User Guide

Greenhouse Gas Emissions Calculator

March 2025

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1. Background and Objectives
The Hong Kong University of Science and Technology cooperated with the Green and
Sustainable Finance Cross-Agency Steering Group to build two greenhouse gases
(GHG) emissions tools in bridging the data gap highlighted by the industry.

The GHG emissions calculator aims to facilitate corporates to calculate their Scopes 1
and 2 GHG emissions (as classified in the GHG Protocol Corporate) based on their
levels of actual activities and the widely adopted international standards, such as the
GHG Protocol Corporate Accounting and Reporting Standard. To cater the needs of
local users, this GHG emissions calculator incorporates more parameters in Hong
Kong and the Mainland, please refer to section 2.4 for details.

2. Introduction to the GHG Emissions Calculator

2.1 Standards and Guidelines
The GHG emissions calculator is built with reference to widely adopted
international standards as well as local standard to address direct and indirect
emissions of CO2, CH4, N2O, HFC and PFC in scopes 1 and 2.

International standards:
• WBCSD/WRI1: The GHG Protocol Corporate Accounting and Reporting
Standard (Revised Edition)
• ISO 14064-1 (2018): Greenhouse Gases – Part 1: Specification with
guidance at the organization level for quantification and reporting of
greenhouse gas emissions and removals

Local standard:
• HKEPD2 and EMSD3 Guidelines: Guidelines to Account for and Report on
Greenhouse Gas Emissions and Removals for Buildings (Commercial,
Residential or Institutional Purposes) in Hong Kong (2010 Edition)

1
World Business Council for Sustainable Development and World Resources Institute
(WBCSD/WRI)
2
Hong Kong Environmental Protection Department (HKEPD)
3
Electrical and Mechanical Services Department (EMSD)

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 These standards categorize various parameters into 3 different scopes to
facilitate the accounting of greenhouse gases.

Scope 1 Scope 2 Scope 3

Direct emissions and Indirect emissions: Other indirect emissions:
removals: • Imported energy • Water and sewage
• Stationary such as purchased • Waste disposal
combustion electricity and • Air travels
• Mobile towngas • Others
combustion
• Fugitive emission
• Other physical and
chemical
processing

2.2 Boundary Setting

Users are suggested to make reference to “WBCSD/WRI: The GHG Protocol
Corporate Accounting and Reporting Standard” and adopts the control
approach in the determination of organizational boundary.

Fig.1 Summary of different approaches to define the organizational boundaries (Zhou, 2020)

2.3 Calculation Methodology

The calculation methodology of the GHG emissions calculator is based on the
following equations as recommended in the HKEPD and EMSD GHG
guidelines for Scopes 1 and 2 GHG emissions.

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 2.3.1 Scope 1 Direct Emissions and Removals
(i) GHG Emissions from Stationary Combustion Sources

𝐸𝑚𝑖𝑠𝑠𝑖𝑜𝑛 (𝐶𝑂2 ) = ∑ 𝐹𝑢𝑒𝑙 𝑐𝑜𝑛𝑠𝑢𝑚𝑝𝑡𝑖𝑜𝑛 × 𝐸𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟 𝑜𝑓 𝐶𝑂2

Where
Emission is measured in tonnes of CO2-equivalent;
The amount of fuel used is measured either by its volume, such as liters, or by
its mass, such as kilograms; and
CO2 Emission Factor = Net Calorific Value of Fuel x Carbon Emission Factor of
Fuel x Fraction of Carbon Oxidized x (44/12)

This equation calculates the emissions of CH4 and N2O:

𝐸𝑚𝑖𝑠𝑠𝑖𝑜𝑛 (𝐶𝐻4 /𝑁2 𝑂)

= ∑ 𝐹𝑢𝑒𝑙 𝑐𝑜𝑛𝑠𝑢𝑚𝑝𝑡𝑖𝑜𝑛 × 𝐸𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟 𝑜𝑓(𝐶𝐻4 / 𝑁2 𝑂)

× 𝑅𝑒𝑙𝑎𝑡𝑖𝑣𝑒 𝐺𝑊𝑃

where
Emission is measured in tonnes of CO2-equivalent;
Amount of fuel consumed is in terms of volume (e.g. litre) or mass (e.g. kg) for
particular fuel;
Emission Factor of (CH4 / N2O) = Net Calorific Value of the Fuel x Specific (CH4 /
N2O) x Conversion Factor; and
Relative GWP refers to the Relative Global Warming Potential of CH4 or N2O

Global warming potential (GWP) for CO2, CH4 and N2O

GHGs GWP 100-year time horizon
Fifth Assessment Report Sixth Assessment Report
(AR5) (IPCC, 2014) (AR6) (IPCC, 2021)
CO2 1 1
CH4 28 27
N 2O 265 273
(Greenhouse Gas Protocol, n.d.)

