ENERGY

AUDIT
Energy Audit
 Definition of Energy Audit
• As per Indian Energy Conservation Act 2001,
Energy Audit is defined as:

“the verification, monitoring and analysis of use of

energy including submission of technical report
containing recommendations for improving energy
efficiency with cost benefit analysis and an action plan
to reduce energy consumption “
 Why the Need for Energy Audit
• The three top operating expenses are energy
(both electrical and thermal), labour and
materials.
• Energy would emerge as a top ranker for
cost reduction
• primary objective of Energy Audit is to determine
ways to reduce energy consumption per unit of
product output or to lower operating costs
• Energy Audit provides a “ bench-mark”
(Reference point) for managing energy in the
organization
 Types of Energy Audits

1. Preliminary Energy Audit

2. Targeted Energy Audit
3. Detailed Energy Audit
 Preliminary Energy Audit

• Preliminary energy audit uses existing or easily

obtained data
• Find out the energy consumption area in the
organization
• Estimates the scope for saving
• Identifies the most likely areas for attention
• Identifies immediate(no cost or low cost) improvements
• Sets a ‘reference point’
• Identifies areas for more detailed study/measurement
 Targeted Energy Audits

• Targeted energy audits are mostly based upon

the outcome of the preliminary audit results.
• They provide data and detailed analysis on
specified target projects.
• As an example, an organization may target its
lighting system or boiler system or compressed
air system with a view to bring about energy
savings.
• Targeted audits therefore involve detailed surveys
of the target subjects/areas with analysis of the
energy flows and costs associated with those
targets.
 Detailed Energy Audit

Detailed Energy Audit evaluates all systems and

equipment which consume energy and the
audit comprises a detailed study on energy
savings and costs.

Detailed Energy Audit is carried out in 3 phases

– The Pre-audit Phase
– The Audit Phase
– The Post-Audit Phase
 The Ten Steps for Detailed Audit

Step PLAN OF ACTION PURPOSE /

No RESULTS
Phase I –Pre Audit Phase

Step 1  Plan and organise  Resource planning, Establish/

 Walk through Audit organize a Energy audit team
 Informal Interview  Organize Instruments & time frame
with Energy Manager,  Macro Data collection (suitable to
Production type of industry.)
/ Plant Manager  Familiarization of process/plant activities
 First hand observation&
Assessment of current level operation
and practices
Step 2
 Conduct of brief  Building up cooperation
meeting /  Issue questionnaire for each department
awareness programme  Orientation, awareness creation
with all divisional
heads and persons
concerned (2-3 hrs.)
 Phase II –Audit Phase
Step 3  Primary data gathering,  Historic data analysis, Baseline data
Process Flow collection
Diagram, & Energy  Prepare process flow charts
Utility Diagram  All service utilities system diagram
(Example: Single line power distribution
diagram, water, compressed air & steam
distribution.
 Design, operating data and schedule of
operation
 Annual Energy Bill and energy consumption
pattern (Refer manual, log sheet, name plate,
interview)

Step 4  Conduct survey  Measurements :

and monitoring Motor survey, Insulation, and Lighting
survey with portable instruments for
collection of more and accurate data.
Confirm and compare operating data with
design data.
Step 5  Conduct of de t a i l e d  Tr i a l s / E x p e r i m e n t s :
trials - 2 4 h o u r s p o w e r m o n i t o r i n g ( M D , P F,
/experiments for k W h etc.).
se l e c t e d e n e r g y g u z z l e r s - L o a d v a r i a t i o n s t r e n d s i n p u m p s , fa n
c o m p r e s s o r s etc.
- B o i l e r / E ff i c i e n c y trials f o r ( 4 – 8
hours)
- F u r n a c e E ff i c i e n c y trials
Equipments
P e r f o r m a n c e e x p e r i m e n t s etc

Step6  Analysis of energy use  Energy and Material balance &

e n e rg y l o s s / w a s t e a na l ysi s

Step 7  Identification and  Ide nti fic a t ion & Consolidation

development of Energy E N C O N measures
Conservation (E NC ON)  Conceive, develop, a n d refine ideas
opportunities  R e v i e w t h e p r e v i o u s i d e a s s u g g e s t e d b y unit
personal
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by
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Step 8
 C o s t b e n e f i t a na l ysi s  Assess technical feasibility,
evicaobili
nom tyi c a n d prioriti z a tion of E N C O N
options for implementation
 S e l e c t t h e m o s t p r o m i s i n g proj e c t s
 Prioriti se b y l o w, m e d i u m , term
long measures

Step9  R e p o r t i n g & P r e s e n t a t i o n to D o c u m e n t a t i o n , R e p o r t P r e s e n t a t i o n t o t h e t op
t h e To p M a n a g e m e n t Management.
Step10 Phase III –Post Audit phase

 Implementation and Follow- Assist and Implement ENCON recommendation

up measures and Monitor the performance
 Action plan, Schedule for
implementation
 Follow-up and periodic review
Questions which an Energy Auditor should
ask
• What function does this system serve?
• How does this system serve its function?
• What is the energy consumption of this system?
• What are the indications that this system is
working properly ?
• If this system is not working, how can it be
restored to good working conditions/
• How can the energy cost of this system be
reduced?
 DETAILED ENERGY AUDIT
A TYPICAL INDUSTRIAL FORMAT OF REPORT
Energy Audit Team
Executive Summary –Scope & Purpose

Energy Audit Options & Recommendations

1. Introduction about the plant
2. General Plant details and descriptions
3. Component of production cost (Raw materials, energy, chemicals,
manpower, overhead, others)
4. Major Energy use and Areas
5. Production Process Description
6. Brief description of manufacturing process
7. Process flow diagram and Major Unit operations
8. Major Raw material Inputs, Quantity and Costs
9. Energy and Utility System Description
10. List of Utilities
11. Brief Description of each utility
1. Electricity
2. Steam
3. Water
4. Compressed air
5. Chilled water
6. Cooling water
4.0 Detailed Process flow diagram and Energy& Material balance
4.1 Flow chart showing flow rate, temperature, pressures of all
input-
Output streams
4Water balance for entire industry
1. Energy efficiency in utility and process systems
2. Specific Energy consumption
3. Boiler efficiency assessment
4. Thermic Fluid Heater performance assessments
5. Furnace efficiency Analysis
6. Cooling water system performance assessment
7. DG set performance assessment
8. Refrigeration system performance
9. Compressed air system performance
10. Electric motor load analysis
11. Lighting system
12. Energy Conservation Options & Recommendations
13. List of options in terms of no cost, low cost, medium cost and high
cost, annual energy savings and payback
2. Implementation plan for energy saving measures/Projects

ANNEXURE
Al. List of instruments
A2. List of Vendors and Other Technical details
Energy Audit Instruments
POWER ANALYSERS
Electrical Measuring Instruments:
These are instruments for measuring major
electrical parameters such as kVA, kW, PF,
Hertz, kvar, Amps and Volts. In addition
some of these instruments also measure
harmonics.

These instruments are applied on-line i.e on

running motors without any need to stop the
motor. Instant measurements can be taken
with hand-held meters, while more advanced
ones facilitates cumulative readings with print
outs at specified intervals.
FLUE GAS ANALYSERS
Combustion analyzer:
This instrument has in-built chemical cells
which measure various gases such as CO 2 ,
CO, NO X , SO X etc

Fuel Efficiency Monitor:

This measures Oxygen and temperature of
the flue gas. Calorific values of common
fuels are fed into the microprocessor which
calculates the combustion efficiency.

Fyrite:

A hand bellow pump draws the flue gas

sample into the solution inside the fyrite. A
chemical reaction changes the liquid
volume revealing the amount of gas.
Percentage Oxygen or CO 2 can be read
from the scale.
TEMPERATURE MEASURMENTS
Contact thermometer:

These are thermocouples which measures for

example flue gas, hot air, hot water temperatures by
insertion of probe into the stream.

For surface temperature a leaf type probe is used with

the same instrument.

Infrared Pyrometer:

This is a non-contact type measurement which when

directed at a heat source directly gives the
temperature read out. Can be useful for measuring hot
jobs in furnaces, surface temperatures etc.
FLOW MEASURMENTS – AIR ,WATER
Pitot Tube and manometer:

Air velocity in ducts can be

measured using a pitot tube and
inclined manometer for further
calculation of flows.

Ultrasonic flow meter:

This a non contact flow measuring

device using Doppler effect
principle. There is a transmitter and
receiver which are positioned on
opposite sides of the pipe. The
meter directly gives the flow. Water
and other fluid flows can be easily
measured with this meter.
 Speed Measurements:

In any audit exercise speed measurements

are critical as thay may change with
frequency, belt slip and loading.

A simple tachometer is a contact type

instrument which can be used where
direct access is possible.

More sophisticated and safer ones are

non contact instruments such as
Tachometer Stroboscope
stroboscopes.

Lux meters:

Illumination levels are measured with a

lux meter. It consists of a photo cell
which senses the light output,
converts to electrical impulses which
are calibrated as lux.
 Identification of Energy Conservation
Factors & Areas

Steps for conserving energy can be taken if we know

the correct factors and areas to be studied and also
details of fuels used.
These can be:
• Energy generation
• Energy distribution
• Energy usage by processes
• Fuel substitution
 Technical and Economic feasibility-
Factors
Technology availability, space, skilled manpower, reliability,
service,Impact of measure on safety, quality, production or
process.Maintenance requirements and spares availability
Sample Worksheet for Economic Feasibility
Name of Energy Efficiency Measure
i. Investment 2.Annual operating costs 3. Annual
savingsa. Equipments  Cost of  Thermal Energy
b. Civil works capital  Electrical
c. Instrumentati  Maintenance Energy
on  Manpower  Raw material
d. Auxiliaries  Energy  Waste disposal
 Depreciation
Net Savings /Year (Rs./year) Payback period in months
= (Annual savings-annual operating costs) = (Investment/net savings/year) x
12
 Energy Costs in Indian Scenario ?

