Introduction to Energy Auditing

1. By
Saravanan T Y
Assistant Professor
EEE Department
NEC Gudur

2. Course Objectives
The objectives of the course are to make the students:
1. To learn about energy consumption and situation in India.
2. To learn about Energy Efficient Motors and Power Factor
Improvement.
3. To learn about Energy Measuring Instruments.
4. To understand the Demand Side Management.
5. To understand economics and cost effectiveness tests of DSM
Programs.

3. Course Syllabus
UNIT-I: INTRODUCTION TO ENERGY AUDITING
Energy Situation World and India, Energy Consumption, Conservation, Codes,
Standards and Legislation. Energy Audit- Definitions, Concept, Types of Audit,
Energy Index, Cost Index, Pie Charts, Sankey Diagrams, Load Profiles,
Energy Conservation
Schemes. Measurements in Energy Audits, Presentation of Energy Audit
Results.
UNIT – II : ENERGY EFFICIENT MOTORS AND POWER FACTOR
IMPROVEMENT
Energy Efficient Motors , Factors Affecting Efficiency, Loss Distribution,
Constructional Details , Characteristics - Variable Speed , Variable Duty Cycle
Systems, RMS Hp- Voltage Variation-Voltage Unbalance- Over Motoring-
Motor Energy Audit. Power Factor Methods of Improvement, Power factor With
Non Linear Loads

4. UNIT –III: LIGHTING AND ENERGY INSTRUMENTS FOR AUDIT
Good Lighting System Design and Practice, Lighting Control, Lighting Energy
Audit - Energy Instruments- Watt Meter, Data Loggers, Thermocouples,
Pyrometers, Lux meters, Tong Testers, Applications of PLC.
UNIT – IV: INTRODUCTION TO DEMAND SIDE MANAGEMENT
Introduction to DSM, Concept of DSM, Benefits of DSM, Different Techniques
of DSM, Time of Day Pricing, Multi-Utility Power Exchange Model, Time of
Day Models for Planning. Load Management, Load Priority Technique, Peak
Clipping, Peak Shifting, Valley Filling, Strategic Conservation, Energy Efficient
Equipment. Management and Organization of Energy Conservation
Awareness Programs.

5. UNIT – V: ECONOMICS AND COST EFFECTIVENESS TESTS OF DSM
PROGRAMS
Basic payback calculations, Depreciation, Net present value calculations.
Taxes and Tax Credit Numerical Problems. Importance of evaluation,
measurement and verification of demand side management programs. Cost
effectiveness test for demand side management programs - Ratepayer
Impact Measure Test, Total Resource Cost, Participant Cost Test, Program
Administrator Cost Test Numerical problems: Participant cost test, Total
Resource Cost test and Ratepayer impact measure test.

6. Course Outcomes
At the End of Course, The student should be able to:
1. Conduct energy auditing and evaluate energy audit results.
2. Carry out motor energy audit.
3. Conduct energy auditing for lighting and Carry out energy instruments
for audit.
4. Analyze demand side management concepts through case study.
5. Analyze economics and cost effectiveness tests of DSM programs.

7. Introduction to Energy
Energy is one of the major inputs for the economic development
of any country. In the case of the developing countries, the energy sector
assumes a critical importance in view of the ever-increasing energy
needs requiring huge investments to meet them.
Energy can be classified into several types based on the following
criteria:
1. Primary and Secondary energy
2. Commercial and Non commercial energy
3. Renewable and Non-Renewable energy

8. 1. Primary and Secondary Energy
Primary energy sources are those that are either found or stored
in nature. Common primary energy sources are coal, oil, natural gas, and
biomass (such as wood).

9. 1. Primary and Secondary Energy
• Other primary energy sources available include nuclear energy from
radioactive substances, thermal energy stored in earth's interior, and
potential energy due to earth's gravity.
• The major primary and secondary energy sources are shown in above.
Primary energy sources are mostly converted in industrial utilities into
secondary energy sources; for example coal, oil or gas converted into
steam and electricity.
• Primary energy can also be used directly. Some energy sources have
non-energy uses, for example coal or natural gas can be used as a
feedstock in fertilizer plants.

10. 2. Commercial Energy and Non Commercial Energy
Commercial Energy
• The energy sources that are available in the market for a definite price
are known as commercial energy.
• By far the most important forms of commercial energy are electricity,
coal and refined petroleum products. Commercial energy forms the
basis of industrial, agricultural, transport and commercial
development in the modern world.
• In the industrialized countries, commercialized fuels are predominant
source not only for economic production, but also for many household
tasks of general population.
• Examples: Electricity, lignite, coal, oil, natural gas etc.

