site, there are
seven circuits if a generator is installed at the CTM site. The fault current after installation of a
generator is sufficiently smaller than the current breaking capacity of the breakers, and there is
no problem in both cases.
In the case of installation of a generator at the Beluluane site and if a fault occurs on the
Beluluane-Boane line and is cleared 0.15 seconds later, the network is deemed unstable. By
contrast, in the case where a generator is installed at the CTM site, the network is stable in all
fault cases. It can be judged from the above that installing a generator at the CTM site is
advantageous over the installation at the Beluluane site.
Moreover, in the case that the CCGT plant is developed at the CTM site, a generator of 110
MW capacity can be developed for the following reasons:
1) increase of generator capacity does not encourage overloading of transmission lines because
overloading is caused in supply lines,
2) fault currents are much lower than permissible value, and
3) no small margin for stability limits seems to exist because the fluctuation curve of the
generator voltage angle converges well.

Table 3.5-5 Results of the Network Analysis

Beluluane CTM
Installable capacity Max. of 50 MW Approx. 100 MW
Improvement of overload problem 2 lines 7 lines
Much lower than CB
Fault current Much lower than CB rating
rating
Stability Depends on fault clearing time Stable
Overall evaluation － Advantageous
(Source: JICA Study Team)

3.5.4 Reference Case (Based on EDM’s Current Network Expansion Plan)

EDM is currently making a network expansion plan to be completed at the end of 2012, and in
October 2012 the JICA Study Team obtained the network analysis data reflecting the current
network expansion plan, as this data can be used as reference for studying methods to connect
the Southern gas-fired power plant. The JICA Study Team analyzed the network system based
on this data. As the obtained data is still in draft version, it is possible that the final version may
have different content.

(1) Network Configuration

The Southern gas-fired power plant is expected to start operation in 2016 or 2017. EDM’s
current network expansion plan predicts that power demand will substantially increase in the

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

future, to 794 MW in 2016, which is greater than the value of 653 MW for 2017 estimated by
the CESUL project, described in (1) of 3.5.3. Therefore, the system for 2016 was selected as the
subject analysis reflecting EDM’s current network expansion plan.
Figure 3.5-6 shows the 2016 system of EDM’s current network expansion plan. According to
the plan, a 275 kV Matola-CTM line using the transmission route of the existing 66 kV
Matola-CTM line and a 275 kV Infulene-CTM line will be installed. A 275 kV system leading
to the CTM substation will be introduced to the demand center area, and new 275 kV
transmission lines that go around Maputo City from CTM via a new Facim substation and SE5
substation, that will be upgraded from the existing 66 kV to 275 kV, will be introduced.
Moreover, a new 275 kV transmission line that goes from the existing 400/275/132 kV Maputo
substation to the Infulene substation will be installed. As a result, overloading of the 66 kV
transmission lines can be eliminated and reliability of supply to the capital city can be expected
to improve.
Legend
Lindela
400kV AC
275kV AC Chongoene
Magude Lionde
132kV AC
110kV AC
66kV AC Komatiport
South Africa R Garcia Corumana
Power station Xai-Xai
Macia
Xinavane
Substation
Riopele
Matola
Gare Manhica Laulane
Amot
South Africa Infulene
SCMAPARN

Machava SE8

Maputo SE6
SE4
91361
Mozal 91371 SE5
Matola
90961 SE7
SCMAPSEB 90962
Beluluane 90991
90992
SEB400
CTM SE1
Matola P.Mozal
Rio SE2
Cimentos SE3
Edwaleni
Swaziland Boane
Facim
Salamanga

(Source: Diagram drawn by the JICA Study Team based on EDM’s current network expansion plan
provided by EDM)

Figure 3.5-6 System of EDM’s Current Network Expansion Plan (2016)

(2) Power Flow Analysis Results

Table 3.5-6 and Figure 3.5-7 show the results of power flow analysis before and after the start
of operation of the 100 MW plant of CTM under the system of EDM’s current network
expansion plan (2016). Before the 275 kV transmission line is reinforced, fifteen lines are
overloaded. Overloading of the transmission line around CTM will be solved by introducing a
275 kV transmission line to the capital city and the number of overloaded lines will decrease to
three: the Matola-Matola Rio line, Infulene-Matola Gare line and SE5-SE8 line.

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

The main function of all these overloaded transmission lines is to supply power to regional
loads which have become overloaded as regional loads increase. Measures, such as circuit
additions, will have to be taken as these overloaded transmission lines will not receive the
benefits of the introduction of a 275 kV transmission line to the capital city.

If a 100 MW plant is installed at CTM, the CTM-SE2 line will be newly overloaded. This is
because the power flow of this transmission line before installation of the plant is 43 MW
against the transmission capacity of 47 MW, which is a small margin, and because the power
flow increases in the directions of SE2, SE3, and SE7 as a result of the installation of the plant
at CTM.
As a countermeasure against this overloading and exceeding the permissible value of fault
current, which will be described later, the case in which the CTM-SE3, SE2-SE3, SE3-SE7,
SE4-SE6, and Infulene-SE7 lines are always open and each 66 kV network is operated radially
in 275 kV substation units, is considered. This countermeasure solves the overloading of the
CTM-SE2 line.
However, overloading of the Matola-Matola Rio, Infulene-Matola Gare, and SE5-SE8 lines is
not solved. In addition, the Infulene-Laulane line is newly overloaded. The essential cause of
overloading of the 66 kV transmission lines is that the transmission line constructed in the early
years had a capacity as small as 36 MW, which was used without being reinforced.
Fundamental measures such as thickening conductors of the lines and circuit additions will be
needed in the future.

Table 3.5-6 Results of the Power Flow Analysis for EDM’s Current Network
Expansion Plan System (2016)
Power Flow (MW) Red: Overload
Voltage Capacity
Line Before CTM After CTM 100MW
(kV) (MW)
100 MW Closing Lines Opening Lines
Maputo－Matola 275 455 289 250 248
Matola－Infulene 275 455 10 2 6
Matola－CTM 275 >455 161 120 112
Infulene－CTM 275 >455 108 75 62
Infulene－Matola Gare 66 36 55 55 55
Matola－Matola Rio 66 47 58 58 58
CTM－SE2 66 47 43 53 43
CTM－SE3 66 47 27 39 -
Infulene－SE7 66 36 1 0 -
Infulene－SE6 66 36 26 25 26
Infulene－Laulane 66 36 35 35 38
SE5－SE8 66 36 42 43 39
(Source: Analysis results using PSSE network data provided by EDM)

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73
1 Infulene
245 R Garcia 3
174 7

Before power plant development Matola

Gare 55
21
Laulane
36 35
18 161
53
deundeveloped 264
164
10
10 26 18
3
Maputo 1 SE8
Machava 42
1
26
971 108 24
850 289 0
1404 SE6 29
39 42
850 SE4
29
433 91361
Mozal 160
91371 SE5
Matola 127
21
1
14 SE7
90961 CTM 87
Beluluane 58 161 90962
127
90991 27
31 90992 4
43 19
20 5
26 56 SE1
4 1
P.Mozal 43 4
37 Matola 50
Rio 26 SE2 68
143 57 54
Cimentos SE3
147
Boane 20 21
36
Overloaded line Facim
21 Salamanga

72
20 Infulene
After 100 MW development 245 R Garcia 3
153 7
Matola 21
at CTM Gare
36
55
159 35
Laulane
18
53
230
148
10
2 25 18
3
Maputo 0 SE8
Machava 42
0
26
936 75 24
850 250 1
1330 SE6 29
38 43
850 SE4
29
395 91361
Mozal 156
91371 SE5
Matola 127
21
4
14 SE7
90961 CTM 87
Beluluane 58 120 90962
54
90991 39
31 90992 8
56 53 26
20 5
26 100
SE1
4 9
P.Mozal 43 2
37 Matola 50
Rio 26 SE2 68
5 141 49 48
Cimentos SE3
133
Boane 20 21
36
Overloaded line Facim
21 Salamanga

72
20 Infulene
After 100 MW development 245 R Garcia 3
152 7
Matola 21
Gare 55 Laulane
at CTM and line opening 18
36
152 38
53
232
162
10
6 26 15
3
Maputo SE8
Machava 42
26
935 62 24
850 248
1330 SE6 29
38 39
850 SE4
29
395 91361
Mozal 177
91371 SE5
Matola 129
21
22
14 SE7
90961 CTM 87
Beluluane 58 112 90962
5
90991
31 90992 14
5 56 43
20 SE1
26 100
4
P.Mozal 43 6
37 Matola 50
Rio 26 SE2 68
5 169 62 56
Cimentos SE3
154
Boane 20 21
Overloaded line 36
Facim
21 Salamanga

(Source: Analysis results using PSSE network data provided by EDM)

Figure 3.5-7 Results of Power Flow Analysis using EDM’s Current Network
Expansion Plan System (2016)

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(3) Fault Current Analysis Results

Table 3.5-7 and Figure 3.5-8 show the results of fault current analysis using EDM’s current
network expansion plan system (2016). The fault current of the 66 kV bus will substantially
increase as a result of introducing the 275 kV system to the metropolitan area but its value will
not exceed the permissible value, i.e., 25 kA, although it will come close, before the 100 MW
plant at CTM starts operating. After the plant is up and running, however, the fault current will
increase 3.3 kA at CTM to 26.2 kA, exceeding the permissible value. It will also exceed the
permissible values in Facim, SE5, SE3, and SE7, and the maximum value will be 26.7 kA in
SE3.
The reason for exceeding the maximum value of 25 kA is that the 66 kV substations are closely
interconnected to each 275 kV substation through the 66 kV transmission lines. Before the 275
kV transmission line will be introduced to the metropolitan area, there is no choice but to use all
66 kV transmission lines in parallel because it will be necessary to supply power from Matola
and Infulene substations to the metropolitan area with transmission lines having small
transmitting capacity. After the 275 kV line is introduced to the metropolitan area, however, it
will transmit power to the metropolitan area and the 66 kV transmission line will change its role
to supplying power regionally to the 66 kV substations from 275 kV/66 kV substations of CTM,
Facim, and SE5. Consequently, the reliability of supply is not greatly influenced even if the 66
kV system is divided into plural systems by opening the 66kV transmission lines.
Therefore, the case in which the CTM-SE3, SE2-SE3, SE3-SE7, Infulene-SE7, and SE4-SE6
transmission lines are opened is considered as an example of a countermeasure against
overloading of the CTM-SE2 line. In this case, the maximum value of the fault current
significantly falls to 21.9 kA at the CTM and Infulene substations.

Table 3.5-7 Results of Fault Current Analysis using EDM’s Current Network Expansion
Plan System (2016)
Fault current (kA)
Voltage
Station Before CTM After CTM 100 MW
(kV)
100 MW Closing Lines Opening Lines
Maputo 275 9.7 10.4 10.3
Matola 275 8.9 9.6 9.6
66 20.3 21.2 20.5
Infulene 275 9.2 9.9 9.9
66 23.6 25.0 21.9
CTM 275 8.8 9.5 9.5
66 22.9 26.2 21.9
Facim 275 8.3 8.9 8.8
66 24.1 26.0 17.8
SE5 275 8.3 8.9 8.8
66 23.7 25.1 19.9
SE3 66 24.7 26.7 16.7

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Fault current (kA)

Voltage
Station Before CTM After CTM 100 MW
(kV)
100 MW Closing Lines Opening Lines
SE7 66 23.9 25.7 13.2
(Source: Analysis results using PSSE network data provided by EDM)

R Garcia
10.0

Matola
Before power plant development Gare
7.8
9.2
2.5
Laulane

23.6 14.6
Infulene
deundeveloped
Maputo SE8
Machava 19.9
16.1
10.8 15.3
9.7 SE6 16.3
20.2
21.0 SE4
8.3
91361
Mozal 8.9 91371
23.7 SE5
Matola 20.3
23.9
6.7 90961
CTM SE7
8.8
90962
Beluluane 90991
22.9
90992

8.5 14.3
SE1
P.Mozal 19.1
Matola 23.0
Rio 12.7 SE2 24.7

Cimentos SE3
8.3
Boane 6.5 24.1

Facim
1.0 Salamanga

After 100 MW development

in CTM

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 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

After 100 MW development

R Garcia
10.2
at CTM and line opening Matola
Gare 9.9 Laulane
7.8
2.5
21.9 14.4
Infulene

Maputo SE8
Machava 19.5
11.2
11.0 14.8
10.3 SE6 11.2
20.6
21.4 SE4
8.8
91361
Mozal 9.6 91371
19.9 SE5
Matola 20.5
13.2
6.7 90961
CTM SE7
9.5
90962
Beluluane 90991
21.9
90992

8.5 14.5
SE1
P.Mozal 11.8
Matola 16.7
Rio 12.9 SE2 16.7

Cimentos SE3
8.8
Boane 6.5 17.8

Facim
1.0 Salamanga

(Source: Analysis results using PSSE network data provided by EDM)

Figure 3.5-8 Results of Fault Current Analysis using EDM’s Current Network
Expansion Plan System (2016)

(4) Stability Analysis Results

The stability of the system that opens transmission lines, such as the CTM-SE3 and SE2-SE3
lines, as a countermeasure against the excess of permissible values of the fault current after a
100 MW plant is installed at CTM was analyzed. In regards to the control systems of the
generator, such as AVR and GOV, both the case where the control systems were ignored in
order to identify the stability inherent to the system and the case where they were considered
were analyzed. In addition, both fault clearing times of 0.1 second and 0.15 seconds were
considered.
Table3.5-8 shows the result of stability analysis. Figure 3.5-9 shows the fluctuation curve of the
generator voltage angle.
In the case where the control systems were ignored and the fault clearing time was 0.10 second,
the network was stable in all cases including the case where it was assumed that a fault occurred
on the CTM 275 kV bus or 66 kV bus, the closest end to the generator which is severe in terms
of stability. In the case where the fault clearing time was 0.15 seconds, however, the effect of
introducing the 275 kV transmission line to the metropolitan area could not be seen and the
network was unstable in all cases.
Comparing these results with the case described in (6) of 3.5.3 where the CTM power plant was
connected to the 66 kV system before the introduction of the 275 kV system and the network
was stable with the control systems ignored and fault clearing time being 0.15 seconds, it can be
said that introducing the 275 kV system will not be effective for improving stability. The reason
for this is considered as follows: Before the 275 kV system will be introduced, the CTM plant

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will be connected to eight circuits of 66-kV transmission lines. Even if one of the circuits will
be opened as a result of a fault, the generator will be kept connected to the main system by the
other seven circuits. After the 275 kV system will be introduced, however, the case where the
CTM-SE3 line will always be opened to suppress the fault current is assumed. After the
CTM-SE2 line will be opened to remove faulted lines, connection to all the 66 kV transmission
lines will be lost and the generator will be connected to the main system only by a 275/66 kV
transformer with high impedance.
In practice, the fault clearing time of the 275 kV transmission line will be 0.1 second or less,
shorter than that of the 66 kV transmission line, and it is expected that stability will be
maintained even if a fault occurs on the 275 kV transmission line.
In the case where the control systems of the generator are considered, stability will be
maintained in all cases where a fault on all the 275 kV and 66 kV transmission lines is assumed,
even if the fault clearing time is assumed to be 0.15 seconds. In general, a control system will be
installed for all generators, and it is considered that the network will not become unstable.

Table 3.5-8 Results of Stability Analysis under EDM’s Current Network Expansion Plan
System (2016)
Control Fault Clearing
Faulted Line Fault Point Stability Case No.
System Time
0.10 sec Stable 8
275 kV Matola-CTM
0.15 sec Unstable 9
0.10 sec Stable 10
275 kV Infulene-CTM CTM 275kV
0.15 sec Unstable 11
Ignored
0.10 sec Stable 12
275 kV CTM-Facim
0.15 sec Unstable 13
0.10 sec Stable 14
66 kV CTM-SE2 CTM 66kV
0.15 sec Unstable 15
275 kV Matola-CTM 0.15 sec Stable 16
275 kV Infulene-CTM CTM 275kV 0.15 sec Stable 17
Considered
275 kV CTM-Facim 0.15 sec Stable 18
66 kV CTM-SE6 CTM 66kV 0.15 sec Stable 19
(Source: Network analysis results from the JICA Study Team using data provided by EDM)

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Control System Ignored

Case 8 Case 9 Case 10 Case 11

Case 12 Case 13 Case 14 Case 15

Control System Considered

Case 16 Case 17 Case 18 Case 19

(Source: Network analysis results from the JICA Study Team using data provided by EDM)
Figure 3.5-9 The Fluctuation Curves of Generator Voltage Angles under EDM’s Current
Network Expansion Plan System (2016)

(5) Conclusion

Table 3.5-9 provides the analysis results under EDM’s current network expansion plan system.
The ascertained results by power flow analysis are as follows:
Overloading of many existing 66 kV transmission lines will be solved by introducing 275 kV
transmission lines to the metropolitan area but some overload will remain for some transmission
lines for regional supply to which the effects of introducing the 275 kV lines are not reached.
This is an intrinsic problem that rises as demand grows. To solve this problem, the conductors
of existing transmission lines need to be changed to thick ones or new transmission lines must
be installed.
The ascertained results by fault current analysis are as follows:
As a result of introducing the 275 kV transmission line, the fault currents of the 66 kV bus will
substantially increase, exceeding the maximum permissible value of 25 kA at five stations. As a
countermeasure against this, replacing the existing breaker with a new one having a high rated

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current breaking capacity may be a solution. However, it is recommended to open some 66 kV

transmission lines and divide the 66 kV system into plural systems. In this way, the power,
which flows into the 275 kV transmission line before any faults, can be prevented from shifting
into the 66 kV system and the 66 kV transmission lines can be prevented from being overloaded.
Usually, when a high voltage system and a low voltage system operate in parallel, power flow
before fault occurrence shifts to the low voltage system, overloading the low voltage system is
caused and the effects of a fault expands one after another. Dividing the 66 kV system in units
of 275/66 kV substations has the effect of limiting the range of the influence of a fault.
The ascertained results by stability analysis are as follows:
When the 275kV transmission line will be introduced and the 66 kV transmission line will be
opened, the connectivity of the generator installed on the CTM 66 kV bus with the 66 kV
system will drop. In the case where a 66kV transmission line fault occurs and the fault clearing
time is 0.15 seconds, inherent network stability that does not consider the control system of the
generator will become unstable. If the fault clearing time is 0.10 seconds, the network will be
stable. If the generator control system is taken into consideration, the network will be stable
even if the fault clearing time is 0.15 seconds and no problems of stability are considered to
arise in the actual system.

Table 3.5-9 Conclusion of Analysis Results under EDM’s Current Network

Expansion Plan System (2016)
Item Results
Power ・Number of overloaded existing lines will decrease because of introducing 275 kV lines
flow ・Some lines to mainly supply to local load will remain overloaded
・Fault currents will exceed permissible maximum value 25 kA at 66 kV bus in many
Fault stations
current ・In order to reduce fault currents, some of the 66kV lines should be opened continuously
to configure radial network
・Inherent stability without control system depends on fault clearing time (“FCT”),
Stability stability cannot be maintained at FCT 0.15s
・Stability with control system can be maintained
(Source: JICA Study Team)

3.6 Fuel Gas Volume Constraints

3.6.1 Fuel Gas Volume Constraints

Fuel gas supply is considered as a part of the natural gas distribution project to Maputo by Empresa
Nacional de Hidrocarbonetos de Mocambique (“ENH”, English name - Mozambican National
Hydrocarbon Company). Therefore, any construction cost for gas feeding to the CCGT Project is
basically out of the scope of the CCGT Project . Since natural gas supply volume is limited to 6
MGJ per year, the power output of the new CCGT is also limited to approximately 100 MW.

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3.6.2 Gas Supply Contract Constraints

The CTM can be fed by a gas substation to be built by ENH at the site of the CTM, while at the
Beluluane site it may be required to build a dedicated 3.5 km pipeline. This requires further
agreements with the concession holders like Matora Gas Company that may delay the project
implementation.

Gas incoming

Gas Station

(Source: JICA Study Team)

Figure 3.6-1 Location of Gas Station and Gas Pipeline Route

3.6.3 Constraints for Environmental and Social Consideration

The Environmental Impact Assessment (“EIA”) for the gas pipeline construction works from PRS-2
to CTM and Maputo City have already been approved by the government. In the meantime, in the
case of the Beluluane site, it is necessary to newly install a gas pipeline from PRS-2 to the Beluluane
site and a concession agreement with Matola Gas Company, etc., may be required and thus another
EIA for this work may also be required. Therefore, it is anticipated that it would take a longer time
to construct a power plant at the Beluluane site. Getting approval for the EIA and making a
concession agreement would likely cause a delay of construction of the power plant at Beluluane.

3.7 Potential CCGT Product

According to the sections on “Development area and general layout”, “Fuel gas volume
constraints” and “Transmission constraints,” one block multi-shaft 1-on-1 CCGT, with capacity

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of Maximum 50 MW can be installed at the Beluluane site and one block of multi-shaft 2-on-1
110 MW CCGT can be installed at the CTM site. Applicable CCGT models for each site are
shown Tables 3.7-1 and 3.7-2 from the 2012 GTW Handbook. At the CTM site, a GGCT model
can be selected from many manufactures. However, at the Beluluane site, only a few applicable
CCGT models can be selected.

Table 3.7-1 Major Combined Cycle Power Generation Plants for Beluluane (GT
One-shaft Configuration)

Efficiency (%]
Manufacturer Model Output (MW)
(LHV)
GE 106F 118.4 55.0
Siemens SCC800 66.1 53.7
GE 106B 64.8 50.4
IHI (GE licensee) LM6000PD 55.2 53.3
Hitachi 1025(H-25) 43.8 50.1
Rolls-Royce RB211-GT61 42.6 52.8
(Source: JICA Study Team)

Table 3.7-2 Major Combined Cycle Power Generation Plants for CTM
(GT One-shaft Configuration)

Manufacturer Model Output (MW) Efficiency (%) (LHV)

GE 206B 130.9 50.9
IHI (GE licensee) 2 x LM6000PD 111.0 53.6
Hitachi 2025(2 x H-25) 87.8 50.3
Rolls-Royce 2 x RB211-GT61 85.3 52.8
Pratt &Whitney SWIFTPAC60 74.2 51.3
Siemens SCC600 73.4 50.9
(Source: JICA Study Team)

3.8 Comparison of the Candidate Sites

In selecting a power plant construction site, the necessary layout of the site area, present
situation, accessibility, topography, geology, and weather conditions of the site, constraints of
the system, fuel supply constraints, condenser cooling method, and selectivity of CCGT
equipment were objectively and comprehensively compared and studied, based on the items of
assessment stated above.

The results of the comparison and study of the two power plant construction sites are shown in

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Table 3.8-1. The CTM site was selected as the project site for a power plant up to 100 MW. The
major determining factor was transmission network capacity constraint. The results of the
comparison and study of the two power plant construction sites are shown below.

Table 3.8-1 Comparison of the Candidate Sites

CTM Beluluane

Development area and 3.7ha 1.5ha

general layout -> 110 MW X 2 units -> 110 MW X 1 unit
Land preparation and Easy land clearance and access Easy land clearance
accessibility and access
Topographical, geological, Special care required for potential floods Moderate condition
and meteorological by heavy rain
conditions -> 0.5-1m high embanking
Transmission line constraints Relatively higher capacity Lower capacity
approx. 100 MW at max. 50 MW

Fuel gas volume constraints 6.0 MGJ/yr 6.0 MGJ/yr

-> up to 110 MW -> up to 110 MW
Steam turbine condenser Easy access to sufficient water resources Insufficient water
cooling -> 3 types (Once-through, Wet Cooling resources
Tower, Air Cooled Condenser) -> Only Air Cooled
Condenser
Potential CCGT products For 70-110 MW For 50MW
-> Wide selection -> Few options
Conclusion Up to 110 MW CCGT with Up to 50 MW CCGT
Once-through, Wet Cooling Tower, or Air with Air Cooled
Cooled Condenser Condenser
(Source: JICA Study Team)

3.9 Output from Workshop for Site Selection

Based on the above results of the study of site selection, a workshop was held (October 4, 2012)
to officially decide the development point of EDM, with Mr. Adriano Jonas (in charge of
generation, transmission/distribution, and sales), a board member of EDM, participating. In this
workshop, the CTM site was officially decided as the development point and conditions for
basic design were determined.