The GHG emissions calculator uses the latest available GWP values from the
IPCC4 based on the starting date of your reporting period. For example, if your
reporting period begins on 1 January 2021 or later, the GWP values from the
IPCC AR6 will be applied in the GHG emissions calculator.

4
The Intergovernmental Panel on Climate Change (IPCC)

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 Please refer to section 2.4.1(i) for the emission factors for stationary
combustion.

(ii) GHG Emissions from Mobile Combustion Sources

The calculation covers three categories of mobile sources: road transport, air
transport, and water transport.

𝐸𝑚𝑖𝑠𝑠𝑖𝑜𝑛 (𝐶𝑂2 ) = ∑ 𝐹𝑢𝑒𝑙 𝑐𝑜𝑛𝑠𝑢𝑚𝑝𝑡𝑖𝑜𝑛 × 𝐸𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟 𝑜𝑓 𝐶𝑂2

Where
Emissions, measured in tonnes of CO2-equivalent, are calculated by summing
up the emissions from all fuel types, transport modes, and vehicle categories;
Fuel consumption, measured in volume (e.g. liters), is determined for each
specific fuel type, transport mode, and vehicle category; and
CO2 Emission Factor = Net Calorific Value of Fuel x Carbon Emission Factor of
Fuel x Fraction of Carbon Oxidized x (44/12)

This equation calculates the emissions of CH4 and N2O:

𝐸𝑚𝑖𝑠𝑠𝑖𝑜𝑛 (𝐶𝐻4 /𝑁2 𝑂)

= ∑ 𝐹𝑢𝑒𝑙 𝑐𝑜𝑛𝑠𝑢𝑚𝑝𝑡𝑖𝑜𝑛 × 𝐸𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟 𝑜𝑓(𝐶𝐻4 / 𝑁2 𝑂)

× 𝑅𝑒𝑙𝑎𝑡𝑖𝑣𝑒 𝐺𝑊𝑃

where
Emissions, measured in tonnes of CO2-equivalent, are calculated by summing
up the emissions from all fuel types, transport modes, and vehicle categories;
Fuel consumption, measured in volume (e.g. liters), is determined for each
specific fuel type, transport mode, and vehicle category;
Emission Factor of (CH4 / N2O) = Net Calorific Value of the Fuel x Specific (CH4 /
N2O) x Conversion Factor; and
Relative GWP refers to the Relative Global Warming Potential of CH4 or N2O

Please refer to section 2.4.1(ii) for the emission factors for mobile combustion.

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 (iii) HFC and PFC Emissions for Refrigeration / Air-conditioning (Fugitive
Emission)

𝑂𝐸 = ∑(𝐶𝑠 + 𝐶𝑖 − 𝐶𝑑 − 𝐶𝑒 )𝑗 × 𝐺𝑊𝑃𝑗

Where:
OE = CO2-equivalent emissions resulting from the release of refrigerant j during
the operation of equipment
Cs = The inventory of refrigerant in storage (kg) at the beginning of the
reporting period
Ci = The amount of refrigerant added to the inventory during the reporting
period (kg)
Cd = The amount of refrigerant that was disposed of through environmentally
responsible means (such as recycling) during the reporting period (kg)
Ce = The inventory of refrigerant in storage, measured in kilograms, at the end
of the reporting period
GWP = The 100-year Global Warming Potential (GWP) of refrigerant j, can be
obtained using Table 3.

Please refer to section 2.4.1(iii) for the GWP of refrigerants.