11. 2. Commercial Energy and Non Commercial Energy
Non-Commercial Energy
• The energy sources that are not available in the commercial market for
a price are classified as non-commercial energy.
• Non-commercial energy sources include fuels such as firewood, cattle
dung and agricultural wastes, which are traditionally gathered, and
not bought at a price used especially in rural households.
• These are also called traditional fuels. Non-commercial energy is often
ignored in energy accounting.
• Example: Firewood, agro waste in rural areas; solar energy for water
heating, electricity generation, for drying grain, fish and fruits; animal
power for transport, threshing, lifting water for irrigation, crushing
sugarcane; wind energy for lifting water and electricity generation.

12. 3. Renewable and Non-Renewable Energy
Renewable Energy
• Renewable energy is the energy obtained from sources that are
essentially inexhaustible.
• Examples of renewable resources include wind power, solar power,
geothermal energy, tidal power and hydroelectric power.
• The most important feature of renewable energy is that it can be
harnessed without the release of harmful pollutants.
Renewable Energy Non-Renewable Energy
Non-Renewable Energy
• Non-renewable energy is the conventional fossil fuels such as coal,
oil and gas, which are likely to deplete with time.

13. Global Primary Energy Reserves
Coal
• The proven global coal reserve was estimated to be 1070 billion tonnes by
end of 2019.
• The USA had the largest share of the global reserve (23%) followed by
Russia (15%), Australia (14%), China (13%). India has 9%.
Oil
• The global proven oil reserve was estimated to be 1733.9 billion barrels by
the end of 2019.
• Saudi Arabia had the largest share of the reserve of 297.6 with almost
17.16%. (One barrel of oil is approximately 160 litres)
Gas
• The global proven gas reserve was estimated to be 176 trillion cubic
metres by the end of 2019.
• The Russian Federation had the largest share of the reserve with almost
27%.

14. Energy Situation in India
Reserves and Potential for Generation
• India’s energy-mix comprises both non-renewable (coal, lignite,
petroleum and natural gas) and renewable energy sources (wind,
solar, small hydro, biomass, cogeneration biogases etc.,).
• Information on reserves of non-renewable sources of energy like coal,
lignite, petroleum, natural gas and the potential for generation of
renewable energy sources is a pre- requisite for assessing the country’s
potential for meeting its future energy needs.
• They also facilitate in devising effective conservation and
management strategies for optimal utilization of these resources.

15. Coal and Lignite
• India has a good reserve of coal and lignite.
• As on 2018, the estimated reserves of coal was around 286 billion
tones, an addition of 9 billion over the last year.
• The states of Jharkhand, Orissa, Chhattisgarh, West Bengal, Andhra
Pradesh, Maharashtra and Madhya Pradesh account for more than 99%
of the total coal reserves in the country.
• The total estimated reserve of coal in India as on 2017 was around 277
billion tons.
Petroleum and Natural gas
• The estimated reserves of crude oil and natural gas in India as on 2018
stood at 757 million tons (MT) and 1241 billion cubic meters (BCM),
respectively .

16. • Geographical distribution of Crude oil indicates that the maximum
reserves are in the Western Offshore (43%) followed by Assam (22%),
whereas the maximum reserves of Natural Gas are in the Eastern
Offshore (35%) followed by Western offshore (33%).
• There was an increase of estimated Crude Oil reserves by 33% in
Andhra Pradesh followed by Tamil Nadu (8%).

17. Energy Requirement at a Glance

18. Renewable Energy Sources
• There is high potential for generation of renewable energy from
various sources-wind, solar, biomass, small hydro and cogeneration
bagasse.
• The total potential for renewable power generation in the country as on
2018 is estimated at 89760 MW.
• This includes an estimated wind power potential of 49132 MW (55%),
SHP (small-hydro power) potential of 15,385 MW (17%), Biomass
power potential of 17,538 MW(20%) and 5000 MW (6%) from bagasse-
based cogeneration in sugar mills.
Installed Generating Capacity of Electricity
• The total installed capacity for electricity generation in the country has
increased from 6,271 MW as on 31.03.1971 to 206,526 MW as on
31.03.2011, registering a Compound Annual Growth Rate (CAGR) of
6.4%.

19. Generation of Electricity through Conventional Energy Sources
• The all India gross electricity generation from utilities, excluding that
from the captive generating plants, was 55,828 Giga Watt-Hours
(GWh) during 1970-71.
• It rise to 1,10,844 GWh during 1980-81, to 2,64,329 GWh during 1990-
91 and to 8,44,846 GW during 2010-11.