(1) Mojor specifications

 Rated generation capacity: 70 to 110 MW
 Thermal efficiency: More than 50%
 Capacity factor: More than 80% (for base power supply)
 Fuel: Natural gas from Pande gas field

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(2) Major equipment

 Combined Cycle Gas Turbine (“CCGT”) plant
a. GT and generator: 2 units
b. ST and generator: 1 unit
c. Heat recovery steam generator: 2 units
d. Air cooled condenser: 1 unit
e. Auxiliary facilities such as 11 kV switch gear, step-up transformer, fuel gas supply
facility, water supply tank , etc.
 Civil works such as foundation piling, buildings
 Other facilities for water treatment, wastewater treatment, and fire fighting

(3) Other
The location of the CCGT power plant at CTM requires environmental approval from MICOA.
Prior to the approval, an application for determining the category of a social EIA must be filed.
In accordance with the intentions of EDM to promptly advance these administrative procedures,
the basic specifications of the CCGT power plant were assumed as follows and local
applications were moved forward in parallel and simultaneously.
 Generated electricity is delivered to mainly Maputo City via the existing CTM 66 kV
substation ajacent to the CTM power station.
 The monitoring and control system will be integrated into the exisiting Supervisory Control
and Data Aquisition (“SCADA”) at the Southern region load dispatch center adjacent to the
power station.
 The power plant is expected to start construction in 2014 and be put into commercial
operation in 2017 using Japan’s Offical Development Assistance (“ODA”) financial
source.
 The power plant is expected to achieve a lower production cost of approximately 0.07 –
0.08 USD/kWh, and its construction cost on EPC contact basis is estimated to be
approximately USD 120 million in consideration of international practices so far.

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 Chapter 4

Suitable rated power and General Specification

 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Chapter 4 Suitable Rated Power and General Specification

4.1 Suitable Rated Power

4.1.1 Fuel Gas Supply Amount

As stated in the already concluded electric power sector investigation results, the new gas-fired
power plant is assumed to have base load operation with 100% load and high capacity factor
because of continuous operation, except for planned outages for periodic inspections and facility
maintenance.

CCGT capacity is restricted by the amount of fuel natural gas that will be supplied. Since the
gas supply amount to the new gas-fired power plant is 6.0 MGJ/year, the power plant capacity is
calculated at approximately 114 MW.

The available generation capacity (MW) = 6.0 x 106 x 109 x (50/100) /(24 x 365 x (83/100) x 3.6
x109)
where the plant thermal efficiency and capacity factor are assumed to be 50% and 83%,
respectively.

4.1.2 Power Plant Area

The power plant capacity is also restricted by the scale of the plant to be installed at the planned
site. For the CTM Maputo thermal power station, a new power plant candidate, a total of about
3.7 ha (i.e., the former coal-fired thermal power plant area plus the diesel oil tank area for
existing gas turbines) will be needed for the new power plant. As described in Section 3.2, two
blocks of 110 MW class 2-on-1 type CCGT can be installed in the CTM Maputo power station.

4.1.3 Gas Turbine Manufacturer

The CCGT rated capacity is determined by the gas turbine (“GT”) and steam turbine. The GT
output is determined by the type of the GT manufacturer, i.e., not arbitrarily decided by the user.
Normally, the EPC contractor selects a GT suitable for the output and shaft configuration of the
power plant from the manufacturer’s GT models and combines it with a steam turbine suitable
for the steam condition and steam amount generated in the Heat Recovery Steam Generator
(“HRSG”).

Table 4.1-1 shows applicable CCGTs which can support the power generating possible output of
114 MW calculated from the gas supply amount in the CCGT with the multi-shaft 2-on-1 CCGT
in the order from larger output. Each CCGT output and efficiency is from under ISO conditions
(i.e., 15C, humidity 60%, 1013hPa).

Table 4.1-1 Applicable major CCGT model

Manufacturer Model Output (MW) Efficiency (%] (LHV)
IHI (GE licensee) 2xLM6000PD 111.0 53.6
Hitachi 2025(2 x H-25) 87.8 50.3
Rolls-Royce 2 x RB211-GT61 85.3 52.8
Siemens SCC-700 2x1 83.6 52.5
Pratt &Whitney SWIFTPAC60 74.2 51.3
(Source: 2012 GTW Handbook)

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For CCGT rated capacity, the CCGT range for selection can be expanded by making a setting
with a margin of 70-110 MW and the promotion of proper and active competition bidding
among EPC contractors.

4.2 Power Block Configuration (2-on-1, 1-on-1)

4.2.1 CCGT Configuration

The CCGT configurations with the rated capacity of 70-110 MW consisting of one or two gas
turbines and Heat Recovery Steam Generator (HRSG), and one steam turbine are evaluated. The
CCGT configurations to be evaluated will consist of two gas turbines and HRSGs, for the
following reasons:
(1) One 70-110 MW class CCGT consisting of one gas turbine, one HRSG and one steam
turbine is impossible to operate continuously during planned outages of GT periodical
inspections, maintenance and forced outages by GT breakdown in which the GT has higher
breakdown risk than the main facility.
(2) Fair competitive bidding is not likely because of the limited amount of applicable CCPP
manufacturers, i.e., GE and Ansaldo, and the EPC cost is higher.

There are two types of CCGT configurations: one-shaft configurations and multi-shaft
configurations. One-shaft configurations connect the GT, steam turbine, and the power
generator on the common shaft. If the common shaft is not shared by the GT and compressor, a
one-shaft configuration cannot be used.

In Japan, nuclear power plants operate 100% load as the base load of power demand, and
thermal power stations operate for middle and peak loads for changing electric power demand.
For one-shaft configurations it is possible to quickly stop and start high thermal efficiency at
plant partial loads, therefore one-shaft configurations are adopted in great quantities in Japan.
Multi-shaft configurations use different shafts for the GT generator and for the steam turbine
generator. They are used in the world in great quantities.

In addition, multi-shaft configurations include 1-on-1 types having one block of one GT
generator, HRSG, and one steam turbine generator and 2-on-1 type including two GT generators,
two HRSGs, and one steam turbine generator.

Table 4.2-1 shows shaft configuration.

Table 4.2-1 Type of CCGT configuration

Type A Type B Type C

Multi-shaft Multi-shaft One-shaft

Configuration 2GT + 2HRSG and 1ST 1GT + 1HRSG and 1ST 1GT + 1HRSG + 1ST
(2-on-1) (1-on-1)

(Source: JICA Study Team)

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Fuel
Gas Stack
Generator
Turbine
Heat Recovery Steam
Compressor Generator
Air Pump

Steam Turbine
Generator Gas Stack
Generator
Turbine
Heat Recovery Steam
Generator
Condenser Air Pump

Type A: Multi-shaft CCGT (2-on-1)

Steam Turbine Fuel

Gas Stack
Generator Generator Turbine
Heat Recovery Steam
Compressor Generator
Condenser Air Pump

Type B: Multi-shaft CCGT (1-on-1)

Steam Turbine Fuel

Compressor Gas Stack
Generator
Turbine
Heat Recovery Steam
Generator
Condenser Air Pump

(Source: JICA Study Team)

Type C: One-shaft CCGT

Figure 4.2-1 Type of CCGT configuration

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4.2.2 Main Characteristics of CCGT Shaft Configurations

(1) Output and Thermal Efficiency

Two blocks of multi-shaft type 1-on-1 or one-shaft type CCGT use two small-capacity steam
turbines but multi-shaft type 2-on-1 use one large-capacity steam turbine, i.e., a small loss of
steam. If capacity is increased, the output and efficiency of the entire plant will become higher
than the other two types. For CCGT efficiency, GT efficiency suddenly drops at about 80% of
the rated output. For partial loads of the plant, since high-load operation can be done in each
block in multi-shaft 1-on-1 and one-shaft CCGT, they have higher efficiency than multi-shaft
2-on-1 in partial load operation.

The following compares the output and efficiency between one block of multi-shaft type 2-on-1
CCGT and two blocks of multi-shaft 1-on-1 type and one-shaft type CCGT.

Table 4.2-2 Comparison of performance of CCGT configuration

Multi-shaft 2-on-1 x 1 Multi-shaft 1-on-1 x 1

Manufacture Model Efficiency (%) Efficiency (%)

Output (MW) Output (MW)
(LHV) (LHV)

IHI (GE Licensee) 2 x LM6000PD 111.0 53.6 110.4 53.3

Hitachi 2025 (2 x H-25) 87.8 50.3 87.4 50.1
Rolls-Royce 2 x RB211-GT1 85.3 52.8 No data available
Pratt %Whitney SWIFTPAC60 74.2 51.3 73.1 50.6
Siemens SCC-600 2 x 1 73.4 50.9 72.0 49.9
(Source: 2012 GTW Handbook)

(2) Operability
CCGT is operated only by automatic control of the fuel flow to the GT and starting, normal
operation, and stopping operation can be automated completely regardless of the shaft
configuration. The difference of shaft configuration does not mean any essential difference of
operability. For one-shaft CCGP, since auxiliary steam is ensured from the auxiliary boiler and
operating unit and both the GT and steam turbine are started or stopped, it can start or stop more
quickly than the multi-shaft type.

For multi-shaft 2-on-1, even if other GTs stop because of maintenance, it can continue to
operate with about 50% of the load in the plant.

(3) Start-up Steam

For multi-shaft CCGT, the GT generator can be started together with HRSG when the steam
turbine is disconnected. If steam necessary to start the steam turbine is available from HRSG
after a certain time elapses after the gas turbine start-up, the steam turbine can be started up with
its own steam for flow passage cooling and gland sealing.

In case of the single-shaft configuration, however, the steam for the flow passage cooling and
gland sealing of the steam turbine which must be started up together with the GT is required
from any external source or the operating unit. For this purpose, any auxiliary steam from the
existing boilers or a standalone auxiliary boiler will be needed.

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(4) Footprint Area for Instruction

Since the GT generators and the steam turbine generators are installed individually for
multi-shaft CCGT, the space usage ratio is inferior to one-shaft CCGT. In particular, two
blocks of multi-shaft 1-on1 have more facilities than the other types, i.e., requires a larger
installation area.

(5) Construction Costs

The construction costs of multi-shaft 2-on-1, multi-shaft 1-on-1, and two blocks of one-shaft
CCGT will be compared and evaluated. Each configuration has the same number of GTs and
HRSGs (i.e., two GTs and two HRSGs) and each configuration has a different number of power
generators and steam turbines. The following assumptions are made in order to make a
comparison:
・ The construction cost is proportionate to the physical scale of the plant to the power 0.6.
i.e., (scale of the plant)0.6
・ Cost of steam turbine generators is regarded as 1, of which 30% is for the generator and 70%
is for steam turbine.
Table 4.2-3 shows the results of the comparison and examination. As shown in the table, the
constructions costs of the multi-shaft 1-on-1 is the highest because it has many facilities and the
multi-shaft 2-on-1 has the lowest cost.
Table 4.2-3 Construction cost of CCGT
Configuration Cost for GT and ST

Multi HRSG GT ST GEN ST = 0.7

shaft GT = 3 x 0.3
2-on-1 G:1
Total = 1.6
(Type A) ST: 1 G:1

G:1

Multi HRSG GT ST ST = 0.66 x 0.7 x 2

shaft GT = (1+0.66) x 0.3 x 2
1-on-1 G:1 0.5 0.5
Total = 1.92
(Type B)

G:1 0.5 0.5

HRSG GT ST Generator
Single ST = 0.66 x 0.7 x 2
shaft GT =1.28 x 0.3 x 2
0.5 G:1.5
(Type C) Total = 1.69

0.5 G:1.5

Note: ST is steam turbine.

(Source: JICA Study Team)

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(6) Maintainability and Maintenance Costs

Since the structure of one-shaft CCGT is more complicated than the multi-shaft type because
GT and steam turbine share a common shaft, the disassembly and assembly of the main
equipment are troublesome. In regards to maintenance costs, since two blocks of multi-shaft
1-on-1 have more main equipment than the others, more manpower and processes are required
for maintenance, i.e., higher costs can be assumed.

(7) Effect y of Gas Turbine Outage

As explained above, multi-shaft 2-on-1 CCGT consists of two GTs, two HRSGs and one steam
turbine. CCGT can operate continuously 50% of rated capacity and high efficiency during the outage
of one GT for periodic inspections and trouble. One block of multi-shaft 1-on-1 and one-shaft CCGT
cannot operate during its own gas turbine outage.

(8) Requirements from EDM

EDM has requested that the new power plant shall be as follows:
・ Plant can operate 100% of rated capacity with high thermal efficiency
・ Lowest EPC costs
・ As the fuel gas contract is “Take-or-Pay”, the plant can operate continuously during outages
of one GT for periodic inspections and trouble. Periods of plant outages should be as short as
possible.

(9) Summary of Examination Results

A summary of the results of the evaluation is shown in the following table. As shown in this
table, each CCGT configuration has merits and demerits.

Table 4.2-4 Feature of Type of CCGT Configuration

Comparison Type A Type B Type C
Item Multi-shaft (2-on-1) Multi-shaft (1-on-1) × 2 One-shaft × 2
Output Base -0.4 to -1.4MW* -0.4 to -1.4MW*
Thermal Base -0.2 to -1.0%* -0.40 to -1.0%*
efficiency High total plant High efficiency at plant High efficiency at plant
efficiency partial load partial load
Operability Base Equivalent Rapid start/ stop
Auxiliary Auxiliary steam from
Own steam Own steam
steam at start outside
Number of Base Many Equivalent
main facilities GT: 2 GT: 2 GT: 2
HRSG: 2 HRSG: 2 HRSG: 2
ST: 1 ST: 2 ST: 2
GEN: 3 GEN: 4 GEN: 2
Installation Base Slightly wide Slightly compact
area
Construction Base High Slightly high
costs
Actual results Many Many Limited manufacturers
and remodeling required
Maintainability Base Equivalent Disassembly of main
equipment is slightly
complicated

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Comparison Type A Type B Type C

Item Multi-shaft (2-on-1) Multi-shaft (1-on-1) × 2 One-shaft × 2
Maintenance Base Slightly high because of Almost equivalent
cost many operating
equipment and facilities
(Source: JICA Study Team, 2012 GTW Handbook)

The concerned power generation plant will be built in southern Maputo city in Mozambique to
cope with the tight power demand in Mozambique. For this plant, one unit operation is assumed
for the present and continuous operation of the power plant with as high efficiency as possible is
required.
Globally, in the case of plants that require high efficiency operation and high capacity factor,
multi-shaft 2 and more-on-1 CCGTs are installed.

The JICA Study Team recommends multi-shaft 2-on-1 CCGT since it is superior in the total
efficiency of the power plant and it allows partial load operation with high efficiency of about
50% even if a GT stops because of periodic maintenance, etc., and it has maintenance costs. In
addition, after an investigation of the gas supply amount, site area, and applicable CCGT
models to be supported, 70-110 MW of CCGT rated capacity was recommended to EDM in the
first workshop and was approved.

4.2.3 The Layout of CCGT

(1) Beluluane site
An example of a 50 MW class CCGT plant layout and its installation at the Beluluane site are
shown in Figure 4.2-2 and Figure 4.2-3. The main equipment, related equipment, and work area
for periodic inspection can be located in a 1 ha area (100 m x 100 m) with remaining land of
100 m x 50 m still available.

Cooling Tower
Stack

Waste Water
Treatment
Plant

Heat Recovery
Steam Generator
100000

Steam Turbine Generator

Workshop

Demineralize Water Plant,

Demineralized Water Tank &
Gas Turbine
Raw Water Tank
Generator

GIS &
Transformer
Fuel Gas
Compressor
Electrical room &
Control room

Air Compressor
100000

(Source: JICA Study Team)

Figure 4.2-2 An example of a 50 MW class CCGT Plant Layout

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Cooling Tower
Stack

Waste Water
Treatment
Plant Beluluane
Heat Recovery
Steam Generator
Substation

Steam Turbine Generator

Workshop

Demineralize Water Plant,

Demineralized Water Tank &
Gas Turbine
Raw Water Tank
Generator

GIS &
Transformer
Fuel Gas
Compressor
Electrical room &
Control room

Air Compressor

100000

(Source: JICA Study Team)

Figure 4.2-3 An example of a CCGT Layout at the Beluluane site

(2) The layout of CTM Maputo site

a. Site Conditions
As a result of a hearing with EDM and measuring the actual site, the following land is available
for the power plant:

(i) Former coal-fired power station: Yard of 270 m x 96 m (approx. 2.6 ha)
EDM has the intention of separating the power station from the substation located to the east of
the power station and plans to install a fence at the boundary and a road to access the substation
along the boundary to the north of the power station.

(ii) Diesel oil tank yard (approx. 1.1 ha)

The existing GTs will be modified to use natural gas and the existing 5,000 kl and two 220 kl
diesel oil tanks will be removed.

(iii) Existing No. 3 gas turbine area (approx. 0.3 ha)

EDM has approved the installation of the utilities of the new plant. However, some space for
maintenance for No. 3 GT will be left untouched.

(iv) Terminal points for fuel gas and portable water

Fuel gas: To branch from a new gas station
Water: To branch from the vicinity of the booster pump in the northwest of the CTM Maputo
power station

b. Power Plant Layout

Aero-derivative GTs or heavy duty industrial GTs can be used for the 110 MW class multi-shaft

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type 2-on-1 CCGT. Typical CCGT layouts using each GT are shown in Figure 4.2-4 and Figure
4.2-5. In either case, two GT Generators, two HRSGs, one steam turbine generator, and utility
equipment such as switching gear, water treatment equipment, and wastewater treatment
equipment fit in an area of 150 m x 100 m.
Emergency
Fuel Gas Diesel GIS &
Station Generator Transformer

Demineralize Water Plant,

Demineralized Water Tank & Control Room &
Raw Water Tank Electrical Building

Waste Water
Treatment Plant
Generator
Generator
Air Inlet
Room

100000
Steam Turbine Air Compressor
Gas Turbine Gas Turbine

Condenser
Workshop

Heat Recovery Heat Recovery

Stem Generator Stem Generator
(HRSG) (HRSG)

Dosing Cooling Tower

Stack
Stack

150000

(Source: JICA Study Team)

Figure 4.2-4 Typical CCGT Layout of a heavy duty GT

Air Cooled
Condenser
Fuel Gas
Gas Turbine Compressor
Generator
100000

Demineralize Water Plant,

Demineralized Water Tank &
Raw Water Tank

Waste Water
Treatment
Heat Recovery Plant
Steam Turbine Steam Generator
Generator

Electrical Room &

Control Room

150000

(Source: JICA Study Team)

Figure 4.2-5 Typical CCGT Layout of an aero-derivative GT

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Using the site conditions of CTM Maputo and a typical plant layout for reference, three cases of
plant layouts were studied.

1) Case 1: Installing the main facility in the diesel oil tanks area and the utility facility in the
existing No. 3 gas turbine area

In case 1, the area of the former coal-fired power plant facilities can be used as the site for future
plant extension. In addition, expenses for land clearing and demolition removal can be reduced
because the foundation of the thermal power plant facilities is available at the site of the former
coal-fired power station. The tie-in point of portable water and fuel gas are close by. Sufficient
space is also available for construction and maintenance for the power plant facilities. Moreover,
because the site is far from the northern boundary of the power station where residents live, there
is no need to protect against noise, such as installing soundproof barriers.

EDM intends to modify the control equipment of the existing Nos. 2 and 3 GTs and install a
distributed control system (“DCS”) in the central operation room of the new power plant, so that
the existing GTs can be started from the central operation room in case of an emergency
shutdown, e.g., if the new power plant stops due to trouble. Both the equipment and site can be
operated and managed combining the existing Nos. 2 and 3 GTs and new power plant.

270m

New Gas
Station
Portable
Water Tie-in
point
145m
Air Cooled
Condencer

Gas Turbine Generator

Steam Turbine Generator Heat Recovery

Steam Generator
Fuel Gas
Compressor

Demineralize Water Plant,

Demineralized Water Tank &
Raw Water Tank

Electrical room &

Waste Water Control room
Treatment
Plant

125m

(Source: JICA Study Team)

Figure 4.2-6 Plant Layout (Case 1)

2) Case 2: All facilities installed at the former coal fired power plant area
Taking into consideration any future construction for power plant extensions, the power plant
will be constructed from the side of the former coal fired power plant turbine building behind

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the power station. The longitudinal direction is 96 m, i.e., narrower than 100 m. It will be even
narrower if an access road to the switching yard is built along the northeastern boundary fence.
Consequently, sufficient work area will not be available during power plant construction work
and for maintenance and inspection. In addition, the former coal fired power plant site needs to
be demolished and cleared for construction of the new power plant. The site is closest to the
substation as compared with the other cases and the distance over which cables would be laid
down to the substation is short. As there is a nearby residential area, noise prevention measures
may be necessary. For future extension of the power plant, both the part of the former coal fired
power plant site that will become available after construction and the diesel oil tank area will be
reserved.

270m
150000

Control room
Electrical room &

Steam Generator
Heat Recovery Steam Turbine Generator
Plant
Treatment
Waste Water

New Gas
Station
Raw Water Tank
Demineralized Water Tank &
100000

Demineralize Water Plant,

Portable Compressor
Fuel Gas

Water Tie-in
Gas Turbine Generator

Condencer
Air Cooled

point

145m

125m

(Source: JICA Study Team)

Figure 4.2-7 Plant Layout (Case 2)

3) Case 3: All facilities installed in the current diesel oil tank area
The 110 MW class multi-shaft 2-on-1 CCGT does not fit into the diesel oil tank area. The
equipment that spills over must be installed in the former coal fired power plant area. It is
therefore necessary to demolish the former coal fired power plant area. The area for future
power plant extension will be smaller than case 1 and the land area will be an odd shape.

In case 3, the tie-in points of fuel gas and portable water are close, like in case 1, and the
distance over which pipes must be laid down is short. There is a sufficient work area for
construction work and inspection and maintenance work for the equipment and power plant
extension.

Since the plant is far from the northern boundary of the power station where residents live, there
is no need to have any noise protection such as installing soundproof barriers.