2.3.2 Scope 2 Energy Indirect Emissions

Energy Indirect GHG Emissions due to Electricity and Towngas Purchased

𝐺𝐻𝐺 𝐸𝑚𝑖𝑠𝑠𝑖𝑜𝑛
= 𝑄𝑢𝑎𝑛𝑡𝑖𝑡𝑦 𝑜𝑓 𝑝𝑢𝑟𝑐ℎ𝑎𝑠𝑒𝑑 𝑒𝑙𝑒𝑐𝑡𝑟𝑖𝑐𝑖𝑡𝑦/𝑡𝑜𝑤𝑛𝑔𝑎𝑠
× 𝐸𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝐹𝑎𝑐𝑡𝑜𝑟

Please refer to section 2.4.2 for the emission factors for purchased electricity
and towngas.

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 2.4 Emission Factors
The results of the calculations will be expressed in terms of CO2-equivalent
(CO2-e).

2.4.1 Scope 1 - Direct Emissions

The tables of emission factors for stationary combustion and mobile
combustion presented below are extracted from two sources:

• the EMSD/EPD Guidelines to Account for and Report on Greenhouse Gas

Emissions and Removals for Buildings In Hong Kong (2010), and

• the Guidance for Quantification and Reporting of the Organization's

Greenhouse Gas Emissions in Shenzhen (深圳市标准化指导性技术文件 -
组织的温室气体排放量化和报告指南) (2018).

i) Stationary Combustion Sources in Hong Kong

Table 1-1 CO2 Emission factor by fuel type
Fuel Type Emission Factor Unit

Diesel Oil 2.614 kg/litre

LPG 3.017 kg/kg

Kerosene 2.429 kg/litre

Charcoal 2.970 kg/kg

Towngas 2.549 kg/unit

Table 1-2 CH4 Emission factor by fuel type

Fuel Type Emission Factor Unit

Diesel Oil 0.0239 g/litre

LPG 0.0020 g/kg

Kerosene 0.0241 g/litre

Charcoal 5.5290 g/kg

Towngas 0.0446 g/unit

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 Table 1-3 N2O Emission factor by fuel type
Fuel Type Emission Factor Unit

Diesel Oil 0.0074 g/litre

LPG 0.0000 g/kg

Kerosene 0.0076 g/litre

Charcoal 0.0276 g/kg

Towngas 0.0099 g/unit

Stationary Combustion Sources in Mainland

Table 1-4 CO2 Emission factor by fuel type
Fuel Type Fuel Type (Chinese) Emission Factor Unit

Anthracite 無煙煤 1.97 kgCO2/kg

Bituminous coal 煙煤 1.86 kgCO2/kg

Lignite 褐煤 2.06 kgCO2/kg

Washed coal 洗精煤 2.45 kgCO2/kg

Middling coal 洗中煤 0.78 kgCO2/kg

Slime 煤泥 1.17 kgCO2/kg

Coke 焦炭 2.85 kgCO2/kg

Crude oil 原油 3.02 kgCO2/kg

Fuel oil 燃料油 3.17 kgCO2/kg

Petrol 汽油 2.92 kgCO2/kg

Kerosene 一般煤油 3.03 kgCO2/kg

Diesel oil 柴油 3.1 kgCO2/kg

LNG 液化天然氣 2.58 kgCO2/kg

LPG 液化石油氣 3.1 kgCO2/kg

Refinery dry gas 煉廠乾氣 3.04 kgCO2/kg

Ethane 乙烷 3.28 kgCO2/kg

Bitumen 瀝青 3.26 kgCO2/kg

Lubricating oil 潤滑油 3.04 kgCO2/kg

Petroleum coke 石油焦 4.14 kgCO2/kg

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 Natural gas 天然氣 0.0022 kgCO2/L

Coke oven gas 焦爐煤氣 0.00089 kgCO2/L

Blast furnace gas 高爐煤氣 0.00017 kgCO2/L

Producer gas fuel 發生爐煤氣 0.00023 kgCO2/L

Heavy oil catalytic 重油催化裂解煤氣 0.00085 kgCO2/L

cracking gas
Heavy oil thermal 重油熱裂解煤氣 0.0016 kgCO2/L
cracking gas
Coke gas 焦炭製氣 0.00072 kgCO2/L

Coalbed methane 壓力水化煤氣 0.00067 kgCO2/L

Water gas 水煤氣 0.0046 kgCO2/L

Biomass Combustion Sources in Mainland

Table 1-5 CO2 Emission factor
Fuel Type Fuel Type Emission Unit
(Chinese) Factor
Timber/ waste wood 木材/廢木材 2.21 kgCO2/kg