20. Energy Situation in World
• With the present situation of increasing energy demand, rising energy
prices, and reinforcement of countermeasures for global warming,
renewable energy sources have taken the spotlight.
• Bio-fuels are one form of renewable energy that has become more
widespread.
• Also, bio-fuels have been introduced and expanded as alternative fuel
for the transportation sector and as a form of liquid renewable energy
that can be blended with petroleum.
Items
Energy Demand (Mtoe)
1980 2000 2005 2015 2030
Total Primary energy demand 7,223 10,034 11,429 14,121 17,014
Petroleum Oil 3,107 3,649 4,000 4,525 5,109
Transport 1,245 1,936 2,011 2,637 3,171
Petroleum 1,187 1,844 1,895 2,450 2,915
Bio-fuels 2 10 19 74 118
Other fuels 57 82 96 113 137
*Mtoe – Million ton of oil Equivalent

21. Transportation Sector
• The reason petroleum accounts for a large fraction of energy supply for
the transportation sector is that petroleum alternatives are difficult.
• Petroleum fuels for airplanes, ships and automobiles have several key
merits.
Global Environmental Problems
• Discussions on environmental problems in energy policy, particularly
global warming issues, have been given much attention these days.
• Currently, the amount of fossil fuel origin carbon dioxide discharge has
been increasing, with the corresponding increase in energy demand.
• Due to this increase, it has been strongly claimed that the artificial
greenhouse effect is the main cause.

22. Energy Conservation
Importance
• December 14th is celebrated as World Energy Conservation day, we
can conserve energy and find out why energy conservation is so
important.
• Energy conservation means making an effort to reduce the
consumption of natural energy sources like electricity, water and so
on.
• Coal and other fossil fuels, which have taken three million years to
form are likely to deplete soon.
• In the last two hundred years, we have consumed 60% of all resources.
• For sustainable development, we need to adopt energy efficiency
measures.
• Today, 85% of primary energy comes from non-renewable and fossil
sources (coal, oil, etc.).

23. Energy Conservation in India
• India has made rapid strides towards economic self-reliance over the
last few years.
• However, India’s fossil fuel reserves are limited.
• The known reserves of oil and natural gas may last hardly for 18 and 26
years respectively at the current reserves to production ratio.
• On the other hand, the demand for energy is growing manifold and
the energy sources are becoming scarce and costlier.

24. Energy Demand and Supply
• On the energy demand and supply side, India is facing severe
shortages. 70% of the total petroleum product demand is being met
by imports, imposing a heavy burden on foreign exchange.
• Country is also facing Peak power and average energy shortages of
12% and 7% respectively.

25. Energy Consumption
• Electric energy consumption is the form of energy consumption that
uses electric energy.
Overview
• Consumption of electric energy is measured by Wh (Watt x Hour)
• 1 Wh = 3600 joule = 859.8 calorie
• One 100 watt light bulb consumes 876,000 Wh (876 KWhr) of energy in
one year.
• Electric/Electronics devices consume electric energy to generate
desired output (i.e. light, heat, kinetic etc.), while its operation some part
of energy are consumed in unintended output.
• In 2018, world total of electricity production and consumption was
22261TWh.
• This number corresponds to a "consumed" power of around 2.3 TW on
average.

26. Consumption of Electricity in India
• The estimated electricity consumption increased from 43,724 GWh
during 1970-71 to 6,94,392 GWh during 2010-11, showing a CAGR
(Compound Annual Growth Rate) of 6.98%.
• The increase in electricity consumption is 13.34% from 2009-10
(6,12,645 GWh) to 2017-18 (6,94,392 GWh).
• Of the total electricity sales in 2010-11, industry sector accounted for the
largest share (38.6%), followed by domestic (23.8%), agriculture
(19.6%) and commercial sector (9.89%).
Consumption of coal and lignite in India
• The estimated total consumption of raw coal by industry has increased
from 71.2 MTs during 1970-71 to 592.99 MTs during 2010-11, with a
CAGR of 5.3%.
• Consumption of Lignite is highest in Electricity Generation sector,
accounting for about 79% of the total lignite consumption.

27. Definition of Electricity - Consumption:
• This entry consists of total electricity generated annually plus imports
and minus exports, expressed in kilowatt-hours.
• The discrepancy between the amount of electricity generated and/or
imported and the amount consumed and/or exported is accounted for as
loss in transmission and distribution.