Common Fuels
Power Costs
• Fuel oil,• Low Sulphur
In India Electricity costs
Heavy Stock (LSHS),• Light
Diesel Oil (LDO),• vary substantially not only
Liquefied Petroleum from State to State, but
Gas (LPG) also from city to city and
• Coal,• Lignite,• Wood also within consumer
to consumer – though
Fuels Cost Inputs & Factors power does the same
• Price at source, transport work everywhere.
charge, type of transport,
• Quality of fuel Reason:
• Tariff Structure
• Contaminations, Moisture,
Energy content (GCV)
Energy conservation
measures
 Understanding energy costs
An industrial energy bill summary

ENERGY BILL EXAMPLE

Type of energy Original units Unit Cost Monthly Bill (Rs)
Electricity 5,00,000 kWh Rs.4.00/kWh 20,00,000
Fuel oil 200,kL Rs.11,000 KL 22,00,000
Coal 1000 tons Rs.2,200/ton 22,00,000
Total 64,00,000

Conversion to common unit of energy

Electricity (1 kWh) = 860 kcal/kWh (0.0036 GJ)

Heavy fuel oil (calorific value, GCV) =10.000 kcal/litre ( 0.0411 GJ/litre)
Coal (calorific value, GCV) =4000 kcal/kg ( 28 GJ/ton)
 Benchmarking
• Benchmarking can be a useful tool for
understanding energy consumption patterns in the
industrial sector and also to take requisite
measures for improving energy efficiency.

• FACTORS INVOLVED:
– Scale of operation
– use of technology
– Raw material specifications and quality
– Product specifications and quality
 Benchmarking for Energy
Performance
• Internal Benchmarking
 Historical and trend analysis
• External Benchmarking
 Across similar industries
Scale of operation, use of technology, raw
material specification and quality and
product specification and quality
 Bench Marking Energy Performance

• Quantification of fixed and variable

energy consumption trends vis-à-vis production levels
• Comparison of the industry energy performance w.r.t.
various production levels (capacity utilization)
• Identification of best practices (based on the
external benchmarking data)
• Scope and margin availablefor energy
consumption and cost reduction
• Basis for monitoring and target setting exercises
 Benchmarking parameters
Production or Equipment Related

• Gross production related

e.g. kWh/MT clinker or cement produced (Cement

plant)
e.g. kWh/MT, kCal/kg, paper produced (Paper plant)

• Equipment / utility related

e.g. kWh/ton of refrigeration (on Air conditioning

plant)
e.g. kWh /litre in a diesel power generation plant.
 Measuring Energy Performance
Production Factor = Current year’s production
Reference year’s production

• Reference Year Equivalent Energy Use

• The reference year’s equivalent energy use (or reference year equivalent) is the
energy that would have been used to produce the current year’s production
output.
• The reference year equivalent is obtained by multiplying the reference year energy use by the
production factor (obtained above)
• Reference year equivalent = Reference year energy use x Production factor
• Plant Energy Performance is the improvement or deterioration from the reference
year. It is a measure of plant’s energy progress.

• Plant energy performance = Reference year equivalent – Current year’s energy x 100
Reference year equivalent
 Maximizing System
Efficiencies
- Some Measures
• Replace pumps, fans, air compressors, refrigeration
compressors, boilers, furnaces, heaters and
other energy conservation equipment, wherever
significant energy efficiency margins exist
• Eliminate steam leakages by trap improvements
• Maximize condensate recovery
• Adopt combustion controls for maximizing
combustion efficiency
 Matching Energy Usage to Requirement

• The mismatch between equipment capacity and user

requirement often leads to inefficiencies due to part
load operations, wastages etc. It is thus essential that
proper energy matching studies are carried out &
actions implemented.
Examples :
Eliminate throttling
Eliminate damper
operations
Fan resizing for better
efficiency.
Moderation of chilledwater temperature for
process chilling needs
 Optimising Energy Input
Requirement
🞂​ In order to ensure that the energy given to the system is
being put to optimal use, site specific measures
and
checks should be carried out regularly.

🞂​ EXAMPLES:

🞂​ Shuffling of compressors to match needs.

🞂​ Periodic review of insulation thickness

🞂​ Identify potential for heat networking and process

exchanger integration.
 Identification of energy
conservation opportunities
Fuel substitution
• Replacement of coal by coconut shells, rice husk etc
•Replacement of LDO by
LSHS Energy substitution
• Replacement of electric
heaters by steam heaters
• Replacement of steam based
hot water by solar systems
Energy Generation
• Captive power plant
• Steam generation
Energy usage by processes
• Analyze which process gets
high energy consumption
 Energy monitoring &
targeting
Importance
An effective monitoring & implementing system with
adequate technical ability for analyzing energy saving options
is key to ENERGY MANAGEMENT
Energy monitoring and targeting is primarily
a management technique that uses energy
information as a basis to eliminate waste,
reduce and control current level of energy use
and improve the existing operating

procedures .
These techniques covers all plant and building
utilities such as fuel, steam, refrigeration,
compressed air, water, effluent, and electricity
are managed as controllable resources in the
same way that raw materials, finished product
inventory, building occupancy, personnel and
capital are managed.----It Becomes the
“Energy Cost Centers.”
 Elements of Monitoring & Targeting System

• Recording -Measuring and recording energy

consumption
• • Analyzing Correlating energy consumption to a measured output, such as production
- quantity
• • Comparing -Comparing energy consumption to an appropriate standard benchmark

• • Setting Targets -Setting targets to reduce or control energy consumption

• • Monitoring - Comparing energy consumption to the set target on a regular basis

• • Reporting -Reporting the results including any variances from the targets which have been set

• • Controlling - Implementing management measures to correct any variances, which may have been
occurred.

• Particularly M&T system will involve the following:

• Checking the accuracy of energy invoices

• Allocating energy costs to specific departments (Energy Accounting Centres)

• Determining energy performance/efficiency

• Recording energy use, so that projects intended to improve energy efficiency can bechecked

* Highlighting performance problems in equipment or systems

 Data and Information Analysis
• Plant level information can be derived from financial accounting systems-utilities cost
centre
• Plant department level information can be found in comparative energy consumption
data for a group of similar facilities, service entrance meter readings etc.
• System level (for example, boiler plant) performance data can be determined
from sub metering data
• Equipment level information can be obtained from nameplate data, run-time and
schedule information, sub-metered data on specific energy consuming equipment
 Relating Energy Consumption and Production
• After collection of energy consumption, energy cost and production data, the next
stage of the monitoring process is to study and analyze the data and represent it for
day to day controls—so represent it graphically
Specific Energy
Consumption(SEC)
is energy
consumption per
unit of production
 CUSUM -Cumulative
Sum
• Cumulative Sum (CUSUM) represents the difference between the base line
and the actual consumption points over the base line period of time.
• This useful technique not only provides a trend line, it also
calculates savings/losses to date and shows when the performance
changes.
 CUSUM Technique
CUSUM analysis
1 Plot the Energy - Production graph for the first 9 months 4-Analysis-TABLE
2. Draw the best fit straight line
3. Derive the equation of the line, y=mx+c
4.Calculate the expected energy consumption based on
the equation
5.Calculate the difference between actual and
calculated energy use
6. Compute CUSUM
7. Plot the CUSUM graph
8.Estimate the savings accumulated from use of the heat
recovery system

1 Given
2 plot graph
3 fit equation
Case Study
The CUSUM Technique

Energy consumption and

production data were collected
for a plant over a period of 18
months.
During month 9, a heat
recovery system was installed.
Using the plant monthly data,
estimate
the savings made with the heat
recovery system. The plant
data is given in Table 8.3:

* toe = tonnes of oil equivalent.

Based on the graph 8.10
(see Table 8.4), savings of
44 toe
(50-6) have been
accumulated in the last
7 months. This
represents savings of
almost 2% of energy
consumption.
5-CUSUM -Analysis
The Sankey Diagram and its Use The Sankey diagram is very useful
tool to represent an entire input and output energy flow in any energy
equipment or system such as boiler, fired heaters, furnaces after
carrying out energy balance calculation. This diagram represents
visually various outputs and losses so that energy managers can focus
on finding improvements in a prioritized manner.

Example: The Figure 4.2

shows a Sankey diagram
for a reheating furnace.
From the Figure 4.2, it is
clear that exhaust flue gas
losses are a key area for
priority attention.
 Least Square Method
•We know, equation of
slope, Y=mx+c
Where,
“y” is dependent variable(i.e
energy consumption)
“x” is independent
variable(i.e production )
“c” is the value at which the
straight line curve intersect the
“y” axis.
“m” is the gradient of straight line
curve.