Other solid biomass 其他固體生物量 2.7 kgCO2/kg

ii) Mobile Combustion Sources in Hong Kong

Table 2-1 CO2 Emission factor
Fuel Type Emission Factor Unit

Diesel Oil (DO) 2.614 kg/litre

Unleaded Petrol (ULP) 2.360 kg/litre

Liquefied Petroleum Gas (LPG) 1.679 kg/litre

3.017 kg/kg

Gas Oil (For Ships only) 2.645 kg/litre

Kerosene (Including Jet Kerosene) 2.429 kg/litre

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 Table 2-2 CH4 Emission factor

Vehicle Type Fuel Type Emission Factor Unit

Motorcycle ULP 1.422 g/litre

Passenger Car ULP 0.253 g/litre

DO 0.072 g/litre

Private Van ULP 0.203 g/litre

DO 0.072 g/litre

LPG 0.248 g/litre

Public Light Bus DO 0.072 g/litre

LPG 0.248 g/litre

Light Goods Vehicle ULP 0.203 g/litre

DO 0.072 g/litre

Heavy Goods Vehicle DO 0.145 g/litre

Medium Goods Vehicle DO 0.145 g/litre

Ships Gas Oil 0.146 g/litre

Aviation Jet Kerosene 0.069 g/litre

Other Mobile Machinery DO 0.0239 g/litre

LPG 0.0036 g/litre

0.006 g/kg

Kerosene 0.0241 g/litre

Table 2-3 N2O Emission factor

Vehicle Type Fuel Type Emission Factor Unit

Motorcycle ULP 0.046 g/litre

Passenger Car ULP 1.105 g/litre

DO 0.110 g/litre

Private Van ULP 1.140 g/litre

DO 0.506 g/litre

LPG 0.000 g/litre

Public Light Bus DO 0.506 g/litre

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 LPG 0.000 g/litre

Light Goods Vehicle ULP 1.105 g/litre

DO 0.506 g/litre

Heavy Goods Vehicle DO 0.072 g/litre

Medium Goods Vehicle DO 0.072 g/litre

Ships Gas Oil 1.095 g/litre

Aviation Jet Kerosene 0.000 g/litre

Other Mobile Machinery DO 0.007 g/litre

LPG 0.000 g/litre or g/kg

Kerosene 0.0076 g/litre

Mobile Combustion Sources in Mainland

Table 2-4 CO2 Emission factor
Transport Fuel Type Fuel Type Emission Unit
(Chinese) Factor
Road transport Petrol 汽油 2.92 kgCO2/kg

Kerosene 噴氣煤油 3.02 kgCO2/kg

Diesel oil 柴油 3.1 kgCO2/kg

LPG 液化石油氣 3.1 kgCO2/kg

LNG 液化天然氣 2.68 kgCO2/kg

Non-road Petrol 汽油 2.92 kgCO2/kg

transport
Diesel oil 柴油 3.1 kgCO2/kg

iii) Fugitive emission

This GHG emissions calculator include the refrigerants by making reference to
the EMSD/EPD Guidelines to Account for and Report on Greenhouse Gas
Emissions and Removals for Buildings in Hong Kong, the Greenhouse Gas
Protocol (n.d.) and the California Air Resources Board (n.d.). The global warming
potential (GWP) of these refrigerants are updated to reflect the most recent data
available from the IPCC AR5 and AR6.