28. Energy Conservation Standards & Labeling
• Standards and Labeling (S & L) has been identified as a key activity
for energy efficiency improvement. The S & L program, when in place
would ensure that only energy efficient equipment and appliance
would be made available to the consumers. The main provision of EC
act on Standards and Labeling are:
 Evolve minimum energy consumption and performance
standards for notified equipment and appliances.
 Prohibit manufacture, sale and import of such equipment,
which does not conform to the standards.
 Introduce a mandatory labeling scheme for notified equipment
appliances to enable consumers to make informed choices.
 Disseminate information on the benefits to consumers.

29. Energy Conservation Standards & Labeling
• The actual number of products manufactured and
sold in each Star category was taken from
manufacturers
• The Energy Efficiency Ratio (EER) has been
considered individually for all the products.
• The Star 0 (EER – 2.2) has been used as baseline
for the calculation of Energy Savings due to the star
rated products.
• An average of 150 working days in a year was
considered.
• An average of 8 working hours in a day was
considered.
• The coincidence factor considered is 1 for
estimating avoided capacity.

30. Air Conditioners
• In order to estimate the savings of electricity from star labeled Air-
conditioners, following methodology has been used.
• The actual number of products manufactured and sold in each Star
category was taken from manufacturers.
• The Energy Efficiency Ratio (EER) has been considered individually
for all the products.
• The Star 0 (EER – 2.2) has been used as baseline for the calculation of
Energy Savings due to the star rated products.
• An average of 150 working days in a year was considered.
• An average of 8 working hours in a day was considered.
• The coincidence factor considered is 1 for estimating avoided capacity.

31. Legislation
Electricity
• Electricity Regulatory Commission Legislation, the Central Electricity
Regulatory Commission (CERC) was set up, with the main objective
of regulating the Central power generation utilities.
• State level regulatory bodies have also been set up to set tariffs and
promote competition.
• Private investments in power generation were also allowed.
• The State SEBs were asked to switch over to separate Generation,
Transmission and Distribution corporations.
• There are plans to link all SEB grids and form a Unified National
Power Grid.

32. Electricity Act, 2003
• The government has enacted Electricity Act, 2003 which seeks to
bring about a qualitative transformation of the electricity sector.
• Indian Electricity Act, 1910, the Electricity (Supply) Act, 1948 and the
Electricity Regulatory Commissions Act, 1998.
• The objectives of the Act are "to consolidate the laws relating to
generation, transmission, distribution, trading and use of
electricity and generally for taking measures conducive to development
of electricity industry, promoting competition therein, protecting interest
of consumers and supply of electricity to all areas, rationalization of
electricity tariff.

33. Introduction to Energy Management
Objectives
The fundamental goal of energy management is to produce
goods and provide services with the least cost and least
environmental effect.
• The term energy management means many things to many people.
One definition of Energy Management is
"The judicious and effective use of energy to maximize
profits (minimize costs) and enhance competitive positions"
Another comprehensive definition is
"The strategy of adjusting and optimizing energy, using
systems and procedures so as to reduce energy
requirements per unit of output while holding constant or
reducing total costs of producing the output from these systems"

34. The objective of Energy Management is to achieve and maintain
optimum energy procurement and utilization, throughout the
organization and:
• To minimize energy costs / waste without affecting production &
quality.
• To minimize environmental effects.
ENERGY AUDIT
• The main purpose of Energy Audit is to increase energy efficiency,
and reduce energy related costs.
• It involves collection of detailed data and its analyses. More often
sophisticated instruments are used to collect data, but its analyses and
interpretation requires technical knowledge, experience, and sound
judgment.

35. Energy Audit is a fundamental part of an Energy Management
Programme (EMP) in controlling energy costs. It will identify areas of
wasteful and inefficient use of energy.
• As per the 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".

36. Types of Plant Energy Studies
The type of Energy Audit to be performed depends on:
• Function and type of industry
• Depth to which final audit is needed, and
• Potential and magnitude of cost reduction desired
• There are mainly two types of Energy Audit, viz.
1. Preliminary Energy Audit (PEA)
2. Detailed Energy Audit (DEA)

37. Preliminary Energy Audit (PEA) / House Keeping Practices
• Considerable savings are possible through small improvements in the
“house keeping” practices, and the cumulative effect of many such
small efficiency improvements could be quite significant.
• These can identify by a short survey, observation and
measurements. Many energy conscious industries have already
achieved considerable progress in this area.
Approach to Preliminary Energy Audit (PEA)
• This is essentially involves preliminary data collection and analyses.
• The PEA is based on collection of available data, analysis,
observation, and inference based on experience and judgment is
carried out within a short time.