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270m 270m

New Gas
Station
100000

Waste Water
Demineralized Water Tank &

Treatment
Demineralize Water Plant,

Plant
Portable

Raw Water Tank

Compressor
Fuel Gas

Electrical room &

Water Tie-in

Control room
point
145m
145m
Gas Turbine Generator

Steam Generator
Heat Recovery

150000
Steam Turbine Generator
Condencer
Air Cooled

125m 125m

(Source: JICA Study Team)

Figure 4.2-8 Plant layout (Case 3)
Table 4.2-5 shows the results of studying cases 1) to 3) above. Case 1, which does not need the
former coal fired power plant area to be demolished nor any countermeasures taken against
noise and ensures that a large area
125mof land is available for future power plant extensions, was
recommended by the JICA Study Team to EDM at the Workshop and it has been approved. It
has been decided that a detailed layout study of this case will be advanced.
Table 4.2-5 Feature of Each Case of CCGT

Case Results
・Area of former coal fired power plant can be used for any power plant extensions
in the future.
Advantages ・Very close to the new gas station and portable water tie-in point.
Case 1 ・No need for any noise protection on the boundary line.
・Sufficient construction and maintenance work area.
Disadvantages ・Existing No. 3 GT area is used.
・Site area can be reserved for future extensions of the power plant.
Advantages
・Close to substation.
Case 2 ・Site for the power plant is slightly narrow.
Disadvantages ・Therefore, sufficient construction and maintenance work area is not available.
・Noise protection is needed on the site boundary line.
・Very close to the new gas station and portable water tie-in point.
Advantages ・No need for any noise protection on the boundary line.
・Sufficient construction and maintenance work area
Case 3
・Area for future power plant extension is narrower than the other two cases.
Disadvantages ・Facility protrudes into the former coal fired power plant area, making layout
inappropriate.
(Source: JICA Study Team)

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4.3 Condenser Cooling System

4.3.1 Outline
There are three types of cooling facilities for the condenser of the steam turbine in this power
generation plant, i.e., once-through cooling system, wet cooling tower system, and air-cooled
condenser system. The merits and demerits of the cooling systems vary depending on the site
peripheral conditions, operation conditions, and economic conditions such as power cost and
fuel cost. This examination of the three types of cooling facilities has been done from the
viewpoint of mechanical and constructional technology, and economic and environmental
influences to select the cooling system suitable for this project.

While the performance of the GT which is the topping cycle in CCGT has no influence on the
type of cooling system, the performance of the steam turbine which is the bottoming cycle has
an influence on it.

4.3.2 Mechanical examination of condenser cooling system

Table 4.3-1 summarizes the characteristics of the three types of condenser cooling systems.
Table 4.3-1 Features of Condenser Cooling Systems

Cooling Method Once-through Type Wet Cooling Tower Air-cooled Condenser

Cooling medium Sea water, river water Fresh water Air
Characteristics of - High construction costs - Construction costs - Construction costs
construction - Environmental cheaper than cheaper than
assessment required once-through type once-through type
Characteristics of - Highest output and - Needs a lot of water for - No cooling water
O&M efficiency makeup to the cooling - Relatively bad output
- High operation tower and efficiency
maintenance costs - Slightly bad vacuum - Low operation
and plant efficiency maintenance costs
- Water quality needs to
be maintained and
managed
Main facilities Water supply/ discharge Cooling tower, Air-cooling condenser,
channel/ tube/ facility, circulating water facility fan
circulating water facility,
screen
Facility cost Highest costs Cheaper than Cheaper than
once-through type once-through type
Cooling medium
None High None
costs
License of harbor
usage Required None None
(Source: JICA Study Team)

(1) Once-through Cooling System

The once-through cooling facility uses seawater or river water as the coolant to return steam to
condensate.

Since the cooling medium of water is abundant and the vacuum of the condenser can be lowered,
the output and efficiency of the steam turbine are the highest of the three cooling systems.
However, facility costs, maintenance costs, and management costs are the highest because of the

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construction facility for water intake and discharge, equipment to remove debris from the sea,
and the facilities to keep the tube in the condenser clean. In addition, because of hot drainage,
environmental impact studies and permits/ licenses from harbor authorities, etc., are required.

(2) Wet Cooling Tower System

Since the forced ventilating cooling facility does not require any water supply/ discharge
facilities, the construction costs of this system are cheaper than those of the once-through type
but a large amount of water is required for makeup water to the cooling tower. In addition, since
the vacuum of the condenser is slightly lower than that of the once-through type, the output and
efficiency of the steam turbine is slightly lower. Since no hot water is discharged into the sea, an
environmental impact study and permits/ licenses from the harbor authorities, etc., are not
required. Since the circulating water in the cooling tower makes direct contact with the air and
part of it is evaporated to discharge heat, impurities and gas absorbed in the circulating water
and impurities in the supply water are condensed causing bad effects, e.g., corrosion of devices
and sticking of scales and slime, etc. To prevent these bad effects, water quality management
and chemicals are needed to maintain water quality.

(3) Air-Cooled Condenser System

Since air-cooling condenser systems use the air as the coolant and a higher vacuum is required
compared to the other two types, the output and efficiency of the steam turbine are low. Since
no water is used as the coolant, there is no need for a water supply/ discharge facility or a pump
to circulate a large amount of water. In addition, water quality does not need to be maintained.
The construction costs, operation costs, and maintenance costs are cheap. Since this system does
not use seawater as the coolant similar to the cooling tower type, an environmental impact study
and permits/ licenses from the harbor authorities, etc., are not required.

The figure below shows the schematic system diagrams of the three types of cooling facilities.

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Steam
Turbine
Heat Recovery Steam Steam Heat Recovery Steam Steam Heat Recovery Steam
Generator Turbine Generator 150m 3 /h Turbine Generator

Make-up Water
for Plant Condense Condense Air Cooled
r Make-up Water r Condenser
20m 3 /h
for Plant
Make-up Water
Circulating Pump 7000m 3 /h 20m 3 /h for Plant
15m 3 /h
20m 3 /h
Make-up Water
300m 3 /h
7000m 3 /h
River/Sea

Blow down 135m 3 /h Cooling Tower Circulating Pump

Condensate Pump Condensate Pump Condensate Pump

Once-through Cooling System Cooling Tower System
Air Cooled Condenser System

Schematic Diagram of Cooling System

(Source: JICA Study Team)

Figure 4.3-1 Schematic diagram of cooling system

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4.3.3 Overall study of water intake facilities

Three types of cooling systems may be used as the condenser cooling system of a steam turbine:
once-through cooling system, mechanical draft cooling tower system, and air-cooled condenser system.
This section studies the applicability of these three condenser cooling methods from the viewpoint of
civil engineering technology.

(1) Cooling water consumption and intake facilities

1) CTM Maputo site

If a once-through cooling system is employed at the Maputo site, condenser cooling water of
7,000m3/h will always be necessary in addition to make-up water of 20m3/h for the plant.
Consequently, an inlet channel of about 1.2 km long and an intake tower must be constructed. In the
case of a wet cooling system, cooling make-up water of about 300m3/h will be necessary. However,
because the city water pipeline continues to the neighborhood of the site, no large-scale, additional
facilities connecting to a water source will have to be constructed. If an air-cooling condenser is used,
no water other than the make-up water for the plan will be necessary.

Water intake point of former coal fired power Intake/outlet facilities (expanded view)
plant (complete view)
(Source: JICA Study Team)

Figure 4.3-2 Water intake facilities for the old Maputo coal-fired power plant

(Source: JICA Study Team)

Figure 4.3-3 Intake facilities (conceptual drawing)

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2) Beluluane site
At the Beluluane site, water of 3,500m3/h will always be necessary for cooling the condenser in
addition to make-up water of 10m3/h for the plan if a once-through cooling system is employed.
However, there is no water source near the site nor is there a place where river water or sea water can
be used. It will therefore be necessary to construct an inlet channel of 7 to 8 km long connecting to the
Matola River. In the case of a wet air cooling system, about 150m3/h of cooling water is necessary and,
like the once-through cooling system, constructing water conveyance facilities will be necessary.
Water other than make-up water for the plant will not be needed if an air-cooling condenser is used.

Water Intake point is 7-8 km

downstream from the Site for Once-
through cooling system

(Source: JICA Study Team)

Figure 4.3-4 Intake facilities (conceptual drawing)

3) Comparisons
Comparisons of intake facilities in both locations are as shown in the table below.
Table 4.3-2 Comparisons of intake facilities
Cooling Wet Cooling Air-cooled
Site Item Once-through Type
Method Tower Condenser
Make-up water 20m3/h 20m3/h 20m3/h
Cooling water - 300m3/h -
CTM 7,000m3/h
Expendable
Maputo (sea water)
water Water for cooling
Site Need to construct - -
condenser inlet channel of
1.2km
Make-up water 10m3/h 10m3/h 10m3/h
Cooling water 150m3/h
Need to construct
inlet channel
- -
7-8km from
Beluluane Expendable Matola River
Site water
3,500m3/h
(river)
Water for cooling
Need to inlet - -
condenser
channel 7-8km from
Matola River
(Source: JICA Study Team)

(2) Assessment of soundness of existing intake facilities

Since the Maputo power plant had coal-fired power facilities, it used sea water to cool the condenser.
The water on the sea area in front of the Maputo power plant recedes to a considerable distance at low
ebb and sea water was pumped up at a point of about 1.2 km from the shore. At present, the intake
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pump and pipeline have been removed and only a pipe bridge of steel-reinforced concrete and a pump
house are left. As a result of the site survey, the facilities have been found to have been substantially
degraded and a conclusion has been reached that it would be difficult to reuse the existing
structures.(Figure 4.3-5 shows photographs of the current situation of the intake facilities at the old
coal-fired power plant.

Intake bridge for old Maputo coal-fired power plan Conspicuous exposure of reinforcing bars
(partially damaged)
(Source: JICA Study Team)
Figure 4.3-5 Assessment of soundness of existing intake facilities

4.3.4 Study from viewpoint of economics

This section evaluates the economics of the three cooling systems described above in terms of life time
cost of the necessary total costs, including construction costs, O&M construction, fuel costs, and
make-up water costs, converted into present values.

(1) Setting conditions

This study is applied to CCPPs that use 30- to 40-MW GTs currently available on the world market.
Of the five models of CCGTs, LM6000PD has the highest capacity. Therefore, this model is used to
advance our study on the selection of a cooling system.

(2) Ambient conditions for study of conditional site

The thermal load of the cooling system of a CCGT significantly varies depending on the ambient
conditions. Therefore, this study is conducted under the annual average ambient conditions. For this
reason, it was decided to calculate the average ambient conditions of the site based on the results of
the site survey. The specific values of these conditions are as follows:

Average dry bulb temperature 23.0oC

Average relative humidity 63.4%
Average wet bulb temperature 18.3oC
Average river water temperature 23.2oC

(3) Economic conditions

The following economic indexes are used:

Fuel price 5.6 USD/GJ

Water expense 1.0 USD/m3
O&M expense Fixed: 4.0 USD/MW/Y, flexible: 8.8 USD/kWh/Y
Discount rate 10.0%
Assessment period (years) 25.0 years
Construction period (years) 3.0 years
Facility utilization rate (%) 83%

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(4) Study results

The results of the assessment are shown below. The kWh cost is the lowest if the air-cooled condenser
method is employed.
Table 4.3-3 Feature of condenser cooling system
Once-through Cooling Air-cooled
Cooling System
Cooling System Tower System Condenser System
Efficiency (%) 51.86 51.71 50.49
Gross (MW) 96.8 96.5 94.2
Output Net (MW) 94.4 93.8 92.2
Salable (GWh/y) 661.6 657.4 646.1
EPC Cost (USDmil) 130 109 112
Fuel (USDmil/y) 26.4 (Annual gas consumption: 4.71MGJ)
Cost O&M (USDmil/y) 3.9 3.9 3.5
0.14 2.24 0.14
Water (USDmil/y)
(0.14 Mm3/y) (2.25 Mm3/y) (0.142 Mm3/y)

Lifetime cost USDmil 360.3 357.2 340.2

kWh cost USc/kWh 7.31 7.30 7.06
(Source: JICA Study Team)

(5) Sensitivity analysis

The sensitivity of the Higher EPC Cost case in which civil engineering costs, which accounts for about
15% of the EPC cost, increase 30%, and the Gas Price 2% escalation case in which fuel gas prices rise
2% were compared against the above base case. As a result, the air-cooled condenser system was
found to be economically advantageous over both the other cases. The difference tended to be
conspicuous especially when fuel prices rise.

410
400
Lifetime cost (Million USD)

390
380
370
360
350 Base
340 Gas Price 2% escalation
Higher EPC cost
330
Once-through Wet cooling Tower Air cooled condenser
(Source: JICA Study Team)

Figure 4.3-6 Schematic Diagram of Cooling System

4.3.5 Overall judgment

As a result of comparing and studying the three types of cooling systems for the steam turbine cooling
system, i.e., once-through cooling system, wet type cooling tower system, and air-cooled condenser
system, the conclusion was reached that the air-cooled condenser cooling system is the most suitable
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for this site, as shown in the table below.

Table 4.3-4 Overall judgment of steam turbine condenser cooling system

Cooling Once-through Cooling Air-cooled

System Method Cooling System Tower System Condenser System

Not Recommended: Not Recommended Recommended

 Time consuming  Water cost (1USD/m3) is  Need to consider impact
approval/ permit very high assessment of noise and
process from MPDC vibration
 Consideration of the
impact of EDM project
Evaluation
from deforming
near-shore / moving
sediment
 High construction costs
for new intake system
and pipeline.

(Source: JICA Study Team)

4.3.6 Risk to water intake of development of surrounding sea areas

At present MPDC holds the rights of developing the Maputo Port through 2033 and any development
in this region must be approved and authorized by MPDC. In addition, according to the master plan,
MPDC is planning to expand the Maputo Port area near the project. If water intake facilities are
installed in this sea area, there is the concern that the water intake may be influenced by changes of the
tidal current resulting from changes of the beach profile and encroachment and deposition of marine
sediment from the new sea area development. It is therefore necessary in advance to simulate and
verify the influences based on the development plan. If the surrounding sea areas are developed after
the power generation operation of this project has begun, it will be difficult to avoid or minimize the
influences on the water intake. From the viewpoint of long-term operation, it is considered that
constructing new intake points in the area where there is a possibility of development is not the best
policy, except in the cases where there are no alternatives.

Iron ore stock yard CTM Maputo Site

MPDC jurisdiction area

Extension Coal Terminal

Extension Cargo Terminal 32

(Source: JICA Study Team)

Figure4.3-7 Sea area development around project site

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 Chapter 5

Site Conditions
 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Chapter 5 Site Conditions

5.1 Topography and Geology

5.1.1 Topography
The proposed site is located in the existing Maputo Thermal Power Station (CTM site),
which is approximately 3 km west of the city center of Maputo city and close to the border
of Matola city. A railway linking Port Maputo and Swaziland runs immediately north of the
CTM site and a highway (EN2) is situated to the north of the railway.
The ground level of the site was raised by 1.5 to 2.0 meters when the former coal-fired
power plant was constructed in the 1950s, and the present ground level is approximately 3.3
m above MSL of Port Maputo. Since the embankment of the highway located to the north
acts as a topographic divide, rain that falls on the north side of the highway generally does
not flow in the direction of the CTM site.
As shown in Figure 5.1-1, the area surrounded by the railway embankment once suffered
from inundation caused by heavy rain. Several years ago, drainage channels with sufficient
capacity were provided on both sides of the railway embankment. Since then, no flood
damage has been reported in this area.

Infulene River
Flood-prone Railway

Highway (EN2)

CTM site

(Source: JICA Study Team)

Figure 5.1-1 Topographical situation around CTM site

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5.1.2 Geology

As shown in Figure 5.1-2, the stratigraphic sequence occurring at the site location consists of
Holocene superficial deposits that overlie Pleistocene (Congolote and Machava formation)
and Pliocene (Ponta Vermelha formation) geological units as described in the following
paragraphs.
Holocene deposits make up all of the surface soils of the surveyed area, comprising landfill
materials used to modulate terrain morphology in previous interventions. These materials are
mainly constituted by silty-sandy soils with coal fragments and vegetal residues.
By this description, one assumes that most of it is of alluvium nature, which might also occur
in the depths beneath the landfill deposits. Given these circumstances, it will be extremely
difficult to differentiate one from the other and all should be treated as one unit.
The Pleistocene unit, known as the Congolote formation (Qco), is mainly described as a
coarse to fine-grained sandy soil, poorly consolidated, of white, yellow or orange coloration.
It represents aeolian materials of continental dunes, constituting a sandy stratum that overlies
succeeding geological units.
Underlying the Congolote formation is the Machava formation (Qmc), mainly described as
an interbedded sedimentary deposit of clayey sands with carbonated, salty and ferruginous
formations and with a basal conglomerate.
Although its lateral limits are generally well defined, this geological unit may not be
represented throughout all of the lower Pleistocene, enabling the Congolote formation to
settle directly on the Pliocene unit Ponta Vermelha through a stratigraphic unconformity.
Ponta Vermelha formation (TPv) comprises sand, siltstones and sandstones of reddish to
yellowish coloration, occasionally with a ferruginous hard cover.

（Source: Mozambican National Department of Geology）

Figure 5.1-2 Geological setting around the Project site

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Given the presented geological conditions, there are no structural evidences of tectonic
nature on the referred geomorphologic unit as the deposited sediments overlie any bedrock
that may exhibit any type of fragmentation. For this reason, there are no geological structural
constraints at the proposed site.
Field investigation by standard penetration test (SPT) was conducted at CTM site. The
locations of the boreholes (11 nos.) are exhibited in Figure 5.1-3.

(Source: JICA Study Team)

Figure 5.1-3 Location of boreholes

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The results of the SPT are summarized in the following table.

Table 5.1-1 Results of standard penetration test

(Source: JICA Study Team)

The following points highlight the results obtained by the field investigation.

 The geological model is generally represented by superficial landfill deposits in a loose

density state, with a generalized thickness of 2-3 m that overlies Pleistocene sandy soils
with occasionally interbedded weathered sandstone and calcarenite.

 In general, the N-value, which represents soil resistance, increases with depth with
occasional breaks, particularly when intersected with clayey interbeds.

 All boreholes feature a minimum of 4 consecutive SPT refusals (> 50 blows per 25 mm
penetration), starting at depths ranging between 5 m and 15 m.

For sandy soils, a layer with an N-value greater than 50 is deemed suitable for foundation
support1. Accordingly, it is concluded that only the geological layer with an N-value of more
than 50 is rated well enough for the foundation of heavy loads, such as major machines and
structures.

1
Specifications for Highway Bridges (2002), Japan Road Association.

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5.2 Meteorological Conditions

5.2.1 General
For general information about meteorological conditions of the site, see Section 11.2.1 of this
report, “Natural Environment Conditions.”

5.2.2 Characteristic of Tropical Cyclones that hit Mozambique

Tropical storms2 originating from the Southwest Indian Ocean Basin hit Mozambique once a
year on average and lesser-magnitude tropical depressions hit three to four times per year.
The most frequent destinations of Mozambique-bound cyclones are the coastal area between
Pemba and Angoche and the area near Beira. In Mozambique, the cyclone season lasts from
November to April but more than 90% of the tropical cyclones that hit Mozambique occur from
December to March.
Figure 5.2-1 shows the frequency of cyclone occurrences during the 75-year period from 1911
to 2000 and the path of the four major cyclones that hit Mozambique recently.

(Source: Atlas for disaster preparedness and response in the Limpopo Basin)

Figure5.2-1 Cyclone frequency and paths

2
A tropical storm is defined as a tropical cyclone with a maximum wind speed of 34 knots or higher. A
tropical cyclone with a maximum wind speed of less than 34 knots is called a tropical depression and is
given a specific name. The two types of tropical cyclones are differentiated by whether the maximum
wind speed is lower or higher than the threshold of 34 knots.

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It is inferred that the southern coast of Mozambique, which includes Maputo city, receives
fewer cyclones than the northern and central coasts do. Furthermore, it has been reported that
tropical cyclones that hit southern Mozambique tend to lose strength, since they dissipate energy
while crossing Madagascar before hitting Mozambique.

5.2.3 Tropical Storms in Early February

In February 2000, two tropical cyclones3 landed in Mozambique and devastated the economic
and social infrastructure across the country and displaced millions of people. The maximum
total precipitation of 653 mm was a record for this month and accounted for approximately 80%
of Maputo’s normal annual precipitation of 800 mm. About 70% of the normal annual
precipitation fell in just three days (from February 5 to February 7).
Figure 5.2-2 shows satellite images showing the progression of the first tropical depression that
hit Mozambique in early February. In this figure, the red and orange colors show the position of
the depression. Figure 5.2-3 shows the daily precipitation recorded at Maputo city from
February 3 to February 7.

(Source: Atlas for disaster preparedness and response in the Limpopo Basin)

Figure 5.2-2 Satellite image showing the progression of the first tropical
depression that hit Mozambique in early February

3
One of these was Cyclone Eline, which traversed almost the entire Indian Ocean and made devastating
strikes on Madagascar and Mozambique.

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400.0

350.0

300.0
Precipitation (mm)

250.0

200.0

150.0

100.0

50.0

0.0
3 Feb. 4 Feb. 5 Feb. 6 Feb. 7 Feb. 8 Feb.
(Thu.) (Fri.) (Sat.) (Sun.) (Mon.) (Tue.)
Day

(Source: Atlas for disaster preparedness and response in the Limpopo Basin)

Figure 5.2-3 Daily precipitation recorded at Maputo City from February 3 to 7, 2000

On February 6, the No.1 GT and No.2 GT buildings in CTM site suffered from flood damage.
As explained in Section 6.7.6, it can be concluded that the damage was not caused by
inundation from river water or storm surges, but was due to the poor drainage within the CTM
site.

The tropical storms of early February were followed by Cyclone Eline, which moved into the
central region of Mozambique and caused excessive rainfall in that area. However, the southern
region including Maputo was not severely affected by this cyclone.

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 Chapter 6

Basic Design
(A part of this chapter has been removed because of confidential information.)
 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Chapter 6 Basic Design

6.1 Design Philosophy

6.1.1 Project Outline

The planned CCGT, which is the first combined cycle power plant in Mozambique, will be
installed in the CTM Power Station. The multi-shaft, 2-on-1 CCGT will consist of two
GTs/generators, two HRSGs, one steam turbine/generator and related facilities and its net
output will be 70-110 MW.

(1) The maximum average air temperature in Maputo is expected to be 28.4C over the next five
years with many days of 35C or above. Therefore we will evaluate the effectiveness of the
GT intake cooling system with water spray and plan the installation if it is found to be
effective.
(2) The fuel natural gas will be supplied by ENH.
(3) As to the cooling system of the steam turbine condenser, as a result of the JICA Study
Team’s evaluation of technologies and economics of a once-through cooling system, a wet
cooling tower system, and an air-cooled condenser, it was determined to use the air-cooled
condenser.

6.1.2 Operation Requirements

The main components and their auxiliaries shall be designed to ensure that trouble free starts
and operation are achieved throughout the design life of the new plant. Adequate redundancies
for auxiliary facilities and equipment shall be made available to achieve high availability. The
main components and their auxiliaries shall be designed to be able to start and go to full load by
the push of a single start button. The entire plant shall be suitable for continuous power load
operation.

(1) Plant Duty

The new plant shall have high efficiency and reliability based on proven advanced technology.
The new plant shall be so designed as to withstand the anticipated annual operating scheme
specified in this specification with an annually averaged availability factor not less than 86.8%,
which is defined in ISO 3977-9:1999(E) Gas turbines - Procurement - Part 9: Reliability,
availability, maintainability and safety.

(2) Start-up Time Schedule Requirements

The start-up time shall be as short as possible to cope with the function of this new plant. The
new plant shall be designed to meet such start-up times as specified in the following table.

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The start-up time shall be defined as the time required from the push of the start button to the
full load conditions, provided that a condenser vacuum is built and the new plant is ready for
start. The time for air purging of special volume post GT and synchronization shall be excluded

Table 6.1-1 Requirement unit starting hours of each mode

Type of Start-up Time (min.)
Cold start after stop of more than 36 hours Max. 240
Warm start after stop of less than 36 hours Max. 180
Hot start after stop of less than 8 hours Max. 120
Very hot start after stop of less than 1 hour Max. 60
(Source: JICA Study Team)

(3) Service Life Time

The new plant and associated equipment shall be designed and constructed for the service time
as specified below:

Minimum Service Time = 30 years

Equivalent Service Hours = 218,124 hours on a full load basis 1

The new plant shall be designed for a continuous load operation with more than 6,132 actual
operating hours per year on the basis of a full load. The necessary hours for starting and shut
down cycle are not included in the above operating hours.Through the service time, the new
plant and associated equipment shall continue to be operated with high efficiency, high
reliability and excellent economy.
Any components of which service lives may be less than the above figures shall be designed for
ease of replacement and maintenance.