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Table 3 GWP of Refrigerants

Refrigerant Type AR5 AR65 Refrigerant Type AR5 AR65

HCFC-21 148 160 PFC-41-12 8,550 9,220
HCFC-22 1,760 1,960 PFC-51-14 7,910 8,620
HCFC-123 79 90 R-401A 1,130 1,263
HCFC-124 527 597 R-401B 1,236 1,381
HCFC-141b 782 860 R-401C 876 982
HCFC-142b 1,980 2,300 R-402A 2,571 2,989
HCFC-225ca 127 137 R-402B 2,261 2,597
HCFC-225cb 525 568 R-403B 4,457 4,721
HFC-23 12,400 14,600 R-404A 3,943 4,728
HFC-32 677 771 R-406A 1,780 2,021
HFC-41 116 135 R-407A 1,923 2,262
HFC-43-10mee 1,650 1,600 R-407B 2,547 3,001
HFC-125 3,170 3,740 R-407C 1,624 1,908
HFC-134 1,120 1,260 R-407D 1,487 1,748
HFC-134a 1,300 1,530 R-407F 1,674 1,965
HFC-143 328 364 R-407H 1,378 1,615
HFC-143a 4,800 5,810 R-408A 3,257 3,856
HFC-152 16 22 R-409A 1,485 1,670
HFC-152a 138 164 R-410A 1,924 2,256
HFC-161 4 5 R-410B 2,048 2,404
HFC-227ea 3,350 3,600 R-411A 1,555 1,733
HFC-236cb 1,210 1,350 R-411B 1,659 1,847
HFC-236ea 1,330 1,500 R-414B 1,274 1,431
HFC-236fa 8,060 8,690 R-416A 975 1,139
HFC-245ca 716 787 R-417A 2,127 2,508
HFC-245fa 858 962 R-417C 1,643 1,935
HFC-365mfc 804 914 R-420A 1,382 1,622
PFC-14 6,630 7,380 R-500 7,564 9,268
PFC-116 11,100 12,400 R-502 4,786 5,872
PFC-218 8,900 9,290 R-503 13,300 15,560
PFC-318 9,540 10,200 R-507 3,985 4,775
PFC-31-10 9,200 10,000 R-508B 11,698 13,412

5
For refrigerant types R, their GWP under AR 6 are projected by referencing to the GWP of
their constituent refrigerants proportionally as describe by the California Air Resources Board
(n.d.).

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 2.4.2 Scope 2 – Indirect emissions: Purchased Electricity and Towngas
The emission factors for purchased electricity from HKE and CLP are sourced
from their annual sustainability reports, while the territory-wide default value
for Hong Kong is suggested by the EMSD/EPD Guidelines to Account for and
Report on Greenhouse Gas Emissions and Removals for Buildings in Hong Kong
(2010).

The electricity emission factors for Mainland are sourced from the 2019
Emissions Reduction Project Baseline Emission Factor for the Chinese Regional
Power Grid (2019 年度減排專案中國區域電網基準線排放因數) and 2021
Electricity Carbon Dioxide Emission Factor (2021 年電力二氧化碳排放因數). In
addition, the 2022 country-wide emission factor for Mainland that published by
The Ministry of Ecology and Environment of People’s Republic of China in
February 2023 is also included in the data set.

The towngas emission factor is from the annual Environmental, Social and
Governance Report of Towngas.

It is important to note that the GHG emissions calculator will use the latest
available emission factors based on the starting date of your reporting period.
For example, if your reporting period begins between 1 January 2022 and 31
December 2022, the emission factors for the year 2022 will be used. In cases
where emission factors are updated less frequently, such as the emission
factors of purchased electricity in Mainland, the emission factors for the year
2021 will be used, as they are the latest emission factors available based on the
reporting period’s starting date.

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Table 4-1 Emission factor of purchased electricity in Hong Kong and Mainland

Location Electricity Unit Emission Factor6

Company/ 2020 2021 2022 2023
Power Grid
Hong Kong HKE kg/kWh 0.71 0.71 0.68 0.66

Hong Kong CLP kg/kWh 0.37 0.39 0.39 0.39

Hong Kong Territory-wide kg/kWh 0.7

Mainland Northern kg/kWh 0.9419 0.712

China Grid
Mainland Northeast kg/kWh 1.0826 0.6012
China Grid
Mainland Eastern China kg/kWh 0.7921 0.5992
Grid
Mainland Central China kg/kWh 0.8587 0.5354
Grid
Mainland Northwest kg/kWh 0.8922 0.5951
China Grid
Mainland Southern kg/kWh 0.8042 0.4326
China Power
Grid
Mainland Southwest kg/kWh 0.8587 0.2113
China Power
Grid7
Mainland Country-wide kg/kWh 0.5568 0.5703

6
Cells that are left blank indicate that no latest emission factors are available for the corresponding
years.
7
In the 2021 Electricity Carbon Dioxide Emission Factor Calculation Guideline (2021 年電力二氧化碳
排放因數計算說明), Sichuan province and Chongqing city, which were previously categorized under
the Central China Grid, have been reclassified to the Southwest China Power Grid. As there is no
publicly available information on the emission factor of these two places prior to 2021, the emission
factor of Central China Grid was hence applied retrospectively as the emission factor of the Southwest
China Power Grid for the year 2020.