Therefore,
Energy consumed for the period=C+m*production for the
same period.
• Consider the sample
points, (X1,y1).(x2,y2)……
(xn,yn)
Therefore,
Equation of straight lines
are,
1.cn+m∑x=∑y
2.c∑x+m∑X2 = ∑xy….(on the
basis of production
i.e
independ
ent
variable)
n= no. of data points
These equations are known as normal
equations of the problems and they can be
used to
establish the value of “c” and “m”.
 Example

Answer
Case studies
 Energy Efficiency, a Step Towards Cleaner Production:
An Integrative Case Study of the Meat Processing
Industry in Hermosillo, Sonora
MUNGUIA, N.E. a*
, POOM, T. G. a, VELAQUEZ, L. a, ESQUER. J. a.

a
Universidad de Sonora, México

Blvd. Rosales y Luis Encinas, C.P. 83000. Hermosillo, Sonora, México.

*
Corresponding author, nmunguia@industrial.uson.mx

Abstract
The efficient use of resources within industrial systems is a key aspect to consider in order to achieve
sustainability, this perspective leads to the necessity to integrate production practices that incorporate economical,
ecological and social perspectives limiting the negative impact of industries toward the environment (Blenginin and
Shields, 2011). In matters of resource efficiency, energy to empower production processes is now a priority,
correspondingly, there is a relevance on the reduction of the use of energy and its negative impacts towards the
environment such as carbon emissions. Therefore the intersection of cleaner production and energy efficiency is
reinforced as a more integrative approach to achieve sustainability (UNEP, 2004). This work shows the results of
the application of energy efficiency audit with the objective to reduce the negative impacts to the environments
due the operation of a meat processing industry. In order to increase efficiency and upgrade its competitiveness.

Keywords: energy efficiency, cleaner production

1. Introduction
To convert raw materials to final products, production processes involve the usage of energy,
in quantities that can vary from production process to production process, resulting in
fluctuating negative impacts derived of the depletion of the energy resources (Jorgenson et
al, 2014). Therefore, since any production process involves usage of energy it is urgent to
think on its impact from the societal, economic and environmental perspectives, making it a
key element for the accomplishment of sustainable development (Stern, 2010).

Specifically, the food industry is one of the sectors with higher energy consumption
contributing 33% to the total, and is in the category of meat processing where it has the
greatest flow of energy used compared to other subcategories such as canned food, bottled
drinks, etc. (USDA, 2010).

“CLEANER PRODUCTION TOWARDS A SUSTAINABLE TRANSITION”

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2 5 t h International Workshop | Advances in Cleaner Production – Academic Work
Within the food industry energy use in the supply chain is undeniable, whether in activities
such as production, processing, packaging and distribution of food (USDA, 2010). In the case
of the food industry in particular the meat processing industry due to the need to maintain
low temperatures during the production process, storage temperatures, etc., results that this
is one of the industries more energy intensive (Tang, et al, 2013). This dependence on
energy consumption is the main cause of interest in the transition to a more energy-efficient
industry, this mainly derived from the relationship between energy use and food prices as
well as the environmental impacts of energy use as CO2 emissions to the environment (United
Nations Food and Agriculture FAO, 2014).

In order to exemplify the environmental implications of high energy consumption the metric
equivalent of carbon dioxide is used, which represents an amount of a greenhouse gas whose
atmospheric impact has been standardized to a unit mass of carbon dioxide based on the
global warming potential of the gas (EPA, 2012). In other words, based on their consumption
of electricity this metric describes how many emissions of greenhouse gases were released
for the operation of an activity (Dalkia, 2014). If we examine the energy used through this
equivalent of carbon metric we can recognize the ecological footprint of plants meat
processing which have these have a great impact on the environment and in this situation,
there is great potential opportunities for better use of energy in this type of facility (Sun and
Lee, 2006). The reason that energy efficiency plays an important role is that it not only
provides an increase in positive environmental performance of industry but also contributes
to cleaner production, increased competitiveness, increase in the innovation capacity and
allows companies to comply with government legislation (Schmidheiny, 1992).

2. Methods
A CP-EE methodology is described by UNEP (2004) and follows the systematic approach as
the CP methodologies. This work adapts the first three CP-EE methodology steps: Planning
and Organization, Pre-assessment and Assessment to compile information about the
processes and specifically theirs energy consumption. Aiming to contribute to a cleaner
production specifically towards the reduction to GHG emissions of the production processes
derived from the energy use. Also, for a more detailed energy audit some tools from
methodology described by AFNOR (2014) were taken into consideration to increase the
opportunities for the efficient usage of energy. Making and integrative and adapted approach
to energy efficiency in a meat processing plant. Due the nature of this work, the
implementation steps and validation of the energy management systems are omitted since
this work focus on the potential contribution for cleaner production through the reduction of
GHG emissions derived from the usage of electricity.

3. Results
Company A is a food-processing and distributing company located in Sonora, Mexico. The
system boundaries of this work are mainly focused on the food-processing and packing plant
process of this plant. For the purpose of this work the energy input that will be assessed is
electricity and its use on the main processes of production, cooling and lighting. The
distribution of the finished product is left out of the energy boundaries but could be
additionally researched as a new project, see Fig. 1.

“CLEANER PRODUCTION TOWARDS A SUSTAINABLE TRANSITION”

São Paulo – Brazil – May 20 t h to 22 n d - 2 0 1 5
3 5 t h International Workshop | Advances in Cleaner Production – Academic Work

Fig. 1. System boundaries.

In this case study energy consumption was translated into their carbon dioxide equivalent.
According to the glossary of climate change of the U.S Environmental Protection Agency this
metric compares the emission from various greenhouse gases based on their global warming
potential. Therefore the Carbon dioxide equivalent (CO2 E), expressed on Metric tons,
describes the potential climate warming capability of several gases on one standard unit. To
represent the global warming potential derived from the consumption/generation of electricity
standard ratios are used to convert in equivalents amounts of CO2.

This ratios are mostly defined by the electricity mix of each country, the Mexico’s electricity
mix, primarily entails the use of oil and gas, so the standard of conversion from KWh to their
carbon dioxide equivalents according to the 2014 Climate Registry Default Emission Factors
Mexico is defined with a 510.1 CO2 E by consumed MWh. In Fig 2, we can find the annual
description of the used energy sources at the company, and their detailed carbon equivalent
in metric tons.

“CLEANER PRODUCTION TOWARDS A SUSTAINABLE TRANSITION”

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4 5 t h International Workshop | Advances in Cleaner Production – Academic Work

Fig 2. CO2 Share 2012-2014

To obtain even more detailed information on the main energy consumers within the company
process a detailed energy balance was created. In this balance the company’s operation was
categorized into five categories that separate the energy consumers. Categories as
production, heating, ventilation and air conditioning (VAC), Information technology (IT) and
lighting, each category includes every appliance used to function and it is disaggregated in a
daily basis. Identification of equipment problems can also be determined with the
quantification of energy fluxes of the equipment, for this assessment of the consumption
hours by each equipment has been made and then translated to its CO2E.

Therefore, with this information a comprehensive approach to energy consumption and its
impacts toward the environment can be assessed and can point to the main areas in which
energy efficiency measures will have a major impact. To exemplify the categorization
processes realized in this work chart 1 describes the breakdown of consumption of the
appliances related to the production processes.

“CLEANER PRODUCTION TOWARDS A SUSTAINABLE TRANSITION”

São Paulo – Brazil – May 20 t h to 22 n d - 2 0 1 5
5 5 t h International Workshop | Advances in Cleaner Production – Academic Work

Chart 1. Quantification of energy usage on the production process.

Machine Operation daily hours Quantity Daily total consumption (KW) Cost CO2 E Share of total CO2 (%)

Machine 1 16 1 2.9 506.2 1.6 2

Machine 2 16 1 2.2 379.6 1.2 1

Machine 3 16 4 1 169.6 0.5 1

Machine 4 16 4 1.5 254.4 0.8 1

Machine 5 16 8 0.7 126.5 0.4 0

Machine 6 16 1 63 10687.9 34.6 34

Machine 7 16 1 1.1 186.6 0.6 1

Machine 8 16 1 0.8 147.5 0.4 0

Machine 9 16 2 8 1357.2 4.4 4

Machine 10 16 1 5.5 949.1 3.07 3

Machine 11 16 1 11 1866.1 6.05 6

Machine 12 16 1 0.7 127.2 0.4 0

Machine 13 16 1 1.8 316.3 1.02 1

Machine 14 16 1 1.1 189.8 0.6 1

Machine 15 16 1 2.6 442.9 1.4 1

Machine 16 16 1 1.4 253.1 0.8 1

Machine 17 16 1 5.5 949.1 3.07 3

Machine 18 16 1 2.2 379.6 1.2 1

Machine 19 16 1 2.2 379.6 1.2 1

Machine 20 16 2 0.4 67.8 0.2 0

Machine 21 16 1 1.5 254.4 0.8 1

Machine 22 16 1 2.2 379.6 1.2 1

Machine 23 16 1 9.4 1594.7 5.1 5

Machine 24 16 1 3.4 576.8 1.8 2

Machine 25 16 1 27 4580.5 14.8 15

Machine 26 16 1 0.7 127.2 0.4 0

Machine 27 16 1 8 1357.2 4.4 4

Machine 28 16 1 9 1526.8 4.9 5

Machine 29 16 1 1.4 240.4 0.7 1

Machine 30 16 1 2.2 379.6 1.2 1

Machine 31 16 1 4.1 695.5 2.2 2

Total 185.3 31450.46 101.9 100

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6 5 t h International Workshop | Advances in Cleaner Production – Academic Work

The evaluation of consumption and categorization of every appliance used will provide with
the information necessary to describe the daily KWh consumption per category and can later
be translated into its environmental indicator. In Fig 3, the daily KWh consumption of each
category is described in terms of environmental impacts of these categories expressed in CO2
Equivalents.