(4) Start-up and Shut Down Times

The start-up and shut down operation of the new plant shall be performed automatically from
the Central Control Room (“CCR”).
Full supervisory and control functions shall be provided for the safe, reliable and efficient
operation of the new plant.
The new plant shall be capable of being auto-synchronized and initial-loaded from the CCR.
As a basis for design of the new plant, it is assumed that the new plant shall operate on a full
load basis for the service time of 30 years, during which the high efficient and reliable operation
shall be maintained.

1
) Equivalent Service Hours: 24 x 365 x 30 x Plant Load Factor 83%

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For the design requirements as stated above, the following annual start-up times shall be
considered:

Table 6.1-2 Requirement Plant Start Times for Design

Total Times through
Type of Start Annual Times
Service Time
Cold start (shut down > 36h) 2 60
Warm start (shut down < 36h) 5 150
Hot start (shut down < 8h) 30 900
Very hot (shut down < 1h) 5 150
Total 42 1,260
(Source: JICA Study Team)

6.1.3 Control and Operation Philosophy

(1) Plant Automation

The degree of automation is such that the start-up/shut down sequential control and the
protection of the new plant shall be fully automated to enable overall supervision of the new
plant by operators at the CCR. However, the start-up/shut down control sequence shall include
break points to allow the operator to intervene and provide normal assistance as needed.

The start-up/loading procedures, including draining and venting of the new plant, shall be
selectable and controlled automatically dependent upon such state conditions of the new plant as
very hot, hot, warm, or cold status.

(2) Plant Operation

The CCR shall be located in the new turbine building of the new plant and be equipped with
state-of-the-art Distributed Control System (“DCS”) with a data logging system so that
generated power can be automatically controlled to meet demand. The operator console, which
consists of a Liquid Crystal Display (“LCD”) for monitoring of operating conditions and
keyboard panels with mouse for operation of the new plant, will be installed as the operator
console in the CCR. The LCD operation will be employed to make a man-machine interface
easier and to facilitate monitoring and operation and higher operating reliability.

The Central Processing Unit (“CPU”) shall be of duplicate configuration using the standby
redundant system to ensure the reliability of the control system. A Switching operation of
generator circuit breaker shall also be performed from the DCS located in the CCR. A
Switching operation of electrical circuits in 132/230 kV substations shall be performed from the
DCS located in the substation control room.

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(3) Under and Over-frequency Operation

The GT/generator and the steam turbine/generator shall be so designed that they can withstand
continuous operation under and over frequency from 48.5 to 51.5 Hz under load condition. They
shall also be capable of load operation under the frequency range of 46.5 to 48.5 Hz with
operation time limitation. Control devices required to limit the load operation time as shown
below, shall be provided in consideration of the requirements of the Mozambique Network
System.

Operation Time Limitation

3.0
operation time limitation (sec)

0.0
46.5 Network Frequency (Hz) 48.5

(Source: JICA Study Team)

Figure 6.1-1 Operation time limitation

(4) Operational Vibration Levels

The relative shaft vibration levels of the GT/generator and steam turbine/generator shafts under
any load conditions at the rated speed shall be limited. The measurement method of the shaft
vibration shall be in accordance with ISO 7919 or equivalent standards. The vibration shall be
measured as the unfiltered relative shaft peak-to-peak displacement in the vicinity of the main
journal bearings of the said shafts. The operational vibration levels shall be such as tabled below,
as per ISO 7919-2:2001(E) Part 2 “Large land-based steam turbine generator sets” and ISO
7919-4:1996(E) Part 4 “Gas Turbine Sets”.

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Table 6.1-3 Shaft Vibration Limits

Vibration Level
Type of Equipment
(p-p μm)
GT/Generator ≦80
Steam Turbine/Generator ≦80
(Source: JICA Study Team)

The vibration levels of the GT/generator and steam turbine/generator shafts shall not exceed 80
μm throughout the Reliability Test. Should the vibration level of any equipment exceed the
specified value during the Reliability Test of two weeks, then the Test shall be cancelled and a
new two weeks Test shall be repeated after the vibration level problem has been rectified. After
taking-over of the new plant, vibration levels shall not exceed the values during the Defect
Liability Period.

The relative vibration level at the alarm point shall be set at the level not more than 120 μm for
both the GT/generator and the steam turbine/generator. The trip value shall be set at 240 μm, if
it is acceptable depending upon the operating experience of the same types of the GT/generator
and the steam turbine/generator.

(5) Power Control

The plant power load will be indirectly controlled by the supervisory control and data
acquisition (“SCADA”) system from the load dispatch center, through the power stations, to the
new plant. The new plant shall be automatically operated after setting the plant power load
demand into the DCS through the operator console by the operator of the new power plant so
that the plant power load demand will be satisfied.

6.2 Study of Basic Technical Issues

6.2.1 Expected Performance of the Mozambique Combined Cycle Gas Turbine

(1) Candidate Models of CCGT

In the international market, there are five models available as combined cycle gas turbines
(“CCGTs”) having a shaft configuration of 2-on-1 and offering a rated capacity of 70-110 MW.
From the viewpoint of operating experience, the GTs of four original equipment manufacturers
(“OEMs) are mature with large operating experience and are deemed to be best suited for the
Project. According to the Gas Turbine World 2012 GTW Handbook, the five models of
combined cycle power plants are as tabulated below:

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Name of OEM of GT Model of CCGT

IHI (GE licensee) 2 x LM6000PD Sprint
IHI (GE licensee) 2 x LM6000PD
Hitachi, Ltd. 2025(2 x H-25)
Rolls-Royce 2 x RB211-GT61
Siemens Power Generation SCC700 2 x 1(2 x SGT-700)

(2) CCGT Performance Data on ISO Conditions

In the said GTW Handbook, performance data of the above models of CCGTs are described at
ISO conditions (101.33 kPa, 15C, 60% RH) on natural gas, although necessary conditions
other than ambient temperature and pressure are not always specified. The performance data of
the five CCGT models are described below:

Model of CCGT Net Plant Output (kW) Net Plant Efficiency (%)
2 x LM6000PD Sprint 120,220 53.0
2 x LM6000PD 110,970 53.6
2025(2 x H-25) 87,800 50.3
2 x RB211-GT61 85,300 52.8
SCC700 2 x 1(2 x SGT-700) 83,630 52.5

(3) Calculation Results of CCGT Heat Balance on Unfired Conditions

Performances of the five models of CCGTs on rated and maximum capacity site conditions
must be predicted to specify the performance requirements of the Plant in the Bidding
Documents. For this purpose, the heat balances at the rated and maximum capacity site
conditions were calculated using the GT performance data on ISO conditions specified in the
said GTW Handbook. The types of GTs to be used for calculation of the CCGT heat balances
and their performance data cited from the said Handbook are shown below:

Table 6.2-1 Performance of Applicable GT Model

LM6000PD RB211-
Model of Gas Turbine LM6000PD H-25 SGT-700
Sprint GT61
ISO base rating (MW) 47.5 42.6 32.0 38.1 31.2
Efficiency (%) 41.3 41.2 34.8 39.4 36.4
Pressure ratio 31.0 31.0 14.7 21.5 18.6
Air flow rate (kg/s) 131.9 124.6 93.9 94.3 94.3
Exhaust gas temp (℃) 448.3 455.0 563.9 503.8 528.3
Fuel gas flow rate (kg/s) 2.31 2.07 1.85 1.94 1.72
(Source: JICA Study Team)

Where, the net specific energy (lower heating value) of the natural gas is assumed to be 49,826

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kJ/kg (40.2MJ/Nm3 at 15C) calculated from the fuel gas data received by the JICA Survey
Team . The correction of the performance data of the above GTs to the site, inlet and exhaust
conditions was conducted in accordance with various correction factors based on the wide
experience of the JICA Survey Team in dealing with this type of data. The inlet and exhaust
pressure loss changes for combined cycle configuration are also predicted. The site conditions
are designated as tabulated below, as per the site survey results:

Type of Site Condition Rated Max. Capacity

Dry Bulb Temperature (C) 28.0 10.0
Relative Humidity (%) 75.0 75.0
Wet Bulb Temperature (C) 24.5 7.9
Barometric Pressure (kPa) 101.3 101.3

The rated site conditions are specified in accordance with ones for the existing GT power plants,
while the maximum capacity site conditions are specified as the monthly averaged minimum
ambient temperature and the relative humidity for the time. The installation capacities of
electrical and auxiliary equipment must be determined to cope with the GT maximum capacity
and the performances of the bottoming system (HRSG and steam turbine) dependent upon it.
The GT maximum capacity is widely changeable depending upon the site ambient conditions
(especially ambient dry bulb temperature). To determine the installation capacities of electrical
and auxiliary equipment, therefore, the site ambient conditions where the GT maximum
capacity is defined must be specified.
According to the records for five years from 2007 to 2011 in Maputo International Airport in
the suburb of the CTM Power Plant, the average lowest air temperatures in the winter months
were +13C to +14C and sometimes +10C to +11C. From the viewpoint of effective use of
the power generation facility, 10C is considered to be the lowest air temperature. Therefore, the
installation capacities of electrical and auxiliary equipment shall be determined to meet the
operating performances of GTs and bottoming system at the ambient dry bulb temperature of
10C. The relative humidity for the ambient temperature is 75%.
To obtain the plant net power output, auxiliary power requirements, including the step-up
transformers under steady state conditions at 100% load of the plant, must be predicted. The
JICA Study Team calculated the plant net power output by using computer plant analysis
software and carrying out calculations for each large-output GT model. The cycle
configurations and parameters of the bottoming system may be variable depending upon
manufacturers of combined cycle power plants. However, the following cycle configurations
and parameters are preliminarily assumed for calculation of CCGT heat balances.

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GT Inlet Air Cooling System Not considered

Exhaust Gas Leakage 0.5%
Cycle Configuration Double-pressure, Non-reheat
Cooling System Air-cooled condenser
Type of HRSG Unfired type
Steam Conditions at Turbine Inlet for Site Rated Conditions
HP Steam
Temperature LM6000PD Sprint: 429C, LM6000PD: 430C, H-25:
500C, RB211-GT61: 450C
Pressure 6.0MPa
LP Steam
Temperature 250C
Pressure 0.5Mpa
Condenser vacuum Depends on the characteristics of the cooling condenser

At this point, because the temperatures of the exhaust gas from the GTs differ by the model, the
high-pressure steam temperatures were calculated taking the exhaust gas temperature of each
model into consideration. Leakage of 0.5% of the exhaust gas flow rate from the GTs is
assumed for the calculation of the heat balance of the bottoming system.

Table 6.2-2 Performance of Applicable CCGT Model

2 x LM6000PD
CCGT Model Sprint
2 x LM6000PD 2025(2 x H-25) 2 x RB211-GT61
2
Max Max Max Max
Site Condition Rated1 Rated Rated Rated
Cap Cap Cap Cap
Plant Gross Power
108.8 124.2 93.2 116.3 73.8 83.5 74.9 87.9
Output (MW)
Gas Turbine (MW) 83.0 94.8 70.9 88.7 48.0 53.8 52.4 61.8
Steam Turbine (MW) 25.8 29.4 23.3 27.6 25.8 29.7 22.5 26.1
Plant Gross Thermal
52.5 53.9 52.4 54.3 47.8 50.6 52.4 54.5
Efficiency (%)
Auxiliary Power
2.3 2.5 1.9 2.2 1.5 1.6 1.6 1.7
(MW)
Plant Net Power
106.5 121.7 91.3 114.1 72.4 81.9 73.3 86.2
Output (MW)
Plant Net Thermal
51.4 52.8 51.3 53.1 46.8 49.7 51.3 53.4
Efficiency (%)
Note: 1Rated: Ambient temperature 28C,

2-Max Cap: Ambient temperature10C

(Source: JICA Study Team)

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From this table of the calculation results, it was calculated that the net power output of the
CCGT models under the rated site conditions is 72.3 to 106.5 MW or 86 MW on average.
Therefore, the net output of these power facilities is 85 MW and, taking into consideration the
appropriate likelihood for the above calculated value, the net power output will be specified on
the purchase specification as 70 MW to 110 MW to encourage many parties to participate in the
bidding.
The net thermal efficiency of the power generation facilities under the rated site conditions was
calculated to be 46.8 to 51.4%. Therefore, the net thermal efficiency of these power facilities is
specified on the purchase specification as 46% or more. The maximum total power output of the
power facilities is calculated to be in the range of 73.8 to 108.8 MW.
Air temperature performance characteristics of the two CCGT models are shown below. From
this chart, it is evident that each CCGT has similar output characteristics.

As representative CCGT models using GTs of aircraft conversion types and those of
heavy-structural industrial types, LM6000PD Sprint and H-25 were chosen to show below the
heat balance diagrams under the rated CCGT site conditions and the maximum capacity CCGT
site conditions.

1) Heat Balance Diagram of 2 x LM6000PD Sprint at the rated site conditions

2) Heat Balance Diagram of 2 x LM6000PD Sprint at the maximum capacity site conditions
3) Heat Balance Diagram of 2025(2 x H-25) at the rated site conditions
4) Heat Balance Diagram of 2025(2 x H-25) at the maximum capacity site conditions

140
LM6000PD Sprint
LM6000PD
120
H-25
RB211-GT61
100
Net Power Output (MW)

80

60

40

20

0
0 5 10 15 18 20 25 28 30 35 40 45 50
Ambient Temperature (C)

(Source: JICA Study Team)

Figure6.2-1 Ambient Temperature Performance Characteristics Curve

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117.3 T

GROSS POWER OUTPUT

GT : 41,477 kW x 2
ST : 25,881 kW
PLANT GROSS POWER OUTPUT
Pre-heater
108,835 kW
AUX. P OWER 2,288 kW Deaerating Heater
PLANT NET POWER OUTPUT
106,547 kW

PLANT NET THERMAL EFFICIENCY 51.4 % 11.9 P

PLANT GROSS THERMAL EFFICIENCY 52.5 % 49.2 T
LP BFP
0.034 G
OPERATING CONDITION LP 665.6 P 2,311.0 H
o LP Eva
AIR TEMP ( C) 28.0 148.1 T
AIR PRESS (kPa) 101.30 15.736 G
RH (%) 75.0 623.0 H HP BFP
TYPE OF FUEL Natural Gas BLOW
LHV (kJ/kg) 47,597
HP Eco 0.091 G
7806.1 P 587.9 P
NOTE 159.2 T 158.0 T
1. Gross power output is defined at generator terninals. 11.458 G 11.458 G
676.0 H 667.0 H
2. All performance figures indicated in this diagram are
LP SH SPRAY WATER
preliminary values on new and clean conditions of equipment.

P : kPa 529.1 P
o From Other HRSG
T: C 251.1 T
HP
G : kg/s HP Eva 7194.1 P 4.133 G
H : kJ/kg 270.6 T 2,962.0 H
11.243 G 529.1 P
Demi Water 1,187.0 H 500.0 P 251.1 T
From Other HRSG
Steam B LOW 6471.6 P 250.0 T 4.133 G
Gas (Air) 0.220 G 431.8 T 9.404 G 2962.0 H
11.238 G 6000.0 P 2,962.0 H
3250.0 H 429.0 T
22.475 G
HP SH DeSH
3,251.0 H

2.20 G
6471.6 P
431.8 T
11.238 G FUEL
COMBUSTOR
3,250.0 H

GENETATOR
104.0 P
464.0 T GAS COMP STEAM TURBINE
122.280 G TURBINE
491.9 H
11.9 P 739.6 P
49.2 T 49.2 T
30.740 G 31.470 G
2,311.0 H 206.0 H
AIR
AIR COOLED
101.3 P CONDENSER
28.0 T FROM STEAM
TURBINE
GLANDS

Heat and Mass Balance Diagram

of 2 on 1 Configuration Combined Cycle Power Plant
on Ambient Temperature Conditions of 28 ℃
with Forced Draft Air Cooled Condenser
Type of Gas Turbine : IHI LM6000PD Sprint CONDENSATE PUMP GLAND STEAM
CONDENSER

(Source: JICA Study Team)

Figure 6.2-2 Heat Balance Diagram of 2 x LM6000PD Sprint at the rated site conditions performance

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111.2 T

GROSS POWER OUTPUT

GT : 47,383 kW x 2
ST : 29,442 kW
PLANT GROSS POWER OUTPUT
Pre-heater
124,207 kW
AUX. P OWER 2,461 kW Deaerating Heater
PLANT NET POWER OUTPUT
121,746 kW

PLANT NET THERMAL EFFICIENCY 52.8 % 4.7 P

PLANT GROSS THERMAL EFFICIENCY 53.9 % 31.8 T
LP BFP
0.040 G
OPERATING CONDITION LP 665.6 P 8.5 P 2,214.0 H
o LP Eva
AIR TEMP ( C) 10.0 148.1 T 42.6 T
AIR PRESS (kPa) 101.30 16.396 G 0.696 G
RH (%) 75.0 623.0 H 178.0 H HP BFP
TYPE OF FUEL Natural Gas BLOW
LHV (kJ/kg) 47,597
HP Eco 0.103 G
7806.1 P 587.9 P
NOTE 159.2 T 158.0 T
1. Gross power output is defined at generator terninals. 11.534 G 11.534 G
676.0 H 667.0 H
2. All performance figures indicated in this diagram are
LP SH SPRAY WATER
preliminary values on new and clean conditions of equipment.

P : kPa 529.1 P
o From Other HRSG
T: C 251.1 T
HP
G : kg/s HP Eva 7194.1 P 4.700 G
H : kJ/kg 270.6 T 2,962.0 H
11.534 G 529.1 P
Demi Water 1,187.0 H 500.0 P 251.1 T
Steam B LOW From Other HRSG 6471.6 P 250.0 T 4.700 G
Gas (Air) 0.226 G 425.2 T 9.404 G 2,962.0 H
11.308 G 6000.0 P 2,962.0 H
3,233.0 H 422.4 T
22.616 G
HP SH DeSH
3,234.0 H

2.43 G
6471.6 P
425.2 T
11.308 G FUEL
COMBUSTOR
3,233.0 H

GENETATOR
104.0 P
448.0 T GAS COMP STEAM TURBINE
133.913 G TURBINE
469.5 H
4.7 P 739.6 P
31.8 T 31.9 T
32.021 G 32.800 G
2,214.0 H 134.0 H
AIR
AIR COOLED
101.3 P CONDENSER
10.0 T FROM STEAM
TURBINE
GLANDS

Heat and Mass Balance Diagram

of 2 on 1 Configuration Combined Cycle Power Plant
on Ambient Temperature Conditions of 10 ℃
with Forced Draft Air Cooled Condenser CONDENSATE PUMP GLAND STEAM
CONDENSER
Type of Gas Turbine : IHI LM6000PD Sprint

(Source: JICA Study Team)

Figure 6.2-3 Heat Balance Diagram of 2 x LM6000PD Sprint at the maximum capacity site conditions

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106.2 T

GROSS POWER OUTPUT

GT : 23,961 kW x 2
ST : 25,870 kW
PLANT GROSS POWER OUTPUT
Pre-heater
73,792 kW
AUX. P OWER 1,485 kW Deaerating Heater
PLANT NET POWER OUTPUT
72,308 kW

PLANT NET THERMAL EFFICIENCY 46.8 % 13.9 P

PLANT GROSS THERMAL EFFICIENCY 47.8 % 52.5 T
LP BFP
0.029 G
OPERATING CONDITION LP 665.6 P 2,369.0 H
o LP Eva
AIR TEMP ( C) 28.0 148.1 T
AIR PRESS (kPa) 101.30 13.812 G
RH (%) 75.0 623.0 H HP BFP
TYPE OF FUEL Natural Gas BLOW
LHV (kJ/kg) 47,597
HP Eco 0.047 G
7806.1 P 587.9 P
NOTE 159.2 T 158.0 T
1. Gross power output is defined at generator terninals. 11.705 G 11.705 G
676.0 H 667.0 H
2. All performance figures indicated in this diagram are
LP SH SPRAY WATER
preliminary values on new and clean conditions of equipment.

P : kPa 529.1 P
o From Other HRSG
T: C 251.1 T
HP
G : kg/s HP Eva 7194.1 P 2.011 G
H : kJ/kg 270.6 T 2,962.0 H
11.461 G 529.1 P
Demi Water 1,187.0 H 500.0 P 251.1 T
From Other HRSG
Steam B LOW 6471.6 P 250.0 T 2.011 G
Gas (Air) 0.225 G 502.8 T 4.022 G 2962.0 H
11.481 G 6000.0 P 2,962.0 H
3424.0 H 500.0 T
22.961 G
HP SH DeSH
3,422.0 H

1.62 G
6471.6 P
502.8 T
11.481 G FUEL
COMBUSTOR
3,424.0 H

GENETATOR
105.3 P
562.0 T GAS COMP STEAM TURBINE
85.169 G TURBINE
605.4 H
13.9 P 739.6 P
52.5 T 52.6 T
26.983 G 27.624 G
2,369.0 H 220.0 H
AIR
AIR COOLED
101.3 P CONDENSER
28.0 T FROM STEAM
TURBINE
GLANDS

Heat and Mass Balance Diagram

of 2 on 1 Configuration Combined Cycle Power Plant
on Ambient Temperature Conditions of 28 ℃
with Forced Draft Air Cooled Condenser CONDENSATE PUMP GLAND STEAM
CONDENSER
Type of Gas Turbine : Hitachi H-25

(Source: JICA Study Team)

Figure 6.2-4 Heat Balance Diagram of 2 x H-25 at the rated site conditions performance

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95.9 T

GROSS POWER OUTPUT

GT : 26,866 kW x 2
ST : 29,715 kW
PLANT GROSS POWER OUTPUT
Pre-heater
83,447 kW
AUX. P OWER 1,565 kW Deaerating Heater
PLANT NET POWER OUTPUT
81,882 kW

PLANT NET THERMAL EFFICIENCY 49.7 % 5.6 P

PLANT GROSS THERMAL EFFICIENCY 50.6 % 34.8 T
LP BFP
0.032 G
OPERATING CONDITION LP 665.6 P 2,268.0 H
o LP Eva
AIR TEMP ( C) 10.0 148.1 T
AIR PRESS (kPa) 101.30 14.352 G
RH (%) 75.0 623.0 H HP BFP
TYPE OF FUEL Natural Gas BLOW
LHV (kJ/kg) 47,597
HP Eco 0.005 G
7806.1 P 587.9 P
NOTE 159.2 T 158.0 T
1. Gross power output is defined at generator terninals. 12.069 G 12.069 G
676.0 H 667.0 H
2. All performance figures indicated in this diagram are
LP SH SPRAY WATER
preliminary values on new and clean conditions of equipment.