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Table 4-2 Geographical area covered in the regional power grid of Mainland8
Power Grid Covering Provinces and Cities

North China Grid Beijing city, Tianjin city, Hebei province, Shanxi province,
華北區域電網 Shandong province, Inner Mongolia autonomous region (except
for Chifeng city, Tongliao city, HulunBuir city and Hinggan League)
北京市、天津市、河北省、山西省、山東省、蒙西（除赤峰
市、通遼市、呼倫貝爾市和興安盟外的內蒙古其他地區）
Northeast China Liaoning province, Jilin province, Heilongjiang province, Inner
Grid Mongolia autonomous region (Chifeng city, Tongliao city,
東北區域電網 HulunBuir city and Hinggan League)
遼寧省、吉林省、黑龍江省、蒙東（赤峰市、通遼市、呼倫
貝爾市和興安盟）
East China Grid Shanghai city, Jiangsu province, Zhejiang province, Anhui
華東區域電網 province, Fujian province
上海市、江蘇省、浙江省、安徽省、福建省
Central China Grid Henan province, Hubei province, Hunan province, Jiangxi province
華中區域電網 河南省、湖北省、湖南省、江西省
Northwest China Shaanxi province, Gansu province, Qinghai province, Ningxia
Grid autonomous region, Xinjiang autonomous region
西北區域電網 陝西省、甘肅省、青海省、寧夏自治區、新疆自治區
China Southern Guangdong province, Guangxi autonomous region, Yunnan
Power Grid province, Guizhou province, Hainan province
南方區域電網 廣東省、廣西自治區、雲南省、貴州省、海南省
China Southwest Sichuan province, Chongqing city
Power Grid 四川省、重慶市
西南區域電網

Table 5 Emission factor of purchased towngas

Location Towngas Unit Emission Factor
Company
2020 2021 2022 2023
Hong Towngas kg/kWh 0.592 0.588 0.576 0.549
Kong

8
The distribution of geographical area within the regional power grid of Mainland is based on the
latest 2021 Electricity Carbon Dioxide Emission Factor Guideline (2021 年電力二氧化碳排放因數計
算說明) published by The Ministry of Ecology and Environment of People’s Republic of China in April
2024.

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3. How to use the GHG Emissions Calculator

The GHG emissions calculator is an online tool with clear guidance, the icons
in the tool also provide simple guidance for respective input field. Please read
below for details on using the GHG emissions calculator.

You can create an account or log in to save your inputs and calculation results,
please refer to section 3.5 for the functions of the account platform. You can also
proceed as guest but your inputs and the calculation results will not be saved.

3.1 Selecting the location of business operations and reporting period

On the front page of the GHG emissions calculator, select the applicable
location(s) of business operations of the company. You can select more than 1
location.

Then, you can enter the reporting period which can be up to 12 months. The
GHG emissions calculator is designed to quantify GHG emissions of a
company by integrating emission factors from the year 2020 onwards,
therefore, please enter a starting date that is on or after 1 January 2020.

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 It is important to note that the GHG emissions calculator will use the latest
available emission factors based on the starting date of your reporting period.
For example, if your reporting period begins between 1 January 2022 and 31
December 2022, the emission factors for the year 2022 will be used, provided
that these emission factors are update annually. If the emission factors are
updated less frequently, the latest available data based on the starting date of
the reporting period will be used. For example, for purchased electricity in
Mainland, the emission factors for the year 2021 will be used, as no emission
factors for year 2022 have been published.

If you do not specify the reporting period, the calculator will use the most
recent emission factors for the calculation by default.

3.2 Inputting Scope 1 data

On the Scope 1 page, you can input fuel consumptions by i) stationary
combustion, ii) mobile combustion and iii) fugitive emission, where
applicable. If Scope 1 emission is not applicable to the company, you can
press “Next” to proceed to Scope 2 inputs.

i) Stationary combustion
You can enter the fuel consumption by each station or by aggregating the
consumption of all stations by each fuel type.

The name of the “station” field is defaulted as Station 1, you can change the
name of the station to label a designated station and its corresponding fuel
consumption for easy reference.