Fig 3. Energy usage environmental impact by categories

Energy efficiency potentials

The energy audit at the meat processing industry results with several measures that could be
implemented to improve energy efficiency and reduce both energy cost and pollution to the
environment: contributing to cleaner production of meat. The scope of the energy efficiency
measures aim to reduce the energy consumption of the main processes that use energy in
the production of meat. Measures include the installation of more energy efficient devices
through the systems and reducing the air leaks that could exist. Furthermore, is also advised
to prompt a reduction of energy use through the non-technical implementation but focusing
on the social aspect of energy consumption. I.e. it’s recommended to instruct employees with
basic notions for energy efficiency aimed to specific targets such as turning off of lighting
devices that are not being used.

With the identification of the main energy consumers a categorized list of the measures as
presented in Chart 2. Result of a full review of the literature on energy efficiency and a
selection of the viable options that can be implemented to achieve energy efficiency in the
specific context of this case study.

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7 5 t h International Workshop | Advances in Cleaner Production – Academic Work
Chart 2. Measures for energy efficiency
Scope Measures to improve the energy efficiency
- Installation of more energy-efficient lighting engineering
- Reduction of the wattage of lights
- Pale painted walls, ceilings and floors reflecting the light in a better way
- Matching of the illuminance on the purpose of the workplace
Illumination - Application of light sensors which adjust the illumination
(Hesselbach, 2012)
- Installation of motion detectors which are noticing if persons entering into
an area or room and the light gets switched on
- Intelligent time management and formation of zones depending on usage
- With a control system can every employee control the illumination from
his own computer
- Reduction of air leaks
- Decrease of the air pressure
Pneumatic Systems
- Converting into electric tools where possible
(Thollander and Palm, 2013)
- Usage of variable speed drive compressors
- Consideration of the possibility to use the compressor’s cooling output for
space heating purposes
- Usage of energy efficient motors (IEC standard 60034-2-1 or CEMEP
efficiency category)
- Regular maintenance of the drives
- Minimization of ration radii, accelerations, displaced mass and velocities
Electric drives - Regeneration of braking energy
(Müller et al., 2009)
- Utilization of variable speed drives (VSD)
- Preferential usage of direct drives to reduce the friction losses
- No oversizing of the electromagnetic drives
- Switching on or off in a targeted manner of the drives
- Selection of an energy efficient type of transmission
- Reduction of the flows through variable speed drives (VSD)
Pumping Systems
- Improvement of gears and transmission
(Thollander and Palm, 2013)
- Reduction of the flows through effective time control

Ventilation and Air-conditioning

Technology - Reduction of the air flows through variable speed drives (VSD)
(Thollander and Palm, 2013)
- Reduction of the flows through effective time control
- Heat recovering from hot exhaust air flows
- Usage of ceiling fans
- Shutdown of the heat circulation pumps in the summer
- Usage of air curtains for shuttle doors
Space heating and cooling - Reduction of the indoor temperature during heating season
systems - Improvement of the roof and wall insulation
(Thollander and Palm, 2013) - Supply of heat and cooling at the right temperature
- Better insulation of pipes, heat exchangers etc.
- If possible converting from steam into waterborne systems
- Usage of heat pumps
- Taking advantage of free cooling
Hot tap water systems (Thollander - Usage of more efficient shower heads and fittings
and Palm, 2013) - Better insulation of pipes, heat exchangers, etc.
- Converting from diesel and gasoline vehicles into more energy-efficient
ones (e.g., electrically powered)
- Maintenance of adequate tire pressure
Internal Transport
(Thollander and Palm, 2013) - Improvement of the production planning to reduce transport distance
- Optimization of the storage location to reduce the transport distance

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8 5 t h International Workshop | Advances in Cleaner Production – Academic Work
4. Conclusions

Industrial processes need energy to function, implying several negative impacts to the
environment. Therefore is imperative to improve the efficiency of such processes in order to
achieve cleaner production and move to sustainable production. It is noted that the company
in which this case study was developed has a remarking interest in minimize the damage that
their processes have on the environment. As a summary, the main opportunities in this
company can be described:

 Company A complies with all the regulatory framework of the meat processing
industry, having an innocuous production processes.
 The implementation of some of the previously mentioned measures for energy efficient
will have an impact on the overall efficiency of the studied company without
affecting the regulatory compliance.
 Opportunities to further research on cleaner sources for energy should be noted and
are also part of the company’s transition to cleaner energy.
 Energy efficiency is one of the main topics that should be addressed in matters of
cleaner production.
 The result of this first three steps on the CP-EE methodology serve as the basis to
more energy efficient and cleaner production processes in Company A.
Therefore a
more depth analysis of materials flow is recommended.

5. References
UNEP, 2004. Guidelines for the Integration of Cleaner Production and Energy EfficiencyUnited Nations
Environment Programme.
Blengini, G.A. y Shields, D.J., 2010. Green labels and sustainability reporting Overview of the building
products supply chain in Italy. Management of Environmental Quality: An International Journal, 16(4),
21(4), pp.477-493.
Jorgenson, A.K., Alekseyko, k., Giedraitis, V. 2014. “Energy consumption, human well-being and
economic development in central and eastern European nations: A cautionary tale of sustainability”,
Energy Policy, 66, pp. 419-427.
Stern, D. I. 2011. The role of energy in economic growth. Annals of the New York Academy of
Sciences, 1219: 26–51. doi: 10.1111/j.1749-6632.2010.05921.x
Tang, P. & Mike Jones. 2013. ENERGY CONSUMPTION GUIDE FOR SMALL TO MEDIUM RED MEAT
PROCCESSING FACILITIES. Australian Meat Processor Corporation LTD
Dalkia. 2014. Guide equivalences CO2 [ONLINE] Disponible en: http://www.dalkia.ie/ireland-
energy/ressources/documents/1/20202,Guide-equivalences-CO2.pdf.
Sun, H & Lee, S. 2006. Case study of data centers’ energy performance. Energy and Buildings, 38(5),
pp.522–533. Disponible en: http://linkinghub.elsevier.com/retrieve/pii/S0378778805001738
Schmidheiny, S. with the Business Council on Sustainable Development. 1992. “Changing course: a
global business perspective on development and the environment”, ISBN: 978-0-262-69153-6,MIT
Press.
FAOSTAT, 2013, “FAO Statistical Yearbook 2013: World Food and Agriculture”, ISSN: 2225-7373, Food
and Agriculture Organization of the United Nations, Rome, Italy.
Afnor Group. 2014. Guideline to efficient Energy management systems according to ISO 50001.
[ONLINE] Disponible en: http://www.gut-cert.de/guide-enms.html

“CLEANER PRODUCTION TOWARDS A SUSTAINABLE TRANSITION”

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 12. APPLICATION OF NON-CONVENTIONAL &
RENEWABLE ENERGY SOURCES
1. Concept of Renewable Energy

Renewable energy sources also called non-conventional energy, are sources that are continuously
replenished by natural processes. For example, solar energy, wind energy, bio-energy - bio-fuels grown
sustain ably), hydropower etc., are some of the examples of renewable energy sources

A renewable energy system converts the energy found in sunlight, wind, falling-water, sea-waves,
geothermal heat, or biomass into a form, we can use such as heat or electricity. Most of the renewable
energy comes either directly or indirectly from sun and wind and can never be exhausted, and therefore
they are called renewable.

However, most of the world's energy sources are derived from conventional sources-fossil fuels such as
coal, oil, and natural gases. These fuels are often termed non-renewable energy sources. Although, the
available quantity of these fuels are extremely large, they are nevertheless finite and so will in principle
‘run out’ at some time in the future

Renewable energy sources are essentially flows of energy, whereas the fossil and nuclear fuels are, in
essence, stocks of energy

Various forms of renewable energy

Solar energy

Wind energy

Bio energy

Hydro energy

Geothermal energy

Wave and tidal energy

This chapter focuses on application potential of commercially viable renewable energy sources such as
solar, wind, bio and hydro energy in India.

2. Solar Energy

Solar energy is the most readily available and free source of

energy since prehistoric times. It is estimated that solar
energy equivalent to over 15,000 times the world's annual
commercial energy consumption reaches the earth every
year.

India receives solar energy in the region of 5 to 7 kWh/m2 for 300 to 330 days in a year. This energy is
sufficient to set up 20 MW solar power plant per square kilometre land area.
Solar energy can be utilised through two different routes, as solar thermal route and solar electric (solar
photovoltaic) routes. Solar thermal route uses the sun's heat to produce hot water or air, cook food,
drying materials etc. Solar photovoltaic uses sun’s heat to produce electricity for lighting home and
building, running motors, pumps, electric appliances, and lighting.

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Solar Thermal Energy Application

In solar thermal route, solar energy can be converted into thermal energy with the help of solar
collectors and receivers known as solar thermal devices.
The Solar-Thermal devices can be classified into three categories:

Low-Grade Heating Devices - up to the temperature of 100C.

Medium-Grade Heating Devices -up to the temperature of 100-300C
High-Grade Heating Devices -above temperature of 300C

Low-grade solar thermal devices are used in solar water heaters, air-heaters, solar cookers and solar
dryers for domestic and industrial applications.