P : kPa 529.1 P
o From Other HRSG
T: C 251.1 T
HP
G : kg/s HP Eva 7194.1 P 2.181 G
H : kJ/kg 270.6 T 2,962.0 H
11.811 G 529.1 P
Demi Water 1,187.0 H 500.0 P 251.1 T
From Other HRSG
Steam B LOW 6471.6 P 250.0 T 2.181 G
Gas (Air) 0.231 G 502.8 T 4.022 G 2962.0 H
11.838 G 6000.0 P 2,962.0 H
3424.0 H 500.0 T
23.675 G
HP SH DeSH
3,422.0 H

1.73 G
6471.6 P
502.8 T
11.838 G FUEL
COMBUSTOR
3,424.0 H

GENETATOR
105.3 P
556.0 T GAS COMP STEAM TURBINE
90.176 G TURBINE
592.4 H
5.6 P 739.6 P
34.8 T 34.9 T
28.038 G 28.703 G
2,268.0 H 146.0 H
AIR
AIR COOLED
101.3 P CONDENSER
10.0 T FROM STEAM
TURBINE
GLANDS

Heat and Mass Balance Diagram

of 2 on 1 Configuration Combined Cycle Power Plant
on Ambient Temperature Conditions of 10 ℃
with Forced Draft Air Cooled Condenser CONDENSATE PUMP GLAND STEAM
CONDENSER
Type of Gas Turbine : Hitachi H-25

(Source: JICA Study Team)

Figure 6.2-5 Heat Balance Diagram of 2 x H-25 at the maximum capacity site conditions

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(4) Trend of 30-40 MW-class GTs

According to the development of refractory metal of GT blades and nozzles, cooling technology for
blades and nozzles and the application of thermal barrier coating to hot gas parts and the increase
of air compression ratios, gas turbines output and thermal efficiency are increasing daily by GT
manufacturers. The 30– 40 MW class GTs are being developed, too. Table 6.2-3 shows the 30-40
MW class new GT models in the most recent order. These GTs have not yet been installed.
Attention must be paid to that these GTs installations around the world.

Table 6.2-3 New Models for 30 – 40 MW

Efficiency
Manufacturer Model Output Year
(LHV)
Kawasaki L30A 30.1MW 40.1% 2012
Siemens SGT-750 35.9MW 38.7% 2012
Rolls-Royce RB211-H63 42.5MW 39.3% 2012
(Source: Kawasaki brochure, and 2012 GTW Handbook)

6.2.2 Exhaust Gas Bypass System

In the case of a multi-shaft CCGT, the exhaust gas bypass system is usually equipped for a simple
cycle operation due to many factors which may occur to the bottoming system. This system will
also be required when the GT power package of topping system must be put into commercial
operation in advance separately from the bottoming system due to any impending power demand,
like in the Mozambique case. For this purpose, a bypass stack and a damper must be equipped in
the high temperature gas stream between the GT exhaust system and the heat recovery steam
generator. This system must be of a huge shape of mechanical equipment to cope with high
temperatures around 500C. Therefore, the system has the advantage of contributing to flexible
operation, although the plant cost is higher with lower operational reliability. Besides, performance
loss may occur by leakages of GT exhaust gas into the atmosphere. Such issues are studied below.

(1) Operational Flexibility

The operational flexibility of the CCGT changes depending upon whether or not there is an exhaust
gas bypass system. In the case the CCGT has the exhaust gas bypass system, the plant can be
transferred to simple cycle operation without power failure when any trouble occurs with the
bottoming system. The unit downtime can be reduced as inspections of and repairs to the bottoming
cycle can be undertaken while operating the GT. Such operation may be confined to limited hours
because it is not deemed to be of normal operation. As stated above, the operational flexibility of
the plant shall be limited if it does not have the exhaust gas bypass system.

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There are no differences between plants with and without the exhaust gas bypass system as far as
the start-up capability of the plant is concerned.

(2) Operational Reliability

Diverter or flap type dampers are normally utilized for GT applications with heat recovery steam
generators. The temperature of the exhaust gas to which the damper is exposed is as high as 500C.
The damper shall be designed to stably, smoothly and quickly operate, and to maintain minimized
gas leakage loss over the lifetime of the plant. It appears to be significantly difficult to design the
damper to operate under such severe conditions so that it can fully meet such contradictory
requirements. One reason is because the huge metal constructed damper which will be exposed to
high temperature atmosphere cannot keep the originally dimensioned shape over the lifetime of the
plant. Specific figures on the operational reliability of the exhaust gas bypass system by users of
the plants are not available. However, a decrease in the plant operational reliability due to using the
system is inevitable.

(3) Cost Impact

In order to use the exhaust gas bypass system, the following equipment and work are additionally
required:

 A bypass stack (3.3 m summit diameter, 28 m height) with a silencer (depending upon
environment protection requirements)

 A diverter damper

 A guillotine damper (for maintenance of the bottoming system during the simple cycle
operation)

 Longer transition gas ducts and expansion joints

 Related site assembly, erection and civil work

 Other related costs such as shipping, management and commissioning

The total extra cost for the above items is approximately estimated at US$ 2.0 million.

(4) Phased Construction

If the exhaust gas bypass system is used, there will be phased construction of the topping and
bottoming systems. Using this system will enable operation of the GT power generation facility to
start earlier. This type of construction will usually be adopted when power supply is demanded
earlier due to an unexpectedly steep increase of power demand. The completion schedule of the
phased construction plant is longer than the single phase construction plant, while the commercial

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operation of the GT/generator package will start earlier by approximately six months. This
advantage shall be evaluated by the plant purchaser depending upon the extent of the strong
demand for power supply.

(5) Performance
Excess exhaust pressure loss will occur due to the installation of the bypass system between the GT
exhaust and the heat recovery steam generator. Moreover, there will be an amount of exhaust gas
leaked into the atmosphere through the bypass damper, which will result in power loss of the steam
turbine. Consequentially, both the plant power output and efficiency will be lower in comparison
with plants that do not have the bypass system. Depending upon the type, size and system design of
the damper, the steam turbine power output drop is reportedly approximately 0.5 – 1.5% as an
average value over the lifetime of the plant. It means that the plant efficiency drops by 0.17 – 0.5%.

(6) Other Viewpoints

A wider footprint area is required for the installation of the bypass system. In the case of F-class
GTs, an additional 9 m in length would be required.
In the case that there is no silencer in the bypass stack, the noise from the stack is a concern even if
the bypass operations will be limited to a short time.

In the case that a silencer is installed in the bypass stack, the steady and proper function over the
plant lifetime of the silencer, which is exposed to high temperatures and high velocity of gas, is a
concern. Additional deliberate and daily maintenance work is required to maintain the exhaust gas
bypass system in good condition so that it can be reliably used whenever it is needed. There are
many CCGTs using exhaust gas bypass facilities worldwide.

(7) Study Summary

A summary of the results of the evaluation is shown in the following table. As stated above, it goes
without saying that the operational flexibility of the plant will be enhanced due to the employment
of the exhaust gas bypass system, however there is the inevitable drop in operational reliability plus
the burden of project cost. Because of the large volume of exhaust gas, high temperatures and
speed, broad working experience is necessary in order to operate and maintain the exhaust gas
bypass system in good condition. However, this CCGT will be the first CCGT in Mozambique.
Therefore, in order to operate CCGT to maintain good condition with high output, high efficiency
and minimum trouble outage, a CCGT without the exhaust gas bypass system is recommended.

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Table 6.2-4 Summary of GT Exhaust Gas Bypass System

Review Items Without Bypass System With Bypass System

1. Operational Flexibility GT single operation impossible GT single operation possible

Low
The constructed damper, which will
Base be exposed to high temperature
2. Operational Reliablity
atmospheres, cannot keep the
originally dimensioned shape over the
lifetime of the plant.

Base
Construction cost not necessary +Approx. USD 2M for facility and
3. Cost Impact construction
Operation & maintenance cost not Operation & maintenance cost
necessary necessary
Base
4. Footprint Necessary for the facility
Unnecessary
5. Phased Construction Impossible Possible
0.17 - 0.5% lower
6. Performance
Base due to increase of exhaust pressure
(Thermal Efficiency)
loss and leakages of GT exhaust gas
Maintenance and operation
7. Other Base
experience necessary.

(Source: JICA Study Team)

6.2.3 Auxiliary Boiler

(1) Necessity
In the case of a multi-shaft CCGT without a standalone auxiliary boiler, the GT can be started up
together with the HRSG separately from the steam turbine/generator. After a certain period of time
the necessary steam for start-up will become available from its own HRSG and then the steam
turbine/generator can be started up under its own steam; however the HRSG will be started up with
a higher oxygen concentration in the HRSG inlet feed water than under normal operating
conditions because of the start up without gland sealing of the steam turbine.

In the case of multi-shaft CCGT with a standalone auxiliary boiler, gland sealing of the steam
turbine can be supplied from external sources before the GT and HRSG are operated. As the
necessary steam for start-up can become available from external sources, the steam
turbine/generator can be started up without any loss of time and the HRSG can be started up within
permissible oxygen concentration in the HRSG inlet feed water by gland sealing of the steam

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turbine.

If a standalone auxiliary boiler is applied to this project, then the tender shall recommend the
specifications for a standalone auxiliary boiler.

(2) Requirement Study

The HRSG and auxiliary equipment shall be designed to be able to start up in the shortest time.
If a standalone auxiliary boiler is not applied to this project, the tender shall clarify the start up
procedure without a standalone auxiliary boiler and the start up time schedule, and the operating
and permissible oxygen concentration in the HRSG inlet feed water during start up.

6.2.4 Gas turbine and steam turbine buildings

The GT and steam turbine buildings will protect the facilities from rain, wind and salt from the sea,
and prevent facility deterioration due to rust, etc., and enable personnel to carry out maintenance
and management work without any effects from the climate, either during the day or at night.
However, the buildings will need to have air-conditioning, fire-resistance and other facilities, and
the related maintenance costs.

A review of the GS and steam turbine buildings was conducted, and the characteristics of the GT
and steam turbine facilities with or without buildings are shown in the table below:

Table 6.2-5 GT and Steam Turbine Facilities With and Without Buildings

Review Items Without Building With Building

Building facility Base ･Building
・Electrical wiring, air-conditioning facility,
lighting, etc.
･Overhead traveling crane
･Fire/ smoke sensors
･Fire protection facility
Building facility
Base High
costs
Running costs Base High
･ Periodical inspection of overhead
traveling crane, fire protection facility,
etc.
Operability Base Good
･No influence from wind, rain and sea
water
Maintainability Base Good
･ Need to prepare a crane every ･Repair work is always possible in the case
work time. of problems as an overhead traveling

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Review Items Without Building With Building

･Bad workability at night. crane will be installed.

･Repair work may be impossible due ･Workable at night.
to bad weather. ･No influence from the weather.
･ Not workable if flooding and ･ Workable even if flooding and
submergence occur. submergence occur.
Equipment Base Rust can be prevented from seawater, etc.
facility
Noise Base Small
Facility
Base High
reliability
(Source: JICA Study Team)

(1) Gas Turbine Building

Case by case, GTs are installed either indoors or outdoors. Outdoor GT power generators are
packaged and there are many working examples in the world. The existing GT No. 3, which is also
an outdoor type, is approximately 20 years old however it is maintained in good condition. The GT
is covered with a compartment, thus offering sufficient durability against the weather. Plant output
and efficiency undergo little impact from rain, etc. For the GT power generator, from the viewpoint
of broad experience and economics, an outdoor type without a GT building is recommended.

(Source: GE brochure)

Figure 6.2-6 GT Package

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(2) Steam Turbine Building

The output and efficiency of a steam turbine are influenced by the steam temperature and pressure.
To reduce lowering the steam temperature and pressure, thick thermal insulating materials are
applied to the casing and the piping. Rainwater, water, and seawater going inside the insulating
materials lowers the steam temperature and pressure, and deteriorates the thermal insulating
materials, steam turbine casing, piping, valves and other components. To operate the steam turbine
in good condition for a long period of time, the casing, piping and valves need to be protected from
the influence of water and, therefore, it is recommended that the steam turbines be installed
indoors.

6.3 Scope of Work

6.3.1 Procurement and/or Manufacture

The contractor shall procure and manufacture the following facilities, including progress control
and quality control, with regard to all the equipment and materials related to operation, etc. Note,
however, that the facilities to be procured and manufactured may not be limited to the following
facilities.

(1) GT power generators and related facilities

(2) Steam turbines, power generators and related facilities
(3) Air cooled condenser and related facilities
(4) HRSGs and related facilities
(5) Stacks
(6) Fuel gas accepting facility
(7) Fuel gas pipe line (from tie-in point of gas station to compressor or decompression facility)
(8) Fuel gas compressor or decompression facility (if necessary)
(9) Gas treatment facility (if necessary)
(10) Indirect gas warmer (if necessary)
(11) Inside and control air supply facilities
(12) Generator step-up transformer
(13) Auxiliary transformers
(14) Switch gear for generator
(15) Modify 66kV GIS

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(16) Middle and low voltage power supply devices

(17) Emergency generators
(18) UPS and DC power supply devices
(19) Cables (electric power, instrumentation and control (“I&C”) )
(20) Cable trays and duct facilities
(21) Control and instrumentation facilities
(22) Facility information system
(23) Continuous environmental monitoring facility
(24) Simple simulator facility
(25) Drain recovery facility
(26) Bearing coolant facility
(27) Water facility and wastewater treatment equipment
(28) Outdoor piping, trenching and covering
(29) Fire protection facility
(30) Ventilation and air conditioning facilities
(31) Outdoor and indoor lighting
(32) Outdoor drainage and clarification facility
(33) Piping and facility foundation
(34) Construction materials
(35) Steam turbine building (steel frame, exterior, roof, windows, louvers, etc.)
(36) Buildings for other facilities
(37) Office building (including central control room and electricity room)
(38) Workers’ living quarters
(39) Restrooms and shower rooms
(40) Roads
(41) All civil works including foundations for supplied equipment, buildings and houses
(42) Temporary structure construction and facilities related to construction
(43) Preparation, excavation and leveling work of site area including temporary storage area
during construction and preparation of access road for transporting-in heavy components
(44) Fencing around the new plant site, access road to stored equipment, and drainage inside the
new plant site
(45) Necessary temporary facilities on the downstream side from the connection points of utilities
such as electric power and water, etc., necessary for construction
(46) Paint/coating materials for equipment and materials

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(47) Spare parts for periodical repair

(48) Standard and special tools

6.3.2 Works and Services to be provided by Contractor

The construction and work scope that the contractor shall execute shall include the design of a new
CCGT including modification of the existing switching station, etc., manufacture of equipment,
and tests, transportation, installation, construction, trial operation and performance tests thereof.
In the case where such words as “provide”, “furnish”, “supply”, and “furnish and/or install” are
used, the contractor shall install equipment and facilities even if the equipment and facilities
installed by another party have no special safety features.

The construction scope of the contractor shall include the preparatory construction in the early
phase including the power supply for construction, the construction of temporary facilities for trial
operation and tests that are necessary for the operation of the power generation facility, and the
construction of the permanent facilities.

The work scope of the contractor shall include technical instructions to the sub-contractors and the
equipment suppliers so that the operation of the power generation facility can be commenced in
addition to the training of the operation and maintenance personnel of the newly-installed power
generation facility.

In cooperation with the CTM CCGT operation personnel, the contractor shall start the
newly-installed power generation facility and execute early-phase operation thereof. The contractor
shall instruct the new operation personnel of the CTM CCGT and, in cooperation with the same
personnel, plan smooth technical instructions from construction of the newly-installed power
generation facility to commencement of operation thereof. Note that any additional construction
and work items shall require agreement by contract.

(1) Engineering services

1) Engineering and structural facilities
2) Architectural facilities
3) Mechanical facilities
4) Chemical facilities
5) Electrical facilities

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6) Control and instrumentation

7) Switching station facilities
8) Power flow calculation for electrical facilities

(2) Documents and drawings

The newly-installed power generation facility shall be equipped with all equipment provided in this
section. The work items provided in the purchase specifications may not be limited to the creation
of the below-listed design documents. The asterisked documents are those that shall be submitted at
a minimum for the approval of EDM. If the asterisked documents are submitted, all other
documents and drawings shall be submitted as reference. Within thirty days from commencement
of construction, the contractor shall submit a list of drawings and documents on which the
documents for approval and those for reference shall be distinguished from each other.

*1) Facility design criteria

*2) Premises layout
*3) Floor-by-floor equipment layout
*4) Heat balance diagrams
*5) Skeleton diagrams
*6) Facility piping and measurement drawing
*7) Building front view and elevation
*8) Entire plant control block diagram
*9) Purchase specifications:
- GT
- Steam turbine
- HRSG
- Air-cooled condenser
- Feed and condensate pumps
- Power generator and exciting arrangements
- Transformers (generator step-up, auxiliary and start up transformers)
- Middle-pressure metal clad switch gear
- Dispersed control system (“DCS”) and data storage unit
10) Concrete foundation and structure drawings
11) Purchase specifications of major equipment

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12) Design study and evaluation

13) Detailed designs
14) Logic diagrams
15) System diagrams
16) Wiring diagrams
17) Facility instruction manuals
18) Test and inspection schedule
19) Performance test instructions
20) Trial operation instructions
21) Test and inspection report
22) Performance test report
23) Operation manual
24) Maintenance manual
25) Equipment manuals (including catalogs)
26) Installation instructions
27) Complete documentation

(3) Construction and trial operation

The contractor shall execute the following work items with regard to construction and trial
operation of the newly-installed power generation facility. Note, however, that the work items in
the construction and trial operation phases may not be limited thereto.

1) Supervision of construction
2) Management of construction schedule
3) Preparation and control of construction workers and preparation of tools to be used by them
4) Preparation of construction machines
5) Safety and loss control program
6) Quality assurance program
7) Procurement promotion assurance
8) Receiving, handling and storing devices and materials
9) Preparation condition check, tests, start up and trial operation
10) Supplying lubricants necessary for start up, tests and operation in the early phase and chemicals
necessary for water treatment and chemical analyses

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11) Supplying lubrication devices and lubricants for flushing and filling in the early phase
12) Performance and reliability tests
13) In-factory and on-site training of operation/maintenance personnel from EDM
14) Support supervision of operation and maintenance for six months after the acceptance test by
three engineers resident on site (i.e., mechanical, electrical and control)
15) Completion of construction and finish of site
16) Construction of a storage warehouse
17) Safety and medical aid during construction
18) Participating in arrangement meetings required by CTM CCGT and other meetings
19) Payment of lodging expenses, wages and traveling expenses with regard to factory tests and
inspections
20) Obtaining local, provincial and national approvals and authorizations necessary for
construction of the newly-installed power generation facility

(4) Participating in design meetings

In order to appropriately execute the designing of the newly-installed power generation facility, it
is recommended that three or more meetings be held with EDM, the contractor and the consultant
during the project period. These meetings shall be held so that the documents submitted by the
contractor for approval can be checked and discussed in an efficient and effective manner.

The period of each design meeting shall be within every four weeks. The meeting shall be
separated into four or more working groups including engineering, mechanical, electrical and
instrumentation/control working groups. The meetings shall be held in those periods that are
effective for promotion of the project in conformity with the contract between EDM and the
contractor.

All the documents and drawings to be discussed at each design meeting shall be submitted to EDM
at least one month prior thereto. The contractor shall participate in the meetings at its own expense.
To obtain the approval of EDM and the consultant, the contractor shall, within one month after
commencement of work, submit a list of participants, a list of discussion items, detailed schedule
documents and a list of drawings, as well as a design meeting schedule with regard to the
requirements from EDM. If it is determined that an interpreter is necessary at the design meetings,
the contractor shall prepare an interpreter at its own expense. To complete the CTM CCGT as

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scheduled, EDM will review and supervise the contractor’s designs and construction and, if
necessary, make the contractor execute changes, improvements and amendments. Any changes in
the contract amount for these design changes shall require the mutual consent of EDM and the
contractor.

6.3.3 EDM’s construction work and work items

EDM will execute the following construction work and work items with regard to the
newly-installed power generation facility:

(1) Supplying drinking water, warm water, natural gas and electric power during construction
(2) Supplying power for start up and auxiliary steam
(3) Preparing an environment assessment
(4) Supporting the obtainment of all approvals and authorizations necessary for the construction
and operation of the newly-installed power generation facility
(5) Offering information on natural gas and electric power loads for trial operation and
assurance and reliability tests
(6) Evaluation of the periodical items of the operation and maintenance data and information
during the two-year guarantee period and operation and maintenance conditions
(7) Preparation of on-site manpower, facilities and tools with regard to inspection to be executed
after the expiration of the guarantee period
(8) Removal of the existing oil tanks and relocation of power cables for existing No.3 Gas Turbine

6.3.4 Terminal Points

For the water terminal point, the piping will be split in the vicinity of the booster pump. As the
detailed location is not decided yet, it shall be reviewed and decided by EDM and ÃGUAS da
REGIÃO de MAPUTO. As to the fuel gas terminal point, because how to draw from the gas station
to the power plant side is not decided, too, it shall be discussed and decided by EDM and Empresa
Nacional de Hidrocarbonetos de Moçambique (“ENH”). The electrical cables shall be added and
connected in the vacant space in the existing switching station.

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Portable
Wate r Tie- in
point

New Gas Gas Tie- in

Station point

66 kV Tie -in
point

CCGT Contraction Area

Contraction
Spare Are a

(Source: JICA Study Team)

Figure 6.3-1 Terminal Point

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6.4 Plant Design Considerations

6.4.1 Design conditions

The CTM CCGT shall be designed in accordance with the below-listed design conditions:

Table 6.4-1 Design conditions

Design air temperature (dry-bulb)/ relative humidity

28°C/ 75%
(performance guarantee point)
Design minimum air temperature (dry-bulb)/ relative
10°C/ 75%
humidity (generator maximum capacity point)
Minimum/ maximum relative humidity 60%/ 95%
Minimum air temperature (dry-bulb)/ maximum air
9°C/ 43°C
temperature (dry-bulb)
Atmospheric pressure 0.1013 MPa
Altitude E.L. + 3.3 m above M.S.L
UBC1997, Seismic Zone “2A”
Seismic criterion
Basic aseismic coefficient = 0.071g
Wind-resistant design (avg. of 10 min) 40 m/s
Annual average precipitation 800 mm
96.5mm/ hr
Maximum rainfall rate
(value of 1-hour continuation)
2
Snow load 0 kg/m
(Source: JICA Study Team)

6.4.2 Standards and Criteria

(1) Mechanical, electrical and control devices and equipment

Except for the items specially required in Mozambique, the CTM CCGT shall be designed in
conformity with the following international standards and criteria:

Japanese Industrial Standards (“JIS”)

US standards (ASME, ASTM, etc.)
IEC standards
ISO standards
British Standards (“BS”)
German standards (“DIN”)

(2) Engineering and construction work

Except in the case where specific standards and criteria shall be applied, engineering, designing and

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construction for the engineering and construction work shall be in conformity with the related standards
and criteria of Mozambique.

6.4.3 Site Layout

The CTM CCGT layout is planned as shown in Figure 6.4-1. For detailed drawings, see Attachment 1,
“Overall Project Plot Plan.” The considerations with regard to the layout of the major devices are as
listed below:
・ To reduce the effects of salt from the sea contained in the intake air, the air inlets of the gas
turbines will face the land side and will be laid out taking into consideration consistency with the
existing GTs No. 2 and No. 3.
・ Taking into consideration the power lines to the switching station and the transformer substation,
the power generators will be located on the north-western side in the premises so that the power
line routes to the switching station can be appropriate and short.
・ From the wind direction data, as it has been found that south-westerly winds frequently occur in
the summer, the thermal exchange facility for the air-cooled condenser, including the steam
turbine, will be located to minimize the effects of the air-cooled condenser to the GT intake air.
In addition, it will be located so as to be separate from the premises border on the north-eastern
side that touches the residential area.
・ To reduce the loss before the air-cooled condenser, the steam turbine will be located so as to
reduce the distance to the air-cooled condenser. Furthermore, the GT generators and HRSGs will
be located on the right side of the steam turbine. The steam turbine generator and the GT
generators will be installed indoors along with the related facilities for such purposes as noise
prevention.
・ The central control room, the electrical room and the battery room will be incorporated in the
office building.
・ The JICA Study Team has recommended to EDM that such facilities as the fuel gas facility and
the water and wastewater treatment facilities be located in the area of the existing No. 3 GT.
During the 2nd mission, EDM announced that the area of the existing No. 3 GT cannot be used
for the new CCGT. Following this, the CCGT layout was reviewed. By locating the fuel gas
pressure at the tie-in point required for CCGT, a fuel gas compressor or decompression facility
will be not necessary to be installed for this CCGT plant. Water and wastewater treatment
facilities will be installed in the area between the GT generator/ steam turbine generator and the
seaside boundary. If these related facilities cannot be installed in this area, these facilities will be
installed in the area between the existing No. 1/ No. 2 GTs and the seaside boundary.