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 Then you can select a fuel type in the drop-down menu and input the fuel
consumption. The GHG emissions calculator does not cover all possible

measurement units, you may refer to icon for a unit conversion table
which may be helpful for performing unit conversion.

To add more stations, you can press the “add more station”. To remove any

additional station, click the icon.

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 ii) Mobile combustion
Similar with stationary combustion, you can enter the fuel consumption by
each vehicle or by aggregating the consumption of the same type of vehicles
by each fuel type.

You can change the name of the vehicle to label a designated vehicle and its
corresponding fuel consumption. Then you can select a fuel type in the drop-
down menu and input the fuel consumption.

iii) Fugitive emission

If you want to include fugitive emissions in the calculation, you can check the
box of “include fugitive emission in the calculation”.
While the calculator uses the latest GWP values available (i.e. AR6) for the
selected reporting period, you could select AR5 from the drop-down menu
and use the corresponding GWP values to calculate fugitive emissions for
inventory and reporting purposes.

Then you can select the refrigerant type and input the inventory balances,
purchase and disposal during the reporting period. The usage of the
refrigerants during the period will be automatically calculated based on your
input. Please note that any refrigerant used during the period should not be
less than zero.

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 If the company also has business operations in Mainland, repeat the steps for
inputting fuel consumption for stationary combustion, mobile combustion,
and fugitive emission, where applicable.

After inputting all applicable Scope 1 fields, press “Next” to proceed to Scope
2 section.

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 3.3 Inputting Scope 2 data
On the Scope 2 page, you can input fuel consumptions for i) purchased
electricity and ii) purchased towngas (for Hong Kong only), where applicable.

i) Purchased electricity
You can select the source of electricity in the drop-down menu and input the
corresponding electricity consumption in kWh.

ii) Purchased towngas (Hong Kong only)

You can input the towngas consumption in Hong Kong during the year, if
applicable.

In general, this figure should be the sum of towngas consumption of all

stations under Scope 1 emission. It is because the consumption of towngas
involves both types of emissions – (i) direct emissions (Scope 1) arising from
the combustion of towngas of the station and (ii) indirect emissions (Scope 2)
arising from the generation and transportation of towngas from the
production plant to the station concerned.

After inputting all applicable Scope 2 fields, press “Next” to proceed to the
calculation results.

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 3.4 Reviewing results and generating reports
On the results page, you can see a summary of your inputs and the
calculation results.

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 You can click the “Export to Excel” to download an excel report which
includes your inputs, emission factors applied, data sources, and calculation
results for your records.

In addition, you can click the “Generate a report” to download a GHG

emissions report in PDF format which shows details of the calculation
methodologies, emission factors applied, and the calculation results. The PDF
report aims to aid companies’ sustainability reporting processes. It is
designed to provide a clear and transparent calculation of GHG emissions,
thereby facilitating the audit and assurance of the calculation on the reported
GHG emissions by any third party agencies.

For generation of the PDF report, you need to enter the company name and
select the industry that is most applicable to the company. This information
will be shown in the PDF report for identification purposes. It is important to
note that by using the GHG emissions report function, you consent to the
CASG and HKUST to use the data and/or information provided on the “GHG
Emissions Calculator” for research and analysis purposes. Individual data will
be used solely for the development and enhancement of the GHG Emissions
Calculator and GHG Emissions Estimator, and will not be shared with any third
parties except as required by law.

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 3.5 Retrieving calculation results (only for users who created an account)
If you create an account and log in, your inputs and calculation results, as well
as the reports are automatically saved in the account platform.

To access your user profile and retrieve your calculation history, press “Non-
listed Company Disclosure Platform”.

Then click “History of Emissions Calculation” on the menu, your calculation

history will be shown. You can review the information online, or click the

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 icon and the icon to download the excel report and the PDF report
respectively.

To remove a calculation history, click the icon and confirm to delete.