Solar water heaters

Most solar water heating systems have two main parts: a

solar collector and a storage tank. The most common
collector is called a flat-plate collector (see Figure 12.1).
It consists of a thin, flat, rectangular box with a
transparent cover that faces the sun, mounted on the roof
of building or home. Small tubes run through the box and
carry the fluid – either water or other fluid, such as an
antifreeze solution – to be heated. The tubes are attached
to an absorber plate, which is painted with special
coatings to absorb the heat. The heat builds up in the
collector, which is passed to the fluid passing through the
tubes.
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An insulated storage tank holds the hot water. It is
similar to water heater, but larger is size. In case of systems that use fluids, heat is passed from hot
fluid to the water stored in the tank through a coil of tubes.
 12. Application of Non-Conventional & Renewable Energy Sources

Box type solar cookers: The box type solar cookers with a single reflecting mirror are
the most popular in India. These cookers have
proved immensely popular in rural areas where
women spend considerable time for collecting
firewood. A family size solar cooker is sufficient
for 4 to 5 members and saves about 3 to 4 cylinders
of LPG every year. The life of this cooker is upto
15 years. This cooker costs around Rs.1000 after
allowing for subsidy. Solar cookers.(Figure 12.2)
Figure 12.2 Box Type Solar are widely available in the market.

Parabolic concentrating solar cooker:

A parabolic solar concentrator comprises of sturdy
Fibre Reinforced Plastic (FRP) shell lined with
Stainless Steel (SS) reflector foil or aluminised
polyester film. It can accommodate a cooking
vessel at its focal point. This cooker is designed to
direct the solar heat to a secondary reflector inside
the kitchen, which focuses the heat to the bottom of
a cooking pot. It is also possible to actually fry,
bake and roast food. This system generates 500 kg
of steam, which is enough to cook two meals for
500 people (see Figure 12.3). This cooker costs
upward of Rs.50,000.

Positioning of solar panels or collectors can

greatly influence the system output, efficiency and
payback. Tilting mechanisms provided to the
Figure 12.3 Parabolic Collector
collectors need to be adjusted according to
seasons (summer and winter) to maximise the collector efficiency.

The period four to five hours in late morning and early afternoon (between 9 am to
3pm) is commonly called the "Solar Window". During this time, 80% of the total
collectable energy for the day falls on a solar collector. Therefore, the collector should
be free from shade during this solar window throughout the year - Shading, may arise
from buildings or trees to the south of the location.

Solar Electricity Generation

Solar Photovoltaic (PV): Photovoltaic is the

technical term for solar electric. Photo
means "light" and voltaic means "electric".
PV cells are usually made of silicon, an
element that naturally releases electrons
when exposed to light. Amount of electrons
released from silicon cells depend upon
intensity of light incident on it. The silicon
cell is covered with a grid of metal that
directs the electrons to flow in a path to
create an electric current. This current is

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Figure 12.4 Solar Photovoltaic Array
 12. Application of Non-Conventional & Renewable Energy Sources

guided into a wire that is connected to a battery or DC appliance. Typically, one cell
produces about 1.5 watts of power. Individual cells are connected together to form a
solar panel or module, capable of producing 3 to 110 Watts power. Panels can be
connected together in series and parallel to make a solar array (see Figure 12.4),
which can produce any amount of Wattage as space will allow. Modules are usually
designed to supply electricity at 12 Volts. PV modules are rated by their peak Watt
output at solar noon on a clear day.

Some applications
for PV systems
are lighting for
commercial
buildings, outdoor
(street)
lighting (see
Figure 12.5), rural
and village
lighting etc. Solar Figure 12.5 Photovoltaic Domestic and Streetlights
electric power
systems can offer
independence from the utility grid and offer protection during extended power
failures. Solar PV systems are found to be economical especially in the hilly and far
flung areas where conventional grid power supply will be expensive to reach.

PV tracking systems is an alternative to the fixed, stationary PV panels. PV tracking

systems are mounted and provided with tracking mechanisms to follow the sun as it
moves through the sky. These tracking systems run entirely on their own power and
can increase output by 40%.

Back-up systems are necessary since PV systems only generate electricity when the
sun is shining. The two most common methods of backing up solar electric systems
are connecting the system to the utility grid or storing excess electricity in batteries
for use at night or on cloudy days.

Performance
The performance of a solar cell is measured in terms of its efficiency at converting
sunlight into electricity. Only sunlight of certain energy will work efficiently to create
electricity, and much of it is reflected or absorbed by the material that make up the
cell. Because of this, a typical commercial solar cell has an efficiency of 15%—only
about one-sixth of the sunlight striking the cell generates electricity. Low efficiencies
mean that larger arrays are needed, and higher investment costs. It should be noted
that the first solar cells, built in the 1950s, had efficiencies of less than 4%.

Solar Water Pumps

In solar water pumping system, the pump is driven by motor run by solar electricity
instead of conventional electricity drawn from utility grid. A SPV water pumping
system consists of a photovoltaic array mounted on a stand and a motor-pump set
compatible with the photovoltaic array. It converts the solar energy into electricity,
which is used for running the motor pump set. The pumping system draws water from
the open well, bore well, stream, pond, canal etc

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 12. Application of Non-Conventional & Renewable Energy Sources

Case Example:
Under the Solar
Photovolatic Water
Pumping Programme
of the Ministry of
Non-conventional
Energy Sources
during 2000-01
Punjab
Development
the Agency
(PEDA) E
has
nergy
completed installation
of 500 solar pumps in
Punjab for
agricultural uses.
Under this project, Figure 12.6 Photovoltaic Water Pumping
1800 watt PV array was coupled with a 2 HP DC motor pump set. The system is
capable of delivering about 140,000 litres water every day from a depth of about 6 – 7
metres. This quantity of water is considered adequate for irrigating about 5 –8 acres
land holding for most of the crops. Refer Figure 12.6.

12.3 Wind Energy

Wind energy is basically harnessing of wind power to
produce electricity. The kinetic energy of the wind is
converted to electrical energy. When solar radiation
enters the earth’s atmosphere, different regions of the
atmosphere are heated to different degrees because of
earth curvature. This heating is higher at the equator
and lowest at the poles. Since air tends to flow from
warmer to cooler regions, this causes what we call
winds, and it is these airflows that are harnessed in
windmills and wind turbines to produce power.

Wind power is not a new development as this power,

in the form of traditional windmills -for grinding
corn, pumping water, sailing ships – have been used
for centuries. Now wind power is harnessed to
generate electricity in a larger scale with better
technology.

Wind Energy Technology

The basic wind energy conversion device is the wind turbine. Although various
designs and configurations exist, these turbines are generally grouped into two types:

1. Vertical-axis wind turbines, in which the axis of rotation is vertical with

respect to the ground (and roughly perpendicular to the wind stream),
2. Horizontal-axis turbines, in which the axis of rotation is horizontal with
respect to the ground (and roughly parallel to the wind stream.)

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 12. Application of Non-Conventional & Renewable Energy Sources

Figure 12.7 Wind Turbine Configuration

The Figure 12.7 illustrates the two types of turbines and typical subsystems for an electricity generation
application. The subsystems include a blade or rotor, which converts the energy in the wind to
rotational shaft energy; a drive train, usually including a gearbox and a generator, a tower that supports
the rotor and drive train, and other equipment, including controls, electrical cables, ground support
equipment, and interconnection equipment.

Wind electric generators (WEG)

Wind electric generator converts kinetic energy available in wind to electrical energy by using rotor,
gear box and generator. There are a large number of manufacturers for wind electric generators in India
who have foreign collaboration with different manufacturers of Denmark, Germany, Netherlands,
Belgium, USA, Austria, Sweden, Spain, and U.K. etc. At present, WEGs of rating ranging from 225
kW to 1000 kW are being installed in our country.

Evaluating Wind Mill Performance

Wind turbines are rated at a certain wind speed and annual energy output

Annual Energy Output = Power x Time

Example: For a 100 kW turbine producing 20 kW at an average wind speed of 25 km/h, the calculation
would be:

100 kW x 0.20 (CF) = 20 kW x 8760 hours = 175,200 kWh

The Capacity Factor (CF) is simply the wind turbine's actual energy output for the year divided by the
energy output if the machine operated at its rated power output for the entire year. A reasonable
capacity factor would be 0.25 to 0.30 and a very good capacity factor would be around 0.40. It is
important to select a site with good capacity factor, as economic viability of wind power projects is
extremely sensitive to the capacity factor.

Wind Potential
In order for a wind energy system to be feasible there must be an adequate wind supply. A wind energy
system usually requires an average annual wind speed of at least 15 km/h. The following table
represents a guideline of different wind speeds and their potential in producing electricity.

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 12. Application of Non-Conventional & Renewable Energy Sources

Average Wind Speed Suitability

km/h (mph)
Up to 15 (9.5) No good
18 (11.25) Poor
22 (13.75) Moderate
25 (15.5) Good
29 (18) Excellent

A wind generator will produce lesser power in summer than in winter at the same
wind speed as air has lower density in summer than in winter.

Similarly, a wind generator will produce lesser power in higher altitudes - as air
pressure as well as density is lower -than at lower altitudes.

The wind speed is the most important factor influencing the amount of energy a wind
turbine can produce. Increasing wind velocity increases the amount of air passing the
rotor, which increases the output of the wind system.

In order for a wind system to be effective, a relatively consistent wind flow is

required. Obstructions such as trees or hills can interfere with the wind supply to the
rotors. To avoid this, rotors are placed on top of towers to take advantage of the strong
winds available high above the ground. The towers are generally placed 100 metres
away from the nearest obstacle. The middle of the rotor is placed 10 metres above any
obstacle that is within 100 metres.