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Ste am Tu rbin e
Ge n e rator

Gas Tu rbin e Tran sforme r

Ge n e rator

He at Re c ove ry
Ste am Ge n e rator
Air Coole d
Con de n se r
Ele c tric al Room &
Con trol Room

Waste Water
Tre atme n t Work Sh op
De min e ralize Wate r Plan t, Plan t
De min e ralize d Wate r Tan k &
Raw Wate r Tan k

(Source: JICA Study Team)

Figure 6.4-1 Plant Layout

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Stac k
Heat Recovery
Steam Gene rator

Gas Turbine

Gen erator

(Source: JICA Study Team)

Figure 6.4-2 Example of Gas Turbine and HRSG

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Gen erator Steam Turbin e Air Cooled

Con de nse r

(Source: JICA Study Team)

Figure 6.4-3 Example of Steam Turbine with Air Cooled Condenser

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6.4.4 Environmental Requirements

(1) Airborne Emissions

The plant exhaust emissions shall not exceed the emission limits specified in this project shown in
Table 6.4-2 based on the power output range of 75-100% of plant capacity with natural gas and
diesel oil firing.

Table 6.4-2 Emission Limits of Pollutants

Unit: mg/Nm3(0 ℃, 101.3 kpa)

Pollutant Emission Limits

NOx Gas-fired Below 320

CO Gas-fired 0.1 per day (< 500MW)

Particulates Gas-fired Below 50

Note: The above levels are based on 15% O2 dry conditions.

(Source: JICA Study Team)

(2) Noise Control

Ambient noise levels for all equipment operating under steady state conditions shall not exceed 85
dB(A) at a height of 1 m and a distance of 1 m from the edge of the equipment or the enclosure.
Equivalent noise levels at a height of 1 m on the power station boundary shall not exceed 70 dB(A).
Maximum noise levels for this project are summarized in Table 6.4-3.

Table 6.4-3 Noise Standards

Conditions Maximum Noise Levels

At 1m from the edge of the equipment or the enclosure Not more than 85 B(A)
At the power station boundary Not more than 70 B(A)
(Source: JICA Study Team)

All measurements of noise and testing shall be done in accordance with ANSI B133.8. To comply
with the above stated noise criteria, any modifications necessary, including the installation of
additional and/or improved sound attenuation equipment, shall be implemented.

(3) Treated Wastewater Quality

The treated wastewater discharge quality shall meet the standards in Table 6.4-4 World Bank and
Mozambique Standards for Effluents.

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Table 6.4-4 Effluent Standards

Mozambique
World Bank Standards (for
No. Parameter Unit
Standards Inland Surface
Water)
Ammoniacal Nitrogen
1. mg/l - 50
(N molecule)
2. Ammonia (free ammonia) ” - 0.4
3. Arsenic (As) ” - 0.05
4. BOD5 20oC ” - 50
5. Boron ” - 2
6. Cadmium (Cd) ” - 0.05
7. Chloride ” - 600
8. Chromium (total Cr) ” 0.5 0.5
9. COD ” - 200
10. Chromium (hexavalent Cr) ” - 0.1
11. Copper (Cu) ” 0.5 0.5
12. Dissolved Oxygen (DO) ” - 4.5 - 8
micro
13. Electrical Conductivity - 1,200
mho/cm
Total Dissolved Solids
14. mg/l - 2,100
(TDS)
15. Fluoride (F) ” - 7
16. Sulfide (S) ” - 1
17. Iron (Fe) ” 1 2
18. Total Kjeldahl Nitrogen (N) ” - 100
19. Lead (Pb) ” - 0.1
20. Manganese (Mn) ” - 5
21. Mercury (Hg) ” - 0.01
22. Nickel (Ni) ” - 1.0
23. Nitrate (N molecule) ” - 10.00
24. Oil & grease ” 10 10
25. Phenol compounds (C6H5OH) ” - 1.0
26. Dissolved Phosphorus (P) ” - 8
As determined by Mozambique Atomic Energy
27. Radioactive Materials
Commission
28. pH ” 6-9 6-9
29. Selenium mg/l - 0.05
30. Zn (Zn) ” 1.0 5.0
31. Total Dissolved Solids ” - 2,100
o
Summer C - 40
32. Temperature o
Winter C - 45
33. Total Suspended Solid (TSS) mg/1 50 150
34. Cyanide (CN) ” - 0.1
35. Total Residual Chlorine 0.2 0.01
o Less than or
36. Temperature increase C -
equal to 3*
Source: Pollution Prevention and Abatement Handbook, Word Bank Group, 1998
Schedule 10, Rule 13, Environment Conservation Rules
Note: *The effluents should result in a temperature increase of no more than 3oC at the edge of the zone where the initial
mixing and dilution take place. Where the zone is not defined, use 100meters from the point of discharge when there are
no sensitive aquatic ecosystems within this distance.

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(4) Environmental Monitoring Facilities

The Continuous Emission Monitoring System (”CEMS”) shall be installed to monitor flue gas from
the Plant. CEMS shall be required to monitor the amount of the flue gas and its concentrations of
NOx, Particulates and CO.

The continuous monitoring system for the amount of effluents from the wastewater treatment
system and its pH value and turbidity shall be monitored. The monitoring shall be conducted at the
treated water pit of the wastewater treatment system in the Plant.

6.4.5 Gas Turbine

The basic design functions required for the GT which will be employed for this project are
described herein. The GT shall be of an open cycle heavy duty or aero-derivative type. The GT
shall be supplied by an original equipment manufacturer. This CCGT will be the first CCGT in
Mozambique. Therefore, in order to operate CCGT to maintain good condition with high output,
high efficiency and minimum trouble outage, this CCGT shall be without the exhaust gas bypass
system.

In order to select a GT that satisfies this requirement from the 2-on-1 CCGTs having an output of
70 to 110 MW as described in the “Gas Turbine World 2012 GTW Handbook (Volume 29),” then
there are five models listed below as candidate GTs for this project:

Name of OEM Type of Model

IHI (GE licensed) LM6000PD Sprint
IHI (GE licensed) LM6000PD
Hitachi, Ltd. H-25
Rolls-Royce RB211-GT61
Siemens Power Generation SGT700

The GT power output shall be specified on the basis of continuous base load with the load
weighting factor of 1.0 for calculation of the equivalent operating hours (“EOH”), which will be a
scale of the inspection intervals of hot gas path parts.

The GT shall be operated with natural gas specified in Section 6.5.8, “Fuel supply facility.”
The GT shall be of an advanced design to meet the NOx emission requirement of less than 25 ppm

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(15% O2 basis of dry volume) for dry conditions for operation on specified natural gas under 75 –
100% load.

The GT shall be of proven design with manufacturer’s design practices to basically meet the
requirements of ISO 21789 Gas turbine applications – Safety.
The GT may be equipped with the evaporative type inlet air cooling system to augment the GT
power output. According to climate data recorded for five years from 2007 to 2011 at Maputo
International Airport near CTM site, the temperature difference between average dry and wet bulb
temperatures is estimated at 3.5oC. This means that the GT inlet ambient temperature could be
decreased by at least 2.4oC utilizing the current widely-used evaporative cooling system. As a
result, the net power output may be increased by increasing fuel consumption.

The proposed GT shall be of a similar model to GTs, of which at least one GT has the experience
of successful commercial operation of not less than 6,500 hours of actual operating hours as of the
Bid closing date.

The GT design shall be with a minimum number of bearings, and shall be located on a steel frame
or on adequate steel structures and concrete foundation, sized for the transient maximum
transmittal torque imposed on the shaft in case of any short circuit of the generator or out-of-phase
synchronization, whichever is larger. The power output shall be taken out at the cold end of the
shaft.

The GT shall be directly coupled to the generator without any power transmission gear.

6.4.6 Heat Recovery Steam Generator

(1) Type of Circulation

HRSG could be of natural or forced circulation type. In natural circulation units, the thermal head
differential between water and steam-water mixture is responsible for the circulation through the
system. In forced circulation units, boiler circulating pumps (“BCPs”) circulate the steam-water
mixture through the tubes of the evaporator to and from the drum. Advantages claimed for forced
circulation design are their quick warm/ hot start up capabilities. However, natural circulation
designs do not need circulation pumps to maintain the circulation of steam-water mixture through
the evaporator tubes, thereby saving operating costs and relieving concerns about pump failure or
maintenance. The probability of the usage of natural circulation type HRSGs is higher because of

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the absence of the critical rotating equipment such as circulation pumps. There is no difference in
cold start up time periods due to the fact that in the transient heat up phase, the bulk of the time is
spent on heating the metal and water of the evaporator module, which is nearly the same whether it
is a natural or a forced circulation HRSG. In summary, both natural and forced circulations HRSGs
are widely used in the industry, while the natural circulation design has an edge over the forced
circulation design as discussed above. Hence the natural circulation types HRSG are proposed for
this project.

A comparison table (Table 6.4-5) for the type of HRSG circulation is provided for reference.

Table 6.4-5 HRSG Circulation Comparison

Item Natural Circulation Forced Circulation

1. Features Simple evaporator circuitry Complicated evaporator
without any pumps or valves circuitry with BCP and
valves
No auxiliary power Increase of BCP power
consumption consumption
Lower construction and Increased construction and
maintenance costs maintenance costs for BCP
and piping for water
circulation system
Simplified control, high Complicated control due to
reliability and availability (no BCP operation
load restrictions due to pump
failure)
There is no difference in start up time at cold start up between
both types

The time for natural Start up time at warm and hot

circulation start up is shorter than
force, start up time at warm natural circulation because
and hot start up is longer than circulation pumps are
forced circulation. applied.
2. HRSG Specification:
Heating surface: Base Same
Steel structure volume: Base Same
Boiler circulating pump
Not required To be provided (2 x 100%)
(BCP):
Stability of water: Base Same
Drum size: Base Same
Steam/ water side pressure Base Higher
drop:
(Source: JICA Study Team)

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(2) Flue Gas Flow Direction

HRSG is available for both horizontal and vertical flow directions. Vertical flow directional HRSG
occupy less floor space. Also, the HRSG forms part of the main stack and hence the main stack
requires less material. A comparison of both types of HRSGs is furnished in Table 6.4-6.

Table 6.4-6 Gas Flow Orientation Comparisons

Description Horizontal Gas Flow Type Vertical Gas Flow Type

Arrangement:
Installed Area Base Smaller
Distance from GT Outlet to Base Shorter
Stack Inlet
Height Base Same or a little higher
Taller stack is mandatory Independent higher stack is
Stack
not required
Circulation System Natural circulation system Natural or forced circulation
system
Heating Surface Support Top support system by Same
System hanger
(free to slide lower)
Operability Base Same
Maintenance and Inspection Base Easier for natural circulation
system but a little complex for
forced circulation system
Economics:
Equipment Cost Base A little higher
Operation Cost Base Same for natural circulation
system but higher for forced
circulation system
(Source: JICA Study Team)

(3) Conclusion
In view of the above reasons, HRSG of natural or forced circulation types are both acceptable for
this project. However, the natural circulation type HRSG is preferred.

With regard to flue gas flow direction, horizontal or vertical gas flow types are both acceptable for
this project. The flue gas flow direction will be decided based on the manufacturer’s
recommendation and the layout proposed during the contract stage, etc.

6.4.7 Steam Turbine

The steam turbine shall be a double-pressure, condensing type directly connected to the generator.
The steam shall be downward or axially exhausted to a surface condenser which is cooled by the
fresh circulating water, which is in turn cooled with a forced draft wet type cooling tower.

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The steam turbine shall be of the manufacturer's standard proven design and construction to allow
economical and reliable service with minimum maintenance work. The steam turbine to be
proposed shall be of similar design to the steam turbines of which at least one unit has the
commercial operation hours of not less than 6,500 hours as of the Bid closing time.

The steam turbine and auxiliary systems shall be designed to run continuously under all specified
operating conditions over the specified lifetime of the plant. The steam turbine maximum capability
shall satisfy the conditions of steam pressure, temperature, and flow as developed by the HRSG
when the GT is operated on maximum capability ambient conditions. In case that the HRSG is
supplementary fired, the steam turbine shall be sized to cope with the maximized capability of the
HRSG in consideration of the supplementary firing over the specified ambient conditions.

The steam turbine shall be designed so that the expected life expenditure of the main components
(casing and rotor) shall not exceed 75% of the expected lives of the components at the end of the
specified service hours when it will operate on specified conditions.
The steam turbine shall be provided with the necessary number of bore scope ports for easy
inspection of the operating conditions of the blades and rotor at periodical intervals, if applicable.

6.4.8 Fuel Supply System

The new plant shall be operated on the specified natural gas from Pande gas field. The GT shall be
designed to operate on the specified natural gas. The typical specifications are as shown in Table
6.4-7.
The fuel gas supply system shall cover all the equipment required for the start up, shut down and
continuous operation of the GT. A booster compressor station, a pre-treatment system, and a gas
pressure-regulating device shall also be included in the scope of the Contractor. The planned fuel
gas pressure is 25 bar at the tie-in point the near new gas station. If the tie-in point gas pressure
changes the CCGT requirements, it may not be necessary to install either a gas compressor or
decompress facility, and thereby service power may be reduced. The pre-treatment system shall be
facilitated to clean the specified gas to the extent that it will be used for the GT without any
difficulties. The specific energy (caloric value) is expressed on the conditions of 20°C of ambient
temperature and 101.3kPa of ambient pressure.

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Table 6.4-7 Gas Properties

Properties
Compositions (mol%)
Methane 90.823
Ethane 3.452
Propane 1.732
Normal Butane 0.535
Isobutane 0.449
Normal Pentane 1.212
Isopentane 0.152
Normal hexane 0.172
Normal heptane 0.066
Normal octane 0.0018
Nonane 0.0002
Oxygen 0.027
Nitrogen 2.454
Carbon Dioxide 0.001
Hydrogen Sulfide 0
Total 100.0
Hydrogen Sulfide (g/ m3) 0.000
Specific Energy (kJ/kg)
Gross specific energy 52,735
Net specific energy 47,562
Specific Gravity (kg/m3N) 0.8056
Min. 9°C
Temperature (°C) Max. 43°C
Performance point 28°C
Pressure at Tie-in point (bar) 25
(Source: EDM)

6.4.9 Water Treatment System

Processed water such as demineralized water, drinking water, clean water, water for fire-fighting,
and water for miscellaneous use, will be split from the water piping at the entrance of the CTM
Power Plant and produced, if necessary, by use of a pretreatment system.
The demineralized water will be used for supplying make-up water to the HRSGs, cooling of the
GT intake air, cooling of the auxiliary machinery, and water supply for chemical injection.
The EPC Contractor shall confirm the quality of the produced demineralized water and whether it
is acceptable to the HRSG. The pre-treatment system will consist of coagulators and filters, etc.
The demineralizer system will consist of chemical storage and regeneration equipment, etc. The
necessity and specification of the pre-treatment system will be decided based on the quality of the
ground water. The EPC Contractor shall take appropriate countermeasures if required. The
conceptual flow diagram is shown in Figure 6.4-4 “Water Mass Balance Diagram”.

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Stream No. ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ⑩ ⑪ ⑫ ⑬ ⑭ ⑮ ⑯

Flow (㎥/h) 30 2 10 10 9 9 1 18 13 1 8 5 3 3 5 5

Water Make up
Source

① ②
Control &
Office Building

Pretreatment
System
④ ⑤ ⑥ ⑦
③ Demineralizer Demineralized
HRSG Make up
System Water Storage
Water
Tank Blow down
Raw Water
Storage Tank
⑪
To atmosphere
⑩
⑨ GT Compressor
⑧ Inlet air Cooling
Auxiliary Cooling
Water Chiller
Water System
To atmosphere

From Transformer/ ⑬ ⑭ ⑮ Wastewater ⑯ Sea

Switch Yard Area Oil Separator Settling Basin Treatment
Drain System

(Source: JICA Study Team)

Figure 6.4-4 Water Treatment Flow (Water Balance)

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6.4.10 Wastewater System

Wastewater shall consist of neutralized regeneration waste from HRSG blow down, floor drains from
the GT and steam turbine buildings, and contaminated yard drains from the transformer area. Sewage
and sanitary wastewater shall be treated in the purifying facility. Floor drains from the GT and steam
turbine buildings and contaminated yard drains from the transformer area shall be treated in the oil/
water separators. After treatment, these clean wastewater streams shall be discharged through the main
drainage pipe into Maputo bay.

6.4.11 Fire Fighting System

(1) Fire safety philosophy

The CTM CCGT will be designed and built with the provision of a safe operating environment and
safe working personnel. This will be achieved by separation and segregation of equipment with
sufficient distance between and by the selection of suitable equipment and materials.

Hazardous areas will be designated and suitable equipment will be selected for use in these areas.
Different fire fighting systems will be installed depending on the operational characteristics of the
equipment, area and buildings to be protected. The fire fighting capacity of the CTM CCGT must be
able to withstand a of two hour fire according to NFPA 850 with a minimum 300 m3 and pressure of
approximately 10 bar.

The CTM CCGT will have its own fire water fighting system with pump house, and
fire water will be provided from the raw water tanks.

The new pumps will consist of:

One 100% electric jockey pump
One 100% electric driven main pump
One 100% diesel engine driven main pump

The water demand and required pressure for the worst case scenario will be ensured by the electrically
driven main pump, a second duty diesel engine driven pump shall be on stand-by in the case of main
supply failure. The engine driven pump will be of the same capacity as the electric driven main pump.

Table 6.4-8 List of protected areas and fire fighting and detection systems types
Item Building or Area Fire Fighting System
１ Gas turbine CO2 extinguishing system
2 Steam turbine lube oil package, Spray water dry type
lube oil piping
3 Steam turbine bearings Spray water dry type
4 Steam turbine building indoors Wet stand pipe house system
5 Generator unit, auxiliary and start Spray water dry type

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Item Building or Area Fire Fighting System

up transformer
6 Oil tanks Form system, dike protection
Cable basement: Sprinkler system
7 Control room
Control room: Argonite or similar
Sprinkler system if required and
8 Electrical/ switchgear
portable fire extinguishers
9 Yard Hydrants
Protective signaling for fire and gas
10 Common areas detection systems with main panel in
the control room
(Source: JICA Study Team)

(2) Fire fighting system description

The fire fighting system of the CTM CCGT will be provided for the plant as described as follows. In
general, the fire fighting system will follow the applicable stipulations of NFPA codes. Extinguishers
will be sized, rated and spaced in accordance with NFPA 10. Local buildings fire alarms, automatic
fire detectors and the fire signaling panel will be in accordance with NFPA 72.

A dedicated two hour fire water supply will be assured to cover the system design flow rate for the
facility in accordance with NFPA. A main firewater pipeline will be provided to serve strategically
placed yard hydrants and supply water to the sprinkler and spray system. The firewater distribution
system will incorporate sectionalizing valves so that a failure in any part of the system can be isolated
while allowing the remainder of the system to function properly. Fuel oil tanks will be furnished with
foam fire fighting systems.

6.5 General Specification of Electrical and Control System

6.5.1 Electrical Facility

Outline of electrical system
GT generator-A will be connected via a single generator step-up transformer to the 66 kV substation.
And GT generator-B and the steam turbine generator will be connected via a three-winding
transformer to the 66 kV substation. Because of above methods can decrease the requirement only one
transformer, these methods are more economical than using both a generator and a transformer.
In addition, for connection to the system, only two sets of switchgears are used at the 66 kV substation.
As the existing 66 kV GIS substation to be used has a two-section, single-bus configuration, all the
transmission lines connected to the bus must be shut down in order to add a breaker. Currently,
however, two switchgear bays are empty as two transformers have been removed to be connected to
the 35 kV substation. Therefore, there are plans to connect the two generator step-up transformers to
these switchgear bays. Thus no shut down of the 66 kV transmission line will occur.
For connection of the ordinary generators to the system, generator main circuit breakers ( “GMCBs”)
will be used. The GIS in the 66 kV substation will be used for re-parallelization to the system after
auxiliary load operation. An outline of the electrical system is shown in Figure 6.5-1.

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(Source: JICA Study Team)

Figure 6.5-1 Outline of electrical system

(1) GT and steam turbine generators

a. Generator specifications
The generator standards shall be as listed below:
Table 6.5-1 Generator specifications
GT generator (2 units) Steam Turbine generator (1 unit)
Generator type Three-phase AC synchronous Three-phase AC synchronous generator
generator
No. of poles 2 2
Phases 3 3
Capacity 24 MW to 48 MW 2 0 MW to 30 MW
Frequency 50 Hz 50 Hz
Speed of 3,000rpm 3,000rpm
rotation
Terminal 11 kV 11 kV
voltage
Power factor 0.85 (lagging) operation lag 0.85 to 0.85 (lagging) operation lag 0.85 to lead
lead 0.95 0.95
Short-circuit Not less than 0.45 Not less than 0.45
ratio
Insulation class Stator: Class F; Rotor: Class F Stator: Class F; Rotor: Class F
(Source: JICA Study Team)

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The rated output values of the generators shall correspond to the maximum output values of the GT
and the steam turbine. The above generation capacities show approximate ranges with regard to the
CCGT that is expected to be used. In addition, the rated voltage values are those generally used for
20-40 MW-class generators. Finally, the design voltage of the generator manufacturer will be applied.
The rated power factor shall be a delay of 0.85. The normal operation power factor shall be a range
from a lag of 0.85 to a lead of 0.95.
From the viewpoint of system stability, a larger short-circuit ratio is advantageous. However, the
short-circuit ratios have been reduced due to downsizing of machines and speeding up of the
automatic voltage regulators (“AVRs”). For the Maputo CCGT, the specification shall be for a
minimum value of 0.45. This value is also acceptable from the viewpoint of system stability
calculation. (Recommended value by IEC 60034-3: When rated output does not exceed 80 MVA in
the case of air cooling: 0.45 or higher)

b. Generator cooling facility

The cooling for the GT and steam turbine generators shall be an air cooling type. Whether to use an
open air cooling method or a water-cooler shall depend on the generator manufacturer’s
recommendation.

c. Excitation system
Each generator is supplied with the field current by a static thyristor exciting arrangement or a rotary
rectifier exciting arrangement (brushless exciter). The excitation system includes necessary
components such as an excitation transformer, a field circuit breaker, and an initial excitation device.
For the stationary thyristor exciting arrangement, the excitation transformer shall be split from the
generator main circuit and thus supply from any other power source shall not be allowed.

d. AVRs
AVRs shall be of an immediate response excitation type. For the AVR, a dual system of a
microprocessor type shall be used. AVR devices should be installed in air-conditioned rooms. The
AVR functions shall include:
 Automatic voltage regulator (90R)
 Field voltage regulator (70R)
 Over excitation limiter (“OEL”)
 Under excitation limiter (“UEL”)
 Power system stabilizer (“PSS”)
 Automatic reactive power regulator (“AQR”)
 Automatic power factor regulator (“APFR”)
 Other necessary functions
e. GT start up method
The GT start up method shall use a motor-driven torque converter, a hydraulic pump or a thyristor,
depending on the contractor’s recommendation.