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4. Reference
California Air Resources Board. (n.d.). High-GWP refrigerants. Retrieved from
https://ww2.arb.ca.gov/resources/documents/high-gwp-refrigerants
CLP Group. Sustainability Reports. Retrieved from
2020: https://www.clp.com.cn/wp-content/uploads/2021/04/CLP-Sustainability-
Report-2020.pdf
2021: https://www.clp.com.cn/wp-
content/uploads/2022/03/Sustainability_Report_2021_en.pdf
2022: https://www.clpgroup.com/content/dam/clp-
group/channels/sustainability/document/sustainability-
report/2022/CLP_Sustainability_Report_2022_en.pdf.coredownload.pdf
2023: https://www.clpgroup.com/content/dam/clp-
group/channels/sustainability/document/sustainability-
report/2023/CLP_Sustainability_Report_2023_en.pdf
Electrical and Mechanical Services Department and Environmental Protection
Department. (2010). Guidelines to Account for and Report on Greenhouse Gas
Emissions and Removals for Buildings in Hong Kong. Retrieved from
https://www.epd.gov.hk/epd/sites/default/files/epd/gn_pdf/GN2014P097-
2014c-e.pdf
Greenhouse Gas Protocol. (2024, August 7). Global Warming Potential Values.
Retrieved from
https://ghgprotocol.org/sites/default/files/2024-08/Global-Warming-Potential-
Values%20%28August%202024%29.pdf
IPCC. (2014). IPCC Fifth Assessment Report, Appendix 8. Retrieved from
https://ar5-syr.ipcc.ch/resources/htmlpdf/WG1AR5_Chapter08_FINAL/
IPCC. (2021). IPCC Sixth Assessment Report, Chapter 7 Supplementary Material 7.
Retrieved from
https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chap
ter07_SM.pdf
The Hongkong Electric Company Limited Sustainability Reports. Retrieved from
2020:https://www.hkelectric.com/documents/en/CorporateSocialResponsibility/Cor
porateSocialResponsibility_CDD/Documents/SR2020E.pdf
2021:https://www.hkelectric.com/documents/en/CorporateSocialResponsibility/Cor

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 porateSocialResponsibility_CDD/Documents/SR2021E.pdf
2022:https://www.hkelectric.com/documents/en/CorporateSocialResponsibility/Cor
porateSocialResponsibility_CDD/Documents/SR2022E.pdf
2023:https://www.hkelectric.com/documents/en/InvestorRelations/InvestorRelation
s_GLNCS/Documents/2024/ESR2023%20full%20version.pdf
The Hong Kong and China Gas Company Limited. Environmental, Social and
Governance Reports. Retrieved from
2020: https://www.towngas.com/getmedia/5b116b7f-c24b-4bb6-8d2c-
66457c5d9981/TowngasESGR2020_English_2.pdf.aspx?ext=.pdf
2021: https://www.towngas.com/getmedia/606f4b03-f911-4efc-b184-
9c5937736e84/Towngas_ESG2021_EN.aspx
2022: https://www.towngas.com/getmedia/c6da701c-519b-4e04-aee9-
7557b1d509f4/Towngas_ESG2022_EN.pdf.aspx
2023: https://www.towngas.com/getmedia/6b774b8d-c94b-4e39-8fda-
0e505cf6d10f/Towngas-ESG-Report-2023_EN.pdf.aspx?ext=.pdf
WBCSD/WRI. (2015). The GHG Protocol Corporate Accounting and Reporting
Standard
Zhou, S. W. W. (2020). Carbon Management for a Sustainable Environment (1st ed.
2020.). Springer International Publishing. https://doi.org/10.1007/978-3-030-35062-8
深圳市市场和质量监督管理委员会. (2018, November 15). 深圳市标准化指导性技
术文件 - 组织的温室气体排放量化和报告指南.
中華人民共和國生態環境部. (2020, December 29). 2019 年度减排项目中国区域
电网基准线排放因子. Retrieved from
https://www.mee.gov.cn/ywgz/ydqhbh/wsqtkz/202012/W0202012296103533
40851.pdf
中華人民共和國生態環境部. (2023, February 7). 关于做好 2023—2025 年发电行
业企业温室气体排放报告管理有关工作的通知. Retrieved from
https://www.mee.gov.cn/xxgk2018/xxgk/xxgk06/202302/t20230207_1015569.
html
中華人民共和國生態環境部. (2024, April 12). 生态环境部、国家统计局关于发布
2021 年电力二氧化碳排放因子的公告. Retrieved from
https://www.mee.gov.cn/xxgk2018/xxgk/xxgk01/202404/t20240412_1070565.
html

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