Wind Energy in India

India has been rated as one of the most promising countries for wind power
development, with an estimated potential of 20,000 MW. Total installed capacity of
wind electric generators in the world as on Sept. 2001 is 23270 MW. Germany 8100
MW, Spain- 3175 MW, USA 4240 MW, Denmark 2417 MW, and India - 1426 MW
top the list of countries. Thus, India ranks fifth in the world in Wind power
generation.

There are 39 wind potential stations in Tamil Nadu, 36 in Gujarat, 30 in Andhra

Pradesh, 27 in Maharashtra, 26 in Karnataka, 16 in Kerala, 8 in Lakshadweep, 8
Rajasthan, 7 in Madhya Pradesh, 7 in Orissa, 2 in West Bengal, 1 in Andaman
Nicobar and 1 in Uttar Pradesh. Out of 208 suitable stations 7 stations have shown
wind power density more than 500 Watts/ m2.

Central Govt. Assistance and Incentives

The following financial and technical assistance are provided to promote, support and
accelerate the development of wind energy in India:
Five years tax holiday
100% depreciation in the first year
Facilities by SEB's for grid connection
Energy banking and wheeling and energy buy back
Industry status and capital subsidy
Electricity tax exemption
Sales tax exemption

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 12. Application of Non-Conventional & Renewable Energy Sources

Applications
 Utility interconnected wind turbines generate power which is synchronous
with the grid and are used to reduce utility bills by displacing the utility power
used in the household and by selling the excess power back to the electric
company.
 Wind turbines for remote homes (off the grid) generate DC current for battery
charging.
 Wind turbines for remote water pumping generate 3 phase AC current suitable
for driving an electrical submersible pump directly. Wind turbines suitable for
residential or village scale wind power range from 500 Watts to 50 kilowatts.

12.4 Bio Energy

Biomass is a renewable energy resource derived from the
carbonaceous waste of various human and natural
activities. It is derived from numerous sources, including
the by-products from the wood industry, agricultural
crops, raw material from the forest, household wastes etc.

Biomass does not add carbon dioxide to the atmosphere as it absorbs the same amount
of carbon in growing as it releases when consumed as a fuel. Its advantage is that it
can be used to generate electricity with the same equipment that is now being used for
burning fossil fuels. Biomass is an important source of energy and the most important
fuel worldwide after coal, oil and natural gas. Bio-energy, in the form of biogas,
which is derived from biomass, is expected to become one of the key energy
resources for global sustainable development. Biomass offers higher energy efficiency
through form of Biogas than by direct burning (see chart below).

Application

Bio energy is being used for:

Cooking, mechanical applications,
pumping, power generation
Some of the devices : Biogas
plant/ gasifier/burner, gasifier
engine pump sets, stirling engine
pump sets, producer gas/ biogas
based engine generator sets

Biogas Plants

Biogas is a clean and efficient fuel, generated from cow-dung, human

waste or any kind of biological materials derived through anaerobic
fermentation process. The biogas consists of 60% methane with rest
mainly carbon-di-oxide. Biogas is a safe fuel for cooking and
lighting. By-product is usable as high-grade manure.

A typical biogas plant has the following components: A digester in

which the slurry (dung mixed with water) is fermented, an inlet tank - for mixing the feed and letting it
into the digester, gas holder/dome in which the generated gas is collected, outlet tank to remove the

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 12. Application of Non-Conventional & Renewable Energy Sources

spent slurry, distribution pipeline(s) to transport the gas into the kitchen, and a manure pit, where the
spent slurry is stored.

Biomass fuels account for about one-third of the total fuel used in the country. It is the most important
fuel used in over 90% of the rural households and about 15% of the urban households. Using only local
resources, namely cattle waste and other organic wastes, energy and manure are derived. Thus the
biogas plants are the cheap sources of energy in rural areas. The types of biogas plant designs popular
are: floating drum type, fixed dome-type and bag-type portable digester.

Biomass Briquetting

The process of densifying loose agro-waste into a

solidified biomass of high density, which can be
conveniently used as a fuel, is called Biomass
Briquetting (see Figure 12.8). Briquette is also
termed as "Bio-coal". It is pollution free and eco-
friendly. Some of the agricultural and forestry
residues can be briquetted after suitable pre-
treatment. A list of commonly used biomass
materials that can be briquetted are given below:

CornCob, JuteStick, Sawdust, PineNeedle,

Bagasse, CoffeeSpent, Tamarind, CoffeeHusk,
AlmondShell, Groundnutshells, CoirPith, Figure 12.8 Biomass Briquetting
BagaseePith, Barleystraw, Tobaccodust,
RiceHusk, Deoiled Bran

Advantages

Some of advantages of biomass briquetting are high calorific value with low ash content, absence of
polluting gases like sulphur, phosphorus fumes and fly ash- which eliminate the need for pollution
control equipment, complete combustion, ease of handling, transportation & storage - because of
uniform size and convenient lengths.

Application

Biomass briquettes can replace almost all conventional fuels like coal, firewood and lignite in almost
all general applications like heating, steam generation etc. It can be used directly as fuel instead of coal
in the traditional chulhas and furnaces or in the gasifier. Gasifier converts solid fuel into a more
convenient-to-use gaseous form of fuel called producer gas.

Biomass Gasifiers

Biomass gasifiers (see Figure 12.9) convert the

solid biomass (basically wood waste, agricultural
residues etc.) into a combustible gas mixture
normally called as producer gas. The conversion
efficiency of the gasification process is in the range
of 60%–70%. The producer gas consists of mainly
carbon-monoxide, hydrogen, nitrogen gas and
methane, and has a lower calorific value (1000–
1200 kcal/Nm3).

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Gasification of biomass and using it in place of conventional direct burning devices will
result in savings of atleast 50% in fuel consumption. The gas has been found
suitable for combustion in the internal combustion engines for the production of power.

Applications:

Water pumping and Electricity generation: Using biomass gas, it possible to operate a
diesel engine on dual fuel mode-part diesel and part biomass gas. Diesel substitution of
the order of 75 to 80% can be obtained at nominal loads. The mechanical energy thus derived
can be used either for energizing a water pump set for irrigational purpose or for coupling
with an alternator for electrical power generation - 3.5 KW - 10 MW

Heat generation: A few of the devices, to which gasifier could be retrofitted, are dryers-
for drying tea, flower, spices, kilns for baking tiles or potteries, furnaces for melting non-
ferrous metals, boilers for process steam, etc.

Direct combustion of biomass has been recognized as an important route for generation
of power by utilization of vast amounts of agricultural residues, agro-industrial residues
and forest wastes. Gasifiers can be used for power generation and available up to a capacity
500 kW. The Government of India through MNES and IREDA is implementing power-
generating system based on biomass combustion as well as biomass gasification

High Efficiency Wood Burning Stoves

These stoves save more than 50% fuel wood consumption. They reduce drudgery of women
saving time in cooking and fuel collection and consequent health hazards. They also help
in saving firewood leading to conservation of forests. They also create
employment opportunities for people in the rural areas.

Bio fuels

Unlike other renewable energy sources, biomass can be

converted directly into liquid fuels— biofuels— for
our transportation needs (cars, trucks, buses, airplanes, and
trains). The two most common types of biofuels are
ethanol and biodiesel. See Figure 12.10.

Ethanol is an alcohol, similar to that used in beer and wine. It

is made by fermenting any biomass high in
carbohydrates (starches, sugars, or celluloses) through a
process similar to brewing beer. Ethanol is mostly used as a Figure 12.10 Biodiesel
fuel additive to cut down a vehicle's carbon monoxide and Driven Bus
other smog-causing
emissions. Flexible-fuel vehicles, which run on mixtures of gasoline and up to 85%
ethanol, are now available.

Biodiesel, produced by plants such as rapeseed (canola), sunflowers and soybeans, can be
extracted and refined into fuel, which can be burned in diesel engines and buses. Biodiesel
can also made by combining alcohol with vegetable oil, or recycled cooking greases. It can
be used as an additive to reduce vehicle emissions (typically 20%) or in its pure form
as a renewable alternative fuel for diesel engines.

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 12. Application of Non-Conventional & Renewable Energy Sources

Biopower

Biopower, or biomass power, is the use of biomass to generate electricity. There are six major
types of biopower systems: direct-fired, cofiring, gasification, anaerobic digestion, pyrolysis,
and small - modular.

Most of the biopower plants in the world use direct-fired systems. They burn bioenergy
feedstocks directly in boiler to produce steam. This steam drives the turbo-generator. In
some industries, the steam is also used in manufacturing processes or to heat buildings.
These are known as combined heat and power facilities. For example, wood waste is
often used to produce both electricity and steam at paper mills.

Many coal-fired power plants use cofiring systems to significantly reduce

emissions, especially sulfur dioxide emissions. Cofiring involves using bio energy
feedstock as a supplementary fuel source in high efficiency boilers.

Gasification systems use high temperatures and an oxygen-starved environment to

convert biomass into a gas (a mixture of hydrogen, carbon monoxide, and methane). The
gas fuels a gas turbine, which runs an electric generator for producing power.

The decay of biomass produces methane gas, which can be used as an energy source.
Methane can be produced from biomass through a process called anaerobic digestion.
Anaerobic digestion involves using bacteria to decompose organic matter in the absence
of oxygen. In landfills –scientific waste disposal site - wells can be drilled to release the
methane from the decaying organic matter. The pipes from each well carry the gas to a
central point where it is filtered and cleaned before burning. Methane can be used as an
energy source in many ways. Most facilities burn it in a boiler to produce steam for
electricity generation or for industrial processes. Two new ways include the use of
microturbines and fuel cells. Microturbines have outputs of 25 to 500 kilowatts. About
the size of a refrigerator, they can be used where there are space limitations for power
production. Methane can also be used as the "fuel" in a fuel cell. Fuel cells work much
like batteries, but never need recharging, producing electricity as long as there is fuel.