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(2) Generator main circuit

a. Current transformer (“CT”)
A CT shall be installed on the bushing of the generator main terminal. The CT shall be installed to be
used for metering including generator ratio differential relay, transformer ratio differential relay, other
protective relays and the watt-hour meter. The CT for metering shall be of accuracy class of 0.2. The
current rating on the secondary side shall be one A.

b. Voltage transformer (“VT”) and surge arrestor (“SA”)

Instrument VT, SA and generator grounding device will be installed between the generator and the
generator main circuit breaker (“GMCB”). They will be installed in an independent cubicle or on the
GMCB board. The VT used for metering, including the watt-hour meter, shall be of accuracy class of
0.2. The surge condenser capacity shall be as recommended by the manufacturer.

c. Neutral grounding device

The neutral point of the generator shall be grounded via a resistor or the secondary-side single-phase
transformer with a resistor. The transformer shall be a dry-type transformer. The resistor shall be a
metal grid, non-inductive resistor. A single-core cross-linked polyethelene (“XLPE”) cable shall be
used between the generator main terminal and the neutral grounding device.

d. Generator main circuit breaker

A GMCB will be installed between the generator and the generator step-up transformer for generator
synchronizing on and off. The continuous rated current of the circuit breaker shall be selected so that it
corresponds to the maximum load of the generator. Short-circuit current capacity of the GMCB shall
be selected on the condition that a short-circuit current of 25 kA at maximum flows into the bus line of
the 66 kV substation. For synchronous detection, a VT shall be installed on the step-up transformer
side of the GMCB.
In addition, a grounding device shall be installed on each side of the GMCB for safety work..
e. Main circuit connection
XLPE cables that correspond to the individual voltage classes shall be used between the generator and
the GMCB, between the GMCB and the generator step-up transformer, and between the generator
step-up transformer and the 66 kV substation. The cables shall be single-core, wire-armored cables.

(3) Major transformers

The connection conditions of the GT transformers, the steam turbine transformers and the auxiliary
transformers are shown in Fig. 6.5-1 “Key single line diagram” A one step-up transformer is
connected to GT generator-A. GT generator-B and the steam turbine generator are connected to one
three-winding transformer for power transmission to the 66 kV substation. The two auxiliary
transformers are respectively split from the circuits of GT generator-A and GT generator-B.

a. Generator step-up transformer

The generator step-up transformer boosts the generator voltage (11 kV class) to the transmission
voltage (66 kV). The transformer shall be an oil-insulation, outdoor-type, three-phase transformer with
an off-load tap changer. The transformer winding type of GT generator-A shall be a two-winding type,

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Y-Δ (YNd11). The transformer winding type of GT generator-B/ steam turbine generator shall be a
three winding type, Y-Δ-Δ (YNd11d11). As the transformer cooling method, Oil Natural Air Natural/
Oil Natural Air Forced (“ONAN”/ “ONAF”) shall be used. The neutral point on the high voltage side
shall be direct grounding. The rated capacity on the name plate shall be based on calculation and
discussion.

b. Auxiliary transformer
The unit auxiliary transformer (“UAT”) reduces the GT generator voltage (11 kV) to the auxiliary
power voltage (6.6 kV). The UAT shall be an oil-insulation, outdoor-type, three-phase transformer
with an on-load tap changer, and the cooling method shall be ONAN. The transformer winding type
shall be Δ-Y (Dyn1). The neutral point on the 6.6 kV side shall be resistant grounding (5 ohms). Two
UATs with the same capacity shall be installed. Ordinarily, the two transformers shall both be in
service but they shall have the capacity to cover the entire load even if one of them breaks down.
The JICA Study Team has temporarily assumed the transformer capacity to be 3 MVA but the final
capacity shall be based on the auxiliary power design by the contractor. The plan is based on a 6.6 kV
load, and the gas compressor and GT starting equipment are assumed to have a 6.6 kV load. If a bidder
provides a design that is not a 6.6 kV load, the secondary transformer voltage will be set to 400V. In
this case, a transformer neutral point shall be directly grounding.
Table 6.5-2 Transformer specifications
GT Generator-B/ Auxiliary
GT Generator-A
Item Steam Turbine Transformer
Transformer
Transformer (2 sets)
Primary 66 kV 66 kV 11.0kV
Rated 11 kV 11 kV 6.6kV
Secondary-1
voltage
Secondary-2 --------- 11kV ---------
Rated Primary 411A 717A 158A
current Secondary-1 2467A 2467A 263A
Secondary-2 --------- 1638A ---------
Primary 47MVA 82MVA 3 MVA
Rated
Secondary-1 47MVA 47MVA 3 MVA
capacity
Secondary-2 --------- 35MVA ---------
Winding YNd1 YNd1d1 Dyn11

ONAF ONAF ONAN

Cooling method

(Source: JICA Study Team)

The above list shows an example of using a GT with an output of 40 MW and an steam turbine with
an output of 30 MW. Note that the maximum output of the GT is based on an atmospheric temperature
of 10C and therefore differs from the actual rating described on the plate of the generator step-up
transformer.

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(Source: JICA Study Team)

Figure 6.5-2 Key Single Line Diagram - 1

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(Source: JICA Study Team)

Figure 6.5-3 Key Single Line Diagram – 2

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(4) Auxiliary power supply

The auxiliary power supply system consists of two UATs. Including common facilities (water
treatment, sewage treatment and other facilities), the facilities used in the Maputo CCGT will be
supplied with power from the UATs.
In addition, the Maputo CCGT will be equipped with a 3-phase diesel generator for emergency
power supply so as to protect and maintain the power supply in the case where there is a total
power station blackout.

a. 6.6 kV medium voltage switchboard (if 6.6 kV load is required)

The 6.6 kV medium voltage switchboard will supply the auxiliary equipment driving power that
is required for power generation facility operation and common operation power. The 6.6 kV
auxiliary bus lines consist of lines A and B. The bus lines are of a 3-phase, 3-wire type. Each
6.6 kV auxiliary bus will be supplied with power from the auxiliary transformer split from the
main circuit of each GT generator. The 6.6 kV medium voltage switchboard will supply power
to the 6.6 kV facilities and the 400 V auxiliary bus.
The 6.6 kV bus lines, A and B, will be connected via a bus connection breaker. The bus
connection breaker will normally be open. The 6.6 kV medium voltage switchboard shall be
equipped with an automatic high-speed bus switcher. At the time of start up and shut down, and
even during operation, the whole Maputo CCGT load can be supplied with power by switching
the bus connection breaker on in the case where one of the UATs is suspended.
The power panel shall be of a metal clad type and the breaker shall be either a vacuum circuit
breaker (“VCB”) or a gas circuit breaker (SF6CB). (Refer to “Key Single Line Diagram –1.)

b. 400 V switchboard
The 400 V switchboard shall supply power to the middle-capacity electric motors and the motor
control center (“MCC”). The power will be supplied from the 6.6 kV bus via a 6.6/ 0.4 kV
dry-type transformer. The neutral point of the transformer shall be directly grounded. The bus
lines shall be of a 3-phase, 4-wire type. Buses are formed with the line bus (“L1”, “L2”, and
“L3”) and neutral bus (“N”).
In composition without a 6.6 kV medium voltage switch board, the electricity will be supplied
from a 11/0.4kV unit axially transformer. Please refer to “Key Single Line Diagram – 2.”
c. MCC
The MCC shall supply power to the small electric motors and 400 V or 230 V power to the
plant. The bus lines are of a 3-phase, 4-wire type. Buses are formed with the line bus (i.e., L1,
L2, and L3) and neutral bus (N). The 230 V single-phase loads are supplied from power
between the neutral line and phase lines. The switchgear shall be of a drawer type.

d. Emergency AC power facility

One set of diesel generator facilities shall be installed. Emergency power shall be sent from the
diesel generator to the 400 V emergency bus line in the case of blackout. The objective of the

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diesel generator is the safe shut down of the plant in the case of a blackout. It shall not be used
for black start of the plant.
The generator capacity shall be sufficiently tolerant for the safe shut down of the plant. The
major loads will include the AC bearing oil pumps, AC control oil pumps, gas turbine
ventilation fans, battery chargers, uninterrupted power supply (“UPS”) units, and emergency
AC lighting, etc.

e. Uninterrupted power supply (UPS)

UPS units shall be installed to supply the plant control power or AC 230 V power to important
loads for which power loss is unacceptable. The UPS units shall be designed as 230 volts
alternating current (“VAC”), single-phase, 2-wire and 50-Hz.
The UPS unit shall consist of an AC-to-DC converter, DC-to-AC inverter, static switch with a
voltage regulator for switching to the AC bypass power, and a maintenance bypass transformer.
The UPS units shall be supplied with DC power from the 220 volts direct current (“VDC”)
power supply facility for CCGT.

f. 220 VDC power supply facility

The 220 VDC power supply facility shall consist of two 100%-capacity battery chargers and a
group of 100%-capacity batteries. The batteries shall be able to assure safe shut down of the
power generation facility in the case there is a blackout of the Maputo CCGT.

(5) Protection and measurement of generators and transformers

For protection of the generators and the generator step-up transformers, there shall be a dual
system of a microprocessor type. The DC and AC control power supplies will also be duplex.
In addition, the breaker tripping signal shall be duplex via two lockout relay systems (86). The
table below shows the basic configuration of relays to be used for protection of the generators,
generator step-up transformers and other main circuits.

a. Generator protection
Table 6.5-3 Generator protection relays
Name Element
Generator Differential protection 87G
Generator Negative Sequence protection 46G
Generator Loss of Excitation protection 40
Generator Reverse Power protection 32R
Rotor Earth Fault Protection 64R
Out-of-Step Protection 78
Generator Stator Earth Fault protection 59NG
Generator Over Current protection 51G
Generator Stator Overload protection 49G
Generator Backup Impedance protection 21G

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Name Element
Generator Over Voltage protection 59G
Generator Under and Over Frequency protection 81
Generator Under Voltage protection 27G
Over Excitation protection U/f U/F24G
Protection of other exciters
(Source: JICA Study Team)

b. Generator step-up transformer protection

Table 6.5-4 Generator step-up transformer protection relays
Name (Electrical Protection) Element
Differential protection 87T
Phase Over Current protection 51
Differential Earth Fault Current protection 87N
Thermal Overload protection 49
Negative Sequence protection 46
Name (Mechanical Protection) Element
Buchholz relay 96P1
Sudden pressure response devices 96P2
Transformer oil temperature relay 26 Oil
HV winding temperature relay 26WH
LV winding temperature relay (GT, GT/ ST) 26WL
LV winding temperature relay (GT/ ST) 26WL
(Source: JICA Study Team)

c. Auxiliary transformers protection

Table 6.5-5 Auxiliary transformer protection relays
Name (Electrical Protection) Element
Differential protection 87T
Phase Over Current protection 51
Earth Fault Over Current Protection 51N
Thermal Overload protection 49
Negative Sequence protection 46
Name (Mechanical Protection） Element
Buchholz relay 96P1
Sudden pressure response devices 96P2
Transformer oil temperature relay 26Oil
HV winding temperature relay 26WH
HV winding temperature relay 26WL
Protection of the tap changer 63OLTC
(Source: JICA Study Team)

d. Electrical control measurement

Generator parallelization on and off signals shall be transmitted from the DCS via the generator
controller or the protection relay to the GMCB or the 66 kV substation by use of hard wires.

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Also by use of hard wires, the current and voltage signals shall be connected from the CT and
the VT to the generator control panel or the protection relay.
Devices with accuracies of 0.2 or higher shall be used for measuring instrumentation with
regard to the watt-hour meters and the performance tests. Gauges for on-site operation
monitoring shall be of class 1.5 or higher.

(6) Substation and power lines

As described in the inception report, the JICA Study Team plans to use the existing power
transmission facility without enhancement of the power lines. Based on this assumption,
transmission methods of power generated by the CCGT via the CTM Maputo 66 kV substation
shall be planned. Three circuits of 66 kV transmission line and one 30 MVA transformer for 33
kV substation connection shall be connected to 1A Bus of CTM Maputo 66 kV substation.
Moreover, five circuits of 66 kV transmission line and one 30 MVA transformer for 33 kV
substation connection shall be connected to 1B Bus. There were once four transformers but
two have been removed and now there are bus lines 1A and 2A, respectively, with one empty
switchgear bay. This is suitable as the plan to connect two generator step-up transformers for
CCGT.

The connection location of the step up transformer and the current composition of 66 kV GIS
are shown in Figure 6.5-4.

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(Source: JICA Study Team)

Figure 6.5-4 GIS layout and connection point

6.5.2 Control and Monitor System

(1) System outline

All the designs of the control and monitoring system shall be provided to maintain the
maximum safety of the CTM CCGT employees and equipment and, on the other hand, the
system shall have the highest usability as far as can be expected so that it can be operated in a
safe and efficient manner in all conditions. The control and monitoring system that will realize
all-automatic operation of the generator facility will be configured as a DCS that takes
technology and costs into consideration. The DCS facility will make it possible to control and
monitor the whole generator facility, including control and monitoring of common facilities.

In addition, the existing CTM CCGTs No. 2 and No. 3 shall be controllable from the
newly-built central control room as well as from the CTM CCGT. The system outline is shown
in Figure 6.5-5 “Outline of Plant Control.”

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The basic design of the DCS facility is as follows:

 Operation and power circuits shall be duplicated.
 Input/ output circuits will be of a single type. However, important circuits will be doubled.
 The power supply will be duplexed by AC and DC (butted method).
 The trunk network will be doubled.
 In principle, operation should be carried out by use of a computer mouse.

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(Source: JICA Study Team)

Figure 6.5-5 Outline of Plant Control

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(2) Configuration of power plant control and monitoring system

The control and monitoring equipment for the power plant will consist of a DCS facility, an
information management system, a maintenance management system, a network system and related
equipment.

The DCS facility will consist of an operator console, a turbine control system, a data logging system, a
sequence control system, a process input/ output (“I/O”) system and related peripheral machinery,
which will be connected via a network.
The standard performance of the instrumentation and transducer are as follows:
 On-site monitoring instrumentation: Accuracy class 2.0 or higher
 Transducer: Accuracy class 0.25 or higher
 Transducer related to performance: Accuracy class 0.2 or higher

(3) DCS function of the power plant

In the design of the CTM CCGT control and monitoring system, there will be the integration of a
combination of a GT and a GT generator, a combination of an steam turbine and a steam turbine
generator, a combination of an HRSG and a BOP (auxiliary machine), and exclusive control
equipment with an air compression facility, etc., using a data logging system and a DCS of the latest
technology.

The operator console installed in the CCR shall consist of a keyboard, a computer mouse and a dual
display (two liquid crystal displays (“LCDs”)). The GT control system, the steam turbine control
system, and the HRSG and local control system shall be connected to the DCS via redundant
communications links and by use of hard wiring signals. The signals from such systems as the air
compressor control system and the auxiliary steam supply control system shall be sent to the DCS I/O
cabinet either directly or via remote I/O units. The LCD graphics will provide the operators
information on the control and monitoring of instrument and process conditions, records and alarms.

The detection system for protection control of the GT, steam turbine and the HRSG shall be
redundancy/ triple configuration (2 out of 3) to improve the reliability of the generator facility. The
control system shall be designed so that the generator facility can be operated and controlled
automatically and the operators can be informed of the power plant status, start up/shut down status,
troubleshooting status and normal operation status.

The configuration of the control logic and graphic display of the control system shall be designed so
that maintenance staff can carry out on-site corrections and modifications easily and without making
mistakes.
DCS shall have the following functions:
a. Turbine control and monitoring functions
 GT control and monitoring and GT protection circuit

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 HRSG control and monitoring and HRSG protection circuit

 Steam turbine control and monitoring and steam turbine protection circuit
 Condenser control
 Control of control system
 Control of bearing oil system
 Control of synchronization
 Generator protection, excitation control, and voltage control
 Auxiliary and BOP control and monitoring
b. Information collection/ control functions
 Scanning and alerting
 Process calculations (including performance calculations)
 Data log functions and data display
 Functions to control and monitor common facilities
 Fuel gas facility
 Water treatment system
 Wastewater treatment system, etc.

These systems will have independent monitoring and control. In the event of any defect in the
equipment, the impact on the power station will be large. For this reason, the calculation system and
power supply system, etc., are multiplexed in order to contribute to the reliable operation of the
system.
c. Maintenance functions
Maintenance tools (an Engineering Work Station) for the maintenance of DCS shall be installed and
these tools shall have the following functions:
 Control circuit setting/ changing functions
 System diagram displaying/ changing functions
When specified under the treaty of LTSA, remote monitoring from the office of the maker of the gas
turbine equipment will be possible.

d. Functions for connection with SCADA

In order to monitor the intelligence on substations connected to the generator of CCGT, there shall be
a communication system between SCADA and the power plant. In order for the communication
system to match that of SCADA’s, DCS shall make preparations for such system. DCS will send data
and signals that are requested by the dispatch center section.
.

(4) Communications system

A communication system will be established for the management, supervision and correspondence of
the power plant.
a. Telephone facility
Cordless telephones shall be prepared for plant yard connection. Private branch exchange (“PBX”)
shall be installed and used for connection to the public telephone network and internal calls. The
facility will include a main distributing frame (“MDF”), PBX, extension terminal box, wireless
transmitters, and terminal handsets.

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b. Walkie-talkie system
A walkie-talkie system of a frequency and output recognized by the Mozambique government shall be
used. Using multiple frequency bands and extension handsets, the master station of the wireless
installation, which will be installed in the CCR, will allow broadcast calls and calls between extension
handsets set to the same band

c. Clock device
Clock equipment with a global positioning system (“GPS”) shall be installed. The DCS and major
control equipment shall be synchronized with the clock equipment. Synchronization with the SCADA
system shall also be taken into consideration.

d. LAN system
A local area network (“LAN”) system will be established plus the internet/intranet system to be used
in the CCR, general offices and conference room, etc.

e. CCTV system
Closed-circuit television (“CCTV”) equipment will be installed for remote monitoring of the device
operation conditions and for yard security monitoring. The equipment shall use color cameras and offer the
following functions: nighttime monitoring, zoom functions, tilt functions, and automatic and manual focus
adjustment functions. The monitoring screens shall be installed in the CCR and security office.

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6.6 Civil and Architectural Works

6.6.1 Major Components of Civil and Architectural Works

Major components of civil and architectural works include the following:

 Foundation works (including removal of the existing oil tanks and relocating the power cable of the
existing No. 3 Gas Turbine)
 Steam turbine building
 Control building
 Other buildings (i.e., warehouse, workshop, etc.)
 Storm drainage system
 Road work

6.6.2 Earthquakes
Figure 6.6-1 shows the distribution of earthquake epicenters in the Eastern and Southern African regions
for the period 627–1994 for earthquakes with a magnitude stronger than 4.0. This figure reveals that major
earthquakes have not occurred within a radius of around 200 km and only earthquakes with a mid-class
magnitude (<7.0) have occurred within the radius of 300 km.

Furthermore, Figure 6.6-2 shows the distribution of the expected peak horizontal ground acceleration due
to earthquakes, which have a 10% probability of occurring within the next 50 years in Mozambique. From
this figure, it is obvious that Maputo city is situated in an area with a low risk of earthquakes and a peak
horizontal ground acceleration of less than 0.2 g (200 gal).

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Maputo

（Source: Seismic hazard assessment in Eastern and Southern Africa, 1999）

Figure 6.6-1 Seismicity of Eastern and Southern African Regions

Maputo

（Source: USGS）

Figure 6.6-2 Distribution of the expected peak horizontal ground acceleration (possibility of
10% within 50 years)

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6.6.3 Design Conditions

(1) Ground Level

The average ground level of the site is approximately 3.3m above mean sea level (“M.S.L.”) of Port
Maputo. Figure 6.7-3 shows the relationship between tidal levels and the ground level of the site.

G.L≒NM+3.3m (=C.D+5.3m)

1.4m
Maximum tidal level
PMmax=C.D +3.9m
Mean high-water springs
PMav=C.D+3.5m

Mean sea level (MSL)

NM=C.D+2.0m (M.S.L)

Mean low-water springs

BMav=C.D+0.5m
Hydrographic “zero”
Chart datum (C.D)

（Source: Prepared by JICA Study Team based on information obtained from INAHINA）

Figure 6.6-3 Relationship between tidal levels and ground level of the site

The maximum tidal level (PMmax) in the above is defined as “the maximum astronomical tide level that can
be observed in normal weather conditions” and it does not mean the highest recorded tidal level. According
to INAHINA, PMmax is usually observed in April.
Since the ground level is the elevation above MSL, the ground level of CTM has an allowance height of 1.4
meters above the maximum tidal level2. In general, a local decrease in surface air pressure over the ocean
produces an increase in the sea surface of 1 cm per hPa. If a perfect coincidence of PMmax and extreme low
pressure (i.e., brunt of a tropical storm) occurs, the expected rise in the sea surface is approximately 1.0
meters, which is still 0.4 meters lower than the ground level of CTM. Accordingly, it is not likely that CTM
will be affected by storm surges.3 Thus, it is not necessary to raise the ground level of the CTM site against
storm surges.

2
According to INAHINA, for planning and design of the facilities in port of Maputo, the planned ground plane
is set at PMmax+0.5 m.
3
According to INAHINA, the recorded maximum tidal level at Port Maputo is not more than C.D+5.0 m.
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(2) Design Wind

Mozambique does not have its own building design code and usually follows the Portuguese design code or
other international codes and standards for design of important structures and buildings.
The design wind speed for the Project shall be determined based on the past maximum wind speed records
during tropical storms.
(3) Design Seismic Coefficient
As previously mentioned, Mozambique does not have its own building design code. According to the
Uniform Building Code (1997), the seismic zone of Maputo city is categorized as “2A.” Assuming the soil
type of the site as “CD (stiff soil profile),” the horizontal design seismic coefficient is estimated at 0.071,
which corresponds to a horizontal acceleration of 71 gals. This concurs with the seismic hazard of 10%
within 50 years for the site (less than 200 gal) as previously mentioned in Section 6.1-2.
(4) Design Rainfall Intensity
The National Directorate of Water (DNA) in the Ministry of Public Works and Housing stipulates the
design standards of the storm water drainage system and sewerage. The following formula is provided to
calculate the design rainfall intensity of Maputo city. This formula can be applied to the design of the storm
water drainage system for the Project.

I(mm/h) = a x t (min)b
Where,
T: return period
I: rainfall intensity (mm/h)
a, b: constants (see the table below)
t: duration of rainfall (mm)

Table 6.6-1 Rainfall intensity for various return periods

T (year) 2 5 10 20 25 50
a 534.0468 694.504 797.3841 896.5751 930.8815 1026.694
b -0.5075 -0.59383 -0.5869 -0.58197 -0.58119 -0.57749
(Source: Regulation of public systems for water supply and wastewater drainage (Decree 30/2003, 1. July;
DNA, 2003))

In the above formula, assuming a return period of 50 years and a rainfall duration of 1,440 minutes (i.e., 24
hours), the rainfall intensity is estimated at 13.6 mm for a period of 24 hours, which corresponds to the total
daily rainfall of 326 mm. It was found that this figure coincides with the recorded maximum daily rainfall
observed on February 6, 2000. Accordingly, the return period of 50 years shall be adopted for design of the
storm water drainage system of the Project.