In addition to gas, liquid fuels can be produced from biomass through a process
called pyrolysis. Pyrolysis occurs when biomass is heated in the absence of oxygen. The
biomass then turns into liquid called pyrolysis oil, which can be burned like petroleum to
generate electricity. A biopower system that uses pyrolysis oil is being commercialized.

Several biopower technologies can be used in small, modular systems. A small,

modular system generates electricity at a capacity of 5 megawatts or less. This system is
designed for use at the small town level or even at the consumer level. For example, some
farmers use the waste from their livestock to provide their farms with electricity. Not only
do these systems provide renewable energy, they also help farmers meet environmental
regulations.

Biomass Cogeneration

Cogeneration improves viability and profitability of sugar industries. Indian sugar mills
are rapidly turning to bagasse, the leftover of cane after it is crushed and its juice
extracted, to generate electricity. This is mainly being done to clean up the environment, cut
down power costs and earn additional revenue. According to current estimates, about 3500
MW of power can be generated from bagasse in the existing 430 sugar mills in the
country. Around 270 MW of power has already been commissioned and more is under
construction.

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 12. Application of Non-Conventional & Renewable Energy Sources

12.5 Hydro Energy

The potential energy of

falling water, captured
and converted to
mechanical energy
waterwheels, powered
by the
start of the industrial
revolution.
Wherever sufficient head,
or change in elevation,
could be found, rivers
and streams were
dammed and mills were
built. Water under
pressure flows through a Figure 12.11 Hydro Power Plant
turbine causing it to spin.
The Turbine is connected to a generator, which produces electricity (see Figure
12.11). In order to produce enough electricity, a hydroelectric system requires a
location with the following features:
Change in elevation or head: 20 feet @ 100 gal/min = 200 Watts.
100 feet head @ 20 gal/min gives the same output.

In India the potential of small hydro power is estimated about 10,000 MW. A total of
183.45 MW small Hydro project have been installed in India by the end of March
1999. Small Hydro Power projects of 3 MW capacity have been also installed
individually and 148 MW project is under construction.

Small Hydro

Small Hydro Power is a reliable, mature and proven

technology. It is non-polluting, and does not involve
setting up of large dams or problems of deforestation,
submergence and rehabilitation. India has an estimated
potential of 10,000 MW

Micro Hydel
Hilly regions of India, particularly the Himalayan belts, are
endowed with rich hydel resources with tremendous potential.
The MNES has launched a promotional scheme for portable
micro hydel sets for these areas. These sets are small, compact
and light weight. They have almost zero maintenance cost and
can provide electricity/power to small cluster of villages. They are
ideal substitutes for diesel sets run in those areas at high
generation cost.

Micro (upto 100kW) mini hydro (101-1000 kW) schemes can provide power for
farms, hotels, schools and rural communities, and help create local industry.

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 12. Application of Non-Conventional & Renewable Energy Sources

12.6 Tidal and Ocean Energy

Tidal Energy

Tidal electricity generation involves the construction

of a barrage across an estuary to block the incoming
and outgoing tide. The head of water is then used to
drive turbines to generate electricity from the
elevated water in the basin as in hydroelectric dams.

Barrages can be designed to generate electricity on the

ebb side, or flood side, or both. Tidal range may vary
over a wide range (4.5-12.4 m) from site to site. A
tidal range of at least 7 m is required for economical
operation and for sufficient head of water for the
turbines.

Ocean Energy

Oceans cover more than 70% of Earth’s surface, making them the world’s largest
solar collectors. Ocean energy draws on the energy of ocean waves, tides, or on the
thermal energy (heat) stored in the ocean. The sun warms the surface water a lot more
than the deep ocean water, and this temperature difference stores thermal energy.

The ocean contains two types of energy: thermal energy from the sun’s heat, and
mechanical energy from the tides and waves.

Ocean thermal energy is used for many applications, including electricity generation.
There are three types of electricity conversion systems: closed-cycle, open cycle, and
hybrid. Closed cycle systems use the ocean’s warm surface water to vaporize a
working fluid, which has a low boiling point, such as ammonia. The vapour expands
and turns a turbine. The turbine then activates a generator to produce electricity.
Open-cycle systems actually boil the seawater by operating at low pressures. This
produces steam that passes through a turbine / generator. The hybrid systems combine
both closed-cycle and open-cycle systems.

Ocean mechanical energy is quite different from ocean thermal energy. Even though
the sun affects all ocean activity, tides are driven primarily by the gravitational pull of
the moon, and waves are driven primarily by the winds. A barrage (dam) is typically
used to convert tidal energy into electricity by forcing the water through turbines,
activating a generator.

India has the World's largest programmes for renewable energy. Several renewable
energy technologies have been developed and deployed in villages and cities of India.
A Ministry of Non-Conventional Energy Sources (MNES) created in 1992 for all
matters relating to Non-Conventional / Renewable Energy. Government of India also
created Renewable Energy Development Agency Limited (IREDA) to assist and

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 12. Application of Non-Conventional & Renewable Energy Sources

provide financial assistance in the form of subsidy and low interest loan for renewable
energy projects.

IREDA covers a wide spectrum of financing activities including those that are
connected to energy conservation and energy efficiency. At present, IREDA's lending
is mainly in the following areas: -
 Solar energy technologies, utilization of solar thermal and solar photo voltaic
systems
 Wind energy setting up grid connected Wind farm projects
 Small hydro setting up small, mini and micro hydel projects
 Bio-energy technologies, biomass based co-generation projects, biomass
gasification, energy from waste and briquetting projects
 Hybrid systems
 Energy efficiency and conservation

The estimated potential of various Renewable Energy technologies in India by

IREDA are given below.

Energy source estimated potential

Solar Energy 20 MW / sq. km

Wind Energy 20,000 MW
Small Hydro 10,000 MW
Ocean Thermal Power 50,000 MW
Sea Wave Power 20,000 MW
Tidal Power 10,000 MW
Bio energy 17,000 MW
Draught Animal Power 30,000 MW
Energy from MSW 1,000 MW
Biogas Plants 12 Million
Improved Wood Burning Stoves Plants
Bagasse-based cogeneration 120 Million
Stoves
3500energy
Cumulative achievements in renewable MW sector (As on 31.03.2000)

Sources / Technologies Unit Upto31.03.2000

Wind Power MW 1167
Small Hydro MW 217
Biomass Power & Co-generation MW 222
Solar PV Power MW / Sq. km 42
Urban & MSW MW 15.21
Solar Heater m2. Area 480000
Solar Cookers No. 481112
Biogas Plants Nos. in Million 2.95
Biomas Gasifier MW 34
Improved Nos. in Million 31.9
Chulhas

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 12. Application of Non-Conventional & Renewable Energy Sources

QUESTIONS

1 What do you mean by renewable energy

2 Why is solar energy potential high in India?
3. Explain working of solar water heater?
4. List few applications of low temperature water heaters in domestic and
industrial use
5. What are the two methods by which energy can be recovered from solar
radiation
6. How can the performance of solar collectors be improved?
7. Explain any two applications of concentrated solar energy?
8. What do you mean by photovoltaic?
9. Explain the terms cell, module and array as applicable to photovoltaic.
10. What are the typical applications of photovoltaic power?
11. Name the few states with high wind energy potential in India.
12.. What are the criteria for selection of wind mill installation?
13. What ere the incentives available for wind mill installation?
14. Explain the bio-energy potential in India and its applications.
15. What are the various methods by which power can be generated from
biomass?
16. What is the role of IREDA in renewable energy sector
17. India has recorded good growth in wind energy sector. Do you agree? What
are the factors responsible for such a high growth?

REFERENCES

1. Alternate Energy Sources by T H Taylor.Adam Hilger Ltd, Bristol

2. Renewable Energy Sources for rural areas in Asia and Pacific, APO, Tokyo,
2000
3. www.ireda.org
4. www.windenergy.com

Bureau of Energy Efficiency 161

 Appropriate Technology

Engr 10
Introduction to Engineering
Prepared by Pat
Backer, 3/19/08
Tech Adoption
Worldwide
• For the past 3 years,
China has been the
world’s largest importer
of ICT
• In India, 50% of all
urban dwellers have
mobile or fixed
telephones; however,
only 6% of rural Indians
have phones
 Tech Diffusion
• Technology is spreading
to emerging markets
faster than ever before
• The technology lag is
decreasing
• New technologies are
entering developing
countries and
“leapfrogging” over older
technologies (i.e., cell
phones)
Rates of Tech Diffusion
• Tech diffusion is lowest in Latin American
countries
• Less than 2% of the business workforce in Chile
and Brazil are in ICT, Why?
– Inward-looking economic policies
– Import restrictions on technology
– Problems in the educational systems
– Less money is spent on R&D: Developed countries
spend 2.3% GDP on R&D, East Asian, 1.4%. But,
Latin America spends only 0.6%
What is appropriate technology?

• Appropriate technology has been used to cover a wide

range of both technologies and lifestyles including
sustainable living, alternative fuels, and ethical
technology transfers.
• A technology is considered appropriate if it solves a
social problem without many adverse negative effects.
• Every new technology has consequences for society. A
technology is appropriate when its intended positive
consequences outweigh its unintended negative
consequences
How do we evaluate appropriateness?