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6.6.4 Design of Foundations

(1) Selection of Foundation Type
Since foundation settlement should be avoided for the major equipment and structures, a pile foundation is
basically adopted. In selection of the pile used in this Project, compatibility with soil condition on the site,
past experience of construction in the region, market availability, etc. shall be taken into consideration.
From the viewpoint of market availability, cast-in-place piles could be the most appropriate for this Project.
Spread foundations could be used for pipe racks; however, the larger footing of spread foundations may
cause interference with the other structures. Thus, the pile foundation is also recommended for pipe racks.
For other miscellaneous structures and cable trenches, a spread foundation will be adopted.
Since the existing oil tanks and oil containment dykes interfere with the foundation of gas turbines, stacks,
HRSGs, and pipe racks, they must be totally demolished and removed from the site before the foundation
work starts. It is appropriate that the existing piles, which support the oil tanks, be buried after removal of
oil tanks. Accordingly, the location of existing piles shall be surveyed before being buried and plotted on
the drawings in order to avoid interference with piles for foundations of the equipment and structures.

(Source: EDM)

Figure 6.6-4 A photo showing installation of the existing oil tanks (in 1970s)

(2) Preliminary Study of Foundation Design

(a) Design conditions

Major design conditions are summarized in the following table.

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Table 6.6-2 Design conditions

Item Description
Design process and 1) The sectional design of the foundation is based on the allowable stress
evaluation method.
2) A vibration analysis is conducted to ensure that the natural frequency of
the foundation meets the requirements for vibrating machines (e.g., GTG,
STG, etc.)
Soil conditions Soil constants are estimated by using empirical formulas for cohesive soil
based on N-values obtained from the soil investigation.
Loading conditions The following loads are considered for design of foundations.
1) Machine load
2) Dead load (i.e., weight of concrete with a unit weight of 24 kN/m3)
3) Seismic load
Allowable bearing The allowable bearing capacity of cast-in-place pile is estimated by using the
capacity of pile following empirical formula.
- Long-term allowable bearing capacity: Ra = 1/3･Rp + 1/3･Rf
- Short-tem allowable bearing capacity: Ra = 2/3･Rp + 2/3･Rf
- Ultimate end bearing capacity: Rp = 150･N･Ap
- Ultimate skin friction resistance: Rf = 10/3･Ns･Ls･φ + 1/2 qu･Lc･φ
Where,
Ap: Effective sectional area at the tip of pile (m2)
N: Average N-value at the tip of pile
Ns: Average N-value of sandy soil
Ls: Contact length of pile with sandy soil (m)
Φ: Peripheral length of pile (m)
qu: Unconfined compression strength of cohesive soil (kN/m2), which is
estimated by using the empirical formula, qu=12.5 N (<200 kN/m2)4.
Lc: Contact length of pile with cohesive soil (m)

(Source: JICA Study Team)

(b) Results of study

For design of the vibrating machines (gas turbines and a steam turbine), the cross-sectional area of the
foundation is determined based on the required dead weight of foundation against sympathetic vibration
with equipment, as determined in the vibration analysis. For instance, the thickness of the mat foundation
of a gas turbine is estimated at 2.0 meters, which is much bigger than the required foundation depth based
on the static stress analysis and results in minimum reinforcement.

Figure 6.7-5 shows an outline drawing for the foundation of a gas turbine. The structural calculation sheet
for the gas turbine foundation is contained in the Appendix of this report.

4
Guideline for Structural Design of Foundations, Yokohama City.
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(Source: JICA Study Team)

Figure 6.6-5 Outline drawing for foundation of gas turbine

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6.6.5 Architectural Works

The specifications required for the major buildings for the Project are summarized in Table 6.1-2.

Table 6.6-3 Specifications of major buildings for the Project (draft)

Name of building Specification

Steam turbine building  The building is a steel frame structure equipped with overhead
travelling crane(s)
 Side walls are constructed with corrugated plates and steel plates and
roof structures are constructed with steel truss
 Windows and louvers provided for ventilation purposes
 Structures to be designed for a lifetime of 20 to 30 years
Control building  The building is a reinforced concrete structure
 The walls are constructed with bricks with holes, cement blocks or
concrete
 An air conditioning system shall be provided in the majority of
rooms
Workshop  The building is basically of one span and one story
 Steel frame structure equipped with a crane
Warehouse  Specification are the same as the workshop
(Source: JICA Study Team)

6.6.6 Storm Water Drainage System

As explained in Section 5.1.1 of this report, since the embankment of the highway located to the north acts
as a topographic divide, rain that falls on the north side of the highway does not flow in the direction of
CTM. In addition, since drainage channels with sufficient capacity have been provided on both sides of the
railway embankment, there is little chance that storm water will flow into the CTM site from the outside
(see the left-hand photos in Figure 6.6-6 and Figure 6.6-7).
On the other hand, there is no appropriate drainage system in CTM. This is considered to be the major
cause of the flood damage that occurred in the No.1 GT and No.2 GT buildings when torrential rain hit
Maputo city on February 6, 2000.

Since the No.1 GT and No.2 GT buildings are located in a relatively lower area in CTM where rainwater
tends to gather, storm drains are provided in this area. However, periodical maintenance of storm drains is
seemingly not done and the opening of the storm drain nearest the No.1 GT building was completely
clogged with soil (see the right-hand photo in Figure 6.6-6). Furthermore, the drainage pipe (φ300 mm) is
not exposed at the end point but is apparently buried in the ground. Thus, it is obvious that storm water in
CTM is not properly discharged when heavy rain occurs.

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(Source: JICA Study Team)

Figure 6.6-6 A drainage channel parallel to railway (70 cm wide) and a storm drain in CTM

The floor level of GT buildings is set at almost the same level as the ground level of the surrounding area;
thus, it may contribute to flood damage in GT buildings. In fact, no flood damage occurred in the canteen,
which is situated close to GT
buildings but whose floor level is set at approximately 20 cm higher than the ground level of the
surrounding area.
In conclusion, a new storm water drainage system with sufficient capacity in accordance with the design
rainfall intensity (50-year return period) shall be established in CTM. In planning and design of the storm
water drainage system for CTM, the following basic design policy shall be considered:

 The catchment area shall be divided into two by the existing road that runs in the east-west direction.
 Open ditches shall be used as practicably as possible in order to facilitate easier maintenance of the
drainage system.
 Inverted siphons shall be used to convey storm water across existing cable trenches. The diameter of
the inverted siphon pipes shall be at least 800 mm for easy maintenance.
 An oil separator shall be provided at the end point of each drainage system.

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Legend The drainage pipe is buried in the ground.

Thus stormwater in CTM Maputo is not
Drainage ditch/pipe properly discharged.

(Source: JICA Study Team)

Figure 6.6-7 Existing drainage system in and around the CTM

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 Chapter 7

Natural Gas Supply Plan

 Preparatory Study on Gas-Fired Power Plant Development in Southern Mozambique Final Report

Chapter 7 Natural Gas Supply Plan

7.1 Overview of Natural Gas in Mozambique

At present, Mozambique has two gas fields: one in the Rovuma Basin of Cabo Delgado province in
the north and the other in the Mozambique Basin of Inhambane province in the south. Their locations
are illustrated in Figure 7.1-1

In the Mozambique Basin, gas was first found in the Pande area in 1961, then in the Buzi area in 1962,
followed by the Temane area in 1967. After that, natural gas development has been sluggish since the
1970s due to the absence of demand and political instability in Mozambique. In 2003, gas was found
in the Inhassoro area, and natural gas development was promoted by the enactment of the Petroleum
Law (3/81) and establishment of the Mozambican National Hydrocarbon Company (“ENH”) since the
1990s. Since the mid-1990s, Production Sharing Agreements (“PSA”) and Engineering, Procurement
and Construction (contracts) (“EPC”) have been signed with international oil developers (Arco in
1997, BP in 1998, and Sasol, Petronas, Hydro and DNO in 2000 and onward). Thus, natural gas
development has been promoted, including the construction of gas pipelines going to South Africa by
Sasol.

In the Rovuma Basin, tenders for development licensing have been invited since 2005. As a result,
development and licensing agreements were signed with global developers such as Anadarko (U.S.A.),
ENI (Italy), Petronas (Malaysia) and Artumas (Canada). Since then, natural gas development has been
promoted.

In the Pande and Temane areas in the Mozambique Basin, natural gas sources have been developed
and natural gas has been produced under a Petroleum Production Agreement (“PPA”) between Sasol
Petroleum Temane and ENH.

In 2004, the first commercial production was initiated in the Temane area. In 2009, production started
in the Pande area.

(Source: ENH)

Figure 7.1-1 Gas Fields in Mozambique

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The following table lists the development and production areas with developers and producers in the
Rovuma Basin and Mozambique Basin.

Table 7.1-1 Development and Production Areas in the Rovuma Basin

and Mozambique Basin
Rovuma Basin
Block Partners
Onshore Rovuma Anadarko (35.7%), Wentworth (15.3%), Maurel & Prom (24%), ENH
(15%), Cove Energy (10%)
Area 1 Anadarko (36.5%), Mitsui (20%) ENH (15%), Bharat Petroleum
Corporation (10%), Videocon Energy Resources (10%), Cove Energy
(8.5%)
Area 4 Eni (70%), ENH (10%), Galp (10%), Kogas (10%)
Area 2 & 5 Statoil (90%), ENH (10%)
Area 3 & 6 Petronas (90%), ENH (10%)
Mozambique Basin
Block Partners
Pande - Temane Sasol (70%), ENH (25%), IFC (5%)
16 & 19 Sasol (50%), Petronas (35%), ENH (15%)
Sofala Sasol (85%), ENH (15%)
M10 Sasol (42.5%), Petronas (42.5%), ENH (15%)
Buzi Buzi Hydrocarbons (75%), ENH (25%)
Area A Sasol (90%), ENH (10%)
(Source: ENH)

According to available data, reserves of natural gas in Mozambique are 4.8 to 8.8 trillion cubic feet
(“TCF”) in the Mozambique Basin and 52.5 to 110 TCF in the Rovuma Basin. There are several
sources of data showing recoverable reserves, which lie in the range of 5.504 to about 10 TCF, 7% of
which have already been found. The area-wise recoverable reserves in the Mozambique Basin are
2.321 to 2.7 TCF in the Pande area, 0.618 to 1.0 TCF in the Temane area and 14 billion cubic feet
(“BCF”) in the Buzi area.

Current production volume in Mozambique is approximately 130 million gigajoules (“MGJ”) per
annum from the Pande and Temane areas of the Mozambique Basin. More than 95% of the gas
produced is sent through the 865 km-long pipeline to South Africa, and is consumed in a Sasol factory.
Approximately 3 MGJ is consumed in Mozambique per year (i.e., approximately 3 MGJ per annum in
the Matola area (by Mozal and others) and 0.3 MGJ each year in the Vilankulo and Inhassoro areas
close to a gas field (80% of which is for EDM power generation).

Figure 7.1-2 shows yearly gas production in Mozambique and Figure 7.1-3 shows investment in the
oil and gas sector.

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(Source: Institudo Nacional de Petroleos (“INP”, in English – National Petroleum Institute)

Figure 7.1-2 Yearly Gas Production in Mozambique

Investimento no sector Petrolífero

900
800
700
Milhões dolares

600
500
400
300
200
100
0
2004 2005 2006 2007 2008 2009
Ano

Investimento (Milhões de Dolares)

(Source: Ministry of Mineral Resources (“MMR”))

Figure 7.1-3 Investment in the Oil and Gas Sector

7.2 Gas Supply in the South

7.2.1 Gas Production Volume and Route

In 2004, a gas pipeline leading from the Pande and Temane gas fields of Mozambique to Secunda of
South Africa (ROMPCO pipeline, where a 50% interest is owned by the Government of Mozambique
(ENH) and the Government of South Africa (iGas), and the remaining 50% interest by Sasol of South
Africa) was constructed and was put into commercial operation (refer to Figure 7.2-1). This pipeline
has a total length of 865 km with a diameter of 660 mm. The current gas feed capacity is
approximately 150 MGJ per annum, which can be increased to 240 MGJ per annum by installation of
additional compressor stations. The production volume in the Pande and Temane gas fields for fiscal
2011 (July 2010 to June 2011) was approximately 130 MGJ per annum. According to the MMR report
of January 2012, the production volume for 2012 is anticipated to reach the level of 149 MGJ per
annum. The pipeline from the Pande and Temane gas fields to Secunda is provided with five takeoff
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points (also called tap-off points) in Mozambique; however, only the Ressano Garcia takeoff point of
Maputo province was working as of 2011, and in the current stage, a detailed usage plan of the
Chokwa takeoff point is being developed.

In 2006, construction of a pipeline was completed from the takeoff point of Ressano Garcia close to
the national boundary with South Africa to Matola city. This pipeline is currently in commercial
service. This pipeline is run by the Matola Gas Company (“MGC”), established as a joint venture
between ENH and private capital. The current gas demand in Matola city comes mainly from the
Mozal aluminum smelter plant and Ciementos de Mozambique (cement plant), and amounts to
approximately 3 MGJ per annum. This demand is expected to grow due to a firm increase in the future
demand for switching from petroleum over to gas in the Industrial Park in the suburbs of Maputo city
(Vidreira (glass industry) and CDM (beverage manufacturer)), and due to the gas demand for
household (residential) use and for power generation.

(Source: ENH)

Figure 7.2-1 TemaneSecunda Gas Pipeline Route

7.2.2 Gas Supply Volume

Extension work of the central processing facility (“CPF”) at the Pande and Temane gas fields has
already been completed in 2012 and the gas supply volume of the ROMPCO gas pipeline has also
been increased from 120 MGJ/year to 183 MGJ/year.

The maximum gas supply volume of the ROMPCO gas pipeline is 240 MGJ/year. The pipeline still
has a surplus capacity of 57 MGJ/year since the expansion work was completed. However, further
expansion work is not planned.
Gas Sales Agreement One (“GSA 1”)
1) 120 MGJ per annum (for South Africa)

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Gas Sales Agreement Two (“GSA 2”)

2) 27 MGJ per annum (for South Africa)
3) 27 MGJ per annum (for domestic power generation and other consumers (residential,
commercial, industrial and natural gas vehicle (“NGV”))
Royalty paid to the Government of Mozambique
4) Approx. 9 MGJ per annum (= 120 x 5% + (27 + 27) x 6%)

Total: 183 MGJ per annum

The Government of Mozambique retains the right to receive approximately 9 MGJ per annum as
royalties in 2014 and onward; the volume currently received (amount of gas consumed domestically)
amounts to 3 to 4 MGJ per annum (with the remainder received in cash). In the National Strategy for
the Development of the Natural Gas Market in Mozambique (Resolution No. 64/2009) published in
2009, the Government of Mozambique expressed a plan to supply, on a priority basis, royalty gas to
the projects that would contribute to economic development in Mozambique and whose profitability
cannot easily be ensured on a purely commercial basis.

The gas volume for domestic power generation described in 3) above is broken down into: (1) 6 MGJ
per annum for power generation for EDM and other consumers (residential, commercial, industrial)
and NGV, (2) 11 MGJ per annum for power generation for an IPP at Ressano Garcia (by
Gigawatt-Mozambique), and (3) 10 MGJ per annum for another IPP at Ressano Garcia (by Sasol New
Energy and EDM). At present, there are ongoing negotiations between ENH and EDM on the
agreement for the supply of the above-mentioned 6 MGJ per annum.

7.2.3 Gas Supply Route in the South

Gas is branched off at the Pressure Reducing Station (“PRS 1”) at Ressano Garcia, where the gas
pressure is reduced from 100 to 40 bars, and is fed to the Pressure Reducing Station (“PRS 2”) located
in Matola city, where the pressure is further reduced to 10 bar. After that, gas is supplied to users in
Matola city. Figure 7.2-2 illustrates the existing pipeline route.

(Source: ENH)

Figure 7.2-2 MGC Gas Pipeline Route

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The following are the basic specifications of the pipeline from Ressano Garcia to the PRS 2.
1) Pipe diameter: 8" (200 mm)
2) Total length: Approx. 68 km
3) Gas feed capacity: 40,000 m3/h at 25C, 1 atm (currently in operation at 12,000 m3/h)
4) Maximum allowable gas pressure: 70 bar (currently in operation at 40 bar)
At present, 10-bar gas is supplied from the PRS 2 of Matola city to gas users through a 22 km-long
piping network. Most (92%) of the gas supplied is consumed by the Mozal aluminum smelter plant
and Ciementos de Mozambique (cement plant). Figure 7.2-3 illustrates the existing gas pipeline
network in Matola city.

(Source: Prepared by the JICA Study Team based on ENH data)

Figure 7.2-3 Existing Gas Pipeline Network (green) in Matola City

It has been decided that ENH and KOGAS will jointly implement the natural gas pipeline project in
the Matola area. The preparation work for the project has already started (see Figure 7.2-4). Gas
pipeline work will begin from March 2013 and will be completed by January 2014. Since EDM has
confirmed that this project includes pipeline work to CTM site, it is not necessary to include the
pipeline work to the new Maputo power plant in the Japanese ODA project. In this case, gas pressure
in the MGC pipeline upstream will be decreased from 40 to 25 bars to meet the increase in gas
demand by laying new pipeline. Figure 7.2-4 illustrates the new pipeline route (from the branch point
situated 1.8 km upstream of the existing PRS-2 to CTM site) and Figure 7.2-5 illustrates the gas
pipeline route near the CTM site and the location of a new pressure reducing station in CTM site.

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(Source: EDM)

Figure 7.2-4 Preparation Work of New Pipeline Linking MGC Pipeline

and CTM (ENH/KOGAS)

Branch point

CTM

(Source: ENH)

Figure 7.2-5 Route of New Pipeline Linking MGC Pipeline

and CTM (ENH/KOGAS)

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(Source: ENH)

Figure 7.2-6 Pipeline Route near CTM and Location

of Pressure Reducing Station in CTM

7.2.4 Gas Supply Volume to the Gas-fired Thermal Power Plant in the Southern Region

Gas for the new gas pipeline mentioned above is planned to supply gas to the power plants owned by
EDM and customers in Maputo city. It is expected that the available gas volume would be 6.0
MGJ/year (2.8MGJ/y for CTM and 3.2MGJ/y for Beluluane) However, it is confirmed that gas of 5.8
MGJ/y will be supplied to EDM in contract agreement. Figure 7.2-7 shows the overall gas flow
schematic in the Southern region. The broken line indicates the pipeline to be installed in the future.
The values enclosed in parentheses indicate the future gas volumes.

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Buzi Mozanbigue Basin

14 Bcf

Pande Inhassoro
2.321 Tcf
ROMPCO
100 bar Temane
865 km/660φ 0.618 Tcf
Capacity
164 MGJ/y ～ Current production
240 MGJ/y 183 MGJ/y 0.25 ～ EDM 80%
0.3 MGJ/y Elgas 16%
Domestic 4%
Funhalouro
① ＋ ② = 6 MGJ/y

Vidreira

CDM
②
Chokue Residential
(Macarretane)
EDM NG Vehicles
①
CTM new gas fired CC
11.2km PRS
250φ
Magude IPP (*1) 25 bar PRS
11 MGJ/y MOZAL

Ciementos de Moçambique 92%

IPP (*2)
10 MGJ/y Others 8%
PRS 2
Ressano Garcia PRS 1 3 MGJ/y(*3) 3 MGJ/y
Matola
Mozambique
Pipe length 531 km MGC MGC
40 bar 10 bar
68 km/200φ Distribution lines
22km
South Africa
Pipe length 334 km

Capacity
Ｓｅｃｕｎｄａ 147 MGJ/y Sasol's petrochemical factories
(South Africa)

(*1) IPP at Ressano Garcia by GigaWatt-Mozambique

(*2) IPP at Ressano Garcia by Sasol New Energy and EDM
(*3) Current consumption rate
(*4) Refer to 4.3.3 (2)
(Source: Prepared by the JICA Study Team based on information and data obtained from ENH)

Figure 7.2-7 Overall Gas Flow Schematic in the Southern Region

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Figure 7.2-8 shows the organization structure for gas production and pipeline operations of
Pande-Temane Gas Fields.

ENH

iGas

25% 25% 50%

ROMPCO

(Source: World Bank)

Figure 7.2-8 Organization Structure for Gas Production and Pipeline Operations of
Pande-Temane Gas Fields

7.3 Gas Price

EDM is now negotiating with Maputo Gas Company (“MGC”) about a gas supply agreement and with
ENH about a gas transportation agreement. It seems that both contracts will be made by March 2013.

Gas price is assumed to be 5.6 USD/MGJ for CTM and 5.2 USD/MGJ for Beluluane. The difference
of gas prices between CTM and Beluluane is the length of the gas pipeline.

Gas prices are calculated based on the below table.

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Table 7.3-1 Gas Price Structure

(Source: EDM)

7.4 Relationship of Relevant Organization related to Gas Supply and Transport Agreements

Figure 7.4-1 shows the relationship of the relevant organizations related to the gas supply and
transport agreements.

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Gas Supply Agreement Gas Transport Agreement

EDM

Operation Agreement
MGC ENH-KOGAS, SA
Project Owner

Gas Purchase Agreement 20% Equity 80% Equity

ENH KOGAS

ENH
EPC (contractor)
Contractor
Kogas Mozambique (SPC)

SPT ROMPCO
E: Engineering P: Procurement C: Construction
Byudsan Daejoo ENT cop Sub-Contractor
Engineering
Gas Supply Agreement Gas Transport Agreement

Project of Gas Distribution for Maputo & Marracuene

Note:
ENH-KOGAS, SA (new company 30% ENH + 70% KOGAS from Korea): It will transport 5.8 MGJ/y of gas from Matola to Maputo & Marracuene via CTM and will tap the existing MGC pipeline in Matola
Empresa National de Hidrocarbonetos, EP (ENH) – Public company and arm of the government in the petroleum sector which has the allocation of 6 MGJ/y for EDM Power Generation at CTM and for Maputo and Marracuene
Korea Gas Corporation (“KOGAS”) – One of the world’s largest LNG importers, executing with ENH a new project for the construction of a gas pipeline and operating facility to supply gas to Maputo and Marracuene using the build-operate-transfer (“BOT”)
method
Kogas Mozambique: New Mozambican company and KOGAS have majority equity and acting as an EPC company for the construction of the new ENH-KOGAS, SA pipeline from Matola to Maputo and Marracuene
Matola Gas Company, SA (“MGC”): . Private company, has the pipeline from Ressano Garcia to Matola, and provides around 3 MGJ/y to the industrial area at Beluluane and Matola area and will supply 5.8 MGJ/y to EDM
Sasol Petroleum Temane Limitada (“SPT”): Responsible for production activities from the Pande and Temane field reservoirs
Rompco: Has the pipeline property from Temane to Secunda in South Africa and provides five take-off points in Mozambique and only Ressano Garcia Take-off point working at the moment
(Source：EDM)

Figure 7.4-1 Gas Supply & Transport Concept to EDM

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7.5 Scope of Gas Pipeline Work and Tie-in Point

As mentioned in the previous item, the gas pipeline works and pressure reducing stations (“PRSs”) are
the scope of supply of ENH/KOGAS. The tie-in point at PRS in CTM between EDM and
ENH/KOGAS is an outlet valve of PRS in CTM.

Currently, the gas pressure at PRS of CTM is approximately 25 bar. In this case, it is not necessary to
treat gas for GT through PRS because the required gas pressure at the GT nozzle inlet is 40 bar for
LM6000 and 26 bar for H25, respectively. After PRS, a gas compressor should be installed to boost
gas to the required gas pressure. In the meantime, if gas will be tapped before PRS2 and gas with more
than 60 bar gas pressure is obtained, it is not necessary to install a gas compressor after PRS in order
to reduce gas pressure.

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