• There are three ways of evaluating appropriateness:

technical, cultural, and economic.
– Technical--considering the technical knowledge and
background of the people who will be using this
technology.
– Cultural—the relationship of the technology to the
critical social systems in the society including family
systems, religious beliefs, division of labor in a
society, and levels of education and training.
– Economic--a technology's effect on income levels and
income distribution in a society and income disparity
between different socio-economic groups.
 Factors for the assessment of an appropriate
technology
• Various factors for assessment of appropriateness would include the
following1:
– What is the need?
– Is there an adequate business environment in place for this
technology?
– What is the best technical option for the transfer? (Some issues
include the requirements for operating the technology, repair facilities
for the technology, scope of the technology)
– What are the possible unintended negative effects of the technology?
– What are the broader cultural, political and/or social effects of the
technology?

Everts, S. (1998). Gender and technology. Empowering women,

engendering development. New York: Zed Books, p 34.
Examples of appropriate technologies

• Renewable Energy
• Smart Growth
• Green Buildings

Please click on the topic above to read more

about each of these appropriate technologies
Renewable Energy

• Renewable energy industries produce energy using

resources such as sunlight, wind, water current, and
organic waste
• Renewable sources of energy are diffuse (spread thin)
and intermittent. One example of the diffuseness feature
is that a 1000‑megawatt solar farm might occupy about
5000 acres of land, while a nuclear power station with
the same generating capacity only requires around 150
acres.
Examples of Renewable Energy--Biomass

• Many developing countries depend on wood and

agricultural waste for energy.
• Almost half of India's and nearly 90 percent of total
energy consumption in several small countries in Africa
is provided by wood.
• Sweden has increased its use of biomass dramatically in
the last ten years and presently uses fast-growing willow
trees and other organics to supply 20 percent of its total
energy supply.
 450

Examples of 400
China

Canada

Renewable Energy--
350 Brazil

300

Hydropower

Billion Kilowatthours
United States

250

200

Modern large hydropower 150

Russia

Norway

plants are very expensive 100

India

to build; however,
Japan Sweden
France
50

hydropower is not 0

distributed equally Top Hydroelectric Generating Countries. Source: Energy Information

Administration, US Department of Energy.
around the world.
In the US, about 10 percent of the total electricity is
generated from hydropower. It has dropped since the 1940s
when 40 percent of the electricity in the US was hydropower.

Disruption of the environment is the major reason why there

are fewer hydropower plants being built today.
Examples of Renewable Energy--Geothermal
Energy

• The Philippines has the highest percentage of power

generated from geothermal sources; 22 percent of its
electricity is generated with geothermal steam.
• The percentage of geothermal is high (at least 10-20
percent of the total) in four other countries: Costa Rica,
El Salvador, Kenya, and Nicaragua.
• Central America, parts of Southeast Asia, and the
western United States have the greatest potential for
major reliance on geothermal energy. Promising sites
also exist in parts of southern Europe and East Africa.
 Examples of Renewable Energy--Wind
Experts in the field of alternative energy feel wind energy is the most
auspicious (favorable) of the renewables. Windmills mechanically turn
turbines without an intermediate stage of heating water.

In the early 1980s, more than 8000 wind

machines were installed in California.
One of the largest wind farms is presently
found in the rolling, windswept hills of
the Altamont Pass, east of San
Francisco.

Attempts to reap economies of scale by

building larger windmills capable of
generating more than one megawatt of
power have been suppressed by
Click on graph to see an enlarged view technical problems. Capital costs have
remained prohibitive.
Examples of Renewable Energy—The Ocean
• Three methods for extracting energy from the sea have been
reviewed seriously: wave power, ocean thermal energy conversion,
and tidal power.
– Wave Power aims to harness the motion of the waves using a
variety of devices.
– Ocean thermal energy conversion seeks to exploit the temperature
differences between the warm surface layer and the colder deep
waters of the world's oceans.
– Tidal power is similar to hydroelectric power in the sense it is
severely restricted by geography. It requires long, tapering bays
that drive the tide into a large bore as it moves along the channel.
The incoming tide can then be trapped behind a barrier of some
sort and ultimately used to drive turbines on its way out again.
Examples of Renewable Energy--
Photovoltaic Cells
A conference room covered in
photovoltaic cells at the Bewag power
plant in Berlin. © Wolfgang Hoffmann
http://www.wnrmag.com/stories/2003/feb03/en
ergy.htm

• Semi‑conductors have the unique property of being able

to turn sunlight directly into electric current. This
application is surfacing in a variety of items such as
solar‑powered calculators, refrigerators, and satellites.
• According to some energy forecasters, solar cells installed
on rooftops may allow for a much greater
decentralization of electricity than other technologies.
Examples of Renewable Energy--Thermal
Solar Power

Solar thermal power

technologies and solar
ponds are projected to
have competitive
generating costs by the
end of the century. The
capital cost for expensive
items like polished
mirrors to track the path
http://www.sandiego.edu/weather/images/
of the sun is presently N/solar_thermal_power_plant.jpg

exorbitant. Click on diagram to see enlarged picture

 Solar Two

Example: Solar Two—the solar energy was collected

through a field of individually guided mirrors, called
heliostats. The sunlight heats salt to 1,050 degrees
Fahrenheit, which turns the salt into a liquid (or molten
salt). The liquid and hot salt was then piped away, stored,
and used to power a steam turbine.
• Return to Main Menu
Smart Growth
• Smart growth is development that accommodates the
needs of a community without sacrificing the
environment.
• Smart growth aims to balance development and
environmental protection by creating new developments
that are:
– centered more in the towns and cities
– include alternative transit options (trains, bike paths, and safe
walkways)
– have mixed use development.
• Mixed use development moves away from the post-WWII
ideal of single-home-only suburbs to a model that
includes housing, commercial, and retail space in the
same development.
Types of Smart Growth
• Smart growth means that less land can accommodate new
development: this development is sometimes called
compact development. There are three common
techniques to achieve compact development: infill
development, brownfields redevelopment, and cluster
development.
Infill development

Infill development is
development that
attempts to add
additional housing or
business facilities
inside an existing
development. This
way, a city can fill up
unused space in a
particular area. An example of a recent mixed use development is the
Paseo Colorado complex in Pasadena, California. The new
complex was built in center of town and includes a two-
level shopping center with four stories of apartments above
the shopping areas.
Cluster development

Cluster development allows for similar dwellings as

does “regular” developments; however, the
individual lot sizes are reduced and room is left
for open spaces in the development
Brownfields redevelopment

Brownfields redevelopment is development that targets the

empty factories inside the city and develops them into
new living and/or retail space. One of these former
DelMonte canneries, Plant 51, is the site of a brownfield
development to convert the cannery into lofts.
• Return to Main Menu
Green Buildings
• Buildings are a major source of air pollution in the US.
According to the US Department of Energy
• Buildings emit
– 52 percent of all sulfur dioxide
– 19 percent of all nitrous oxide
– 38 percent of carbon dioxide
– 5 percent of particulate emissions
• Considering the number of homes and businesses in the
US—over 76 million residential and 5 million
commercial buildings at last count—this problem is
considerable.
Techniques used in Green Construction

• Designing energy
efficient buildings.
Energy efficiency is
the most important
factor in green
construction.
The Solectrogen House is an off-grid PV-powered
residence in Nicasio, CA. It was designed to use
active and passive solar energy, serve as a live-in
laboratory for energy conservation and alternative
energy products, and be a comfortable, traditionally
attractive home with all the conveniences of modern
living. Source:
http://www.nrel.gov/data/pix/Jpegs/04479.jpg
Techniques used in Green Construction
• Reducing material use in construction. Smaller is better
for the environment; using less materials is always
preferable from an environmental point of view.
• However, the trend today is for houses to get larger and
larger.
• Using low-impact materials during construction.
– Many construction and building materials contain toxins. Many
types of carpeting, for example, emit gases as they age.
– Research has found, particularly in houses that are tightly
sealed, that their exposures to dangerous chemicals and
pesticides is much higher inside the house rather than outside
the house.
• Return to Main Menu
Sustainable Agriculture

• Sustainability is built upon three broad goals: farm

profitability, improvement of the environment, and
increased quality of life for farmers and their
communities.
 Practices used in sustainable agriculture
• Integrated pest management (IPM) is
a system for managing pests to keep
them at levels where they cause
minimal damage to crops.
• Conservation tillage--any plowing
system that leaves at least 30
percent of the soil surface covered
with residue from the year’s
plantings. This is done so that there
will be enough soil coverage to
decrease soil erosion.
Rows of soybean plants emerge from a field covered with old corn stalks from the previous harvest. These
soybeans were planted in narrower (15-inch) rows because as they mature their big leaves will quickly shade the
ground, making it harder for the sun to warm weed seeds that may lie between the rows. This natural canopy
from the growing soybean plants can help farmers reduce the need for herbicides (weed killers). (CTIC/Towery
photo) Source: http://www.ctic.purdue.edu/Core4/CT/images/cornsoytt.jpg [2002, February 4].
Practices used in sustainable agriculture
• Enhanced nutrient management
includes testing of the soil before
using any fertilizer. The goal of
nutrient management is to minimize
unused nutrients.
• Precision agriculture is the newest
and the most technology-intensive
technique in sustainable agriculture.
Precision agriculture uses information
technologies including global
positioning systems (GPS) and
remote sensing to achieve optimal
farming outputs.
• Return to Main Menu
Click on graph to return to presentation
Click on diagram to return to presentation