38. Preliminary Energy Audit (PEA) / House Keeping Practices
• The PEA is the first step in implementing an energy conservation
programme, and consists of essentially collecting and analyzing data
without the use of sophisticated instruments.
• The ability and experience on the part of Energy Auditor will influence
the degree of its success.
• Preliminary Energy Audit is carried out in six steps:
1. Organize resources
2. Identify data requirements
3. Collect data
3. Analyze data
4. Develop action plan
5. Implementation

39. 1. Organize resources
• Manpower / time frame
• Instrumentation
2. Identify data requirements
• Data forms
3. Collect data
 Conduct informal interviews
• Senior management
• Energy manager/coordinator
• Plant engineer
• Operators and production management and personnel
• Administrative personnel
• Financial manager

40.  Conduct plant walkthrough/visual inspection
• Material/energy flow through plant
• Major functional departments
• Any installed instrumentation, including utility meters
• Energy report procedures
• Production and operational reporting procedures
• Conservation opportunities
4. Analyze data
 Develop data base
• Historical data for all energy suppliers
• Time frame basis
• Other related data
• Process flow sheets
• Energy consuming equipment inventory

41.  Evaluate data
• Energy use consumption, cost, and schedules
• Energy consumption indices
• Plant operations
• Energy savings potential
• Plant energy management program
• Preliminary energy audit
5. Develop action plan
• Conservation opportunities for immediate implementation and
Projects for further study
• Resources for detailed energy audit
• Systems for test
• Instrumentation; portable and fixed
• Manpower requirements, Time frame
• Refinement of corporate energy management programme

42. 6. Implementation
• Implement identified low cost/no cost projects
• Perform detailed audit
Preliminary Energy Audit Methodology
Preliminary energy audit is a relatively quick exercise to:
• Establish energy consumption in the organization
• Estimate the scope for saving
• Identify the most likely and the easiest areas for attention
• Identify immediate (especially no-/low-cost)
improvements/savings
• Set a 'reference point'
• Identify areas for more detailed study/measurement

43. DETAILED ENERGY AUDIT (DEA)
• DEA is a comprehensive energy efficiency study using portable
energy monitoring instruments.
• The essential part of this audit is carrying out various measurements
and analyses covering individually every significant energy
consuming plant item/processes, to determine their efficiencies and
loss of energy at that point, and potential energy savings are explored
and crystallized, and every recommendation for investment is supported
by criteria such as pay-back analysis.
• Data generation and collection is an essential and critical element of
a detailed energy audit study.
• The acquisition of actual operating data through existing or new
permanently installed instruments or portable test instruments cannot be
overemphasized in this context.

44. Steps followed in Detailed Energy Audit (DEA)
STEP
No
PLAN OF ACTION PURPOSE / RESULTS
Step-1 Phase-I: Pre Phase Audit
 Plan and Organize
 Walk through Audit
 Informal Interview with
Energy Manager,
Production / Plant
Manager
 Resource planning, Establish / organize
a Energy audit team.
 Organize Instruments & time frame
 Macro Data collection (suitable to type of
industry.)
 Familiarization of process / plant
activities
 First hand observation & Assessment of
current level operation and practices.
Step-2  Conduct of brief meeting
/ awareness programme
with all divisional heads
and persons concerned
(2-3 hrs.)
 Building up cooperation
 Issue questionnaire for each department
 Orientation, awareness creation.

45. STEP
No
PLAN OF ACTION PURPOSE / RESULTS
Step-3  Phase-II: Audit Phase
 Primary data gathering,
Process Flow Diagram,
& Energy Utility Diagram
 Historic data analysis, Baseline data
collection
 Prepare process flow charts
 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 and
monitoring
 Measurements:
 Motor survey, Insulation, and Lighting
survey with portable instruments for
collection of more and accurate data.
Confirm and compare operating data
with design data.

46. STEP
No
PLAN OF ACTION PURPOSE / RESULTS
Step-5  Conduct of detailed trials
/ experiments for
selected energy
guzzlers
 Trials/Experiments:
 24hours power monitoring (MD, PF, kWh
etc.).
 Load variations trends in pumps, fan
compressors etc.
 Boiler/Efficiency trials for (4-8 hours)
 Furnace Efficiency trials Equipments
Performance experiments etc.,
Step-6  Analysis of energy use  Energy and Material balance & energy
loss/waste analysis.
Step-7  Identification and
development of Energy
Conservation (ENCON)
opportunities.
 Identification & Consolidation ENCON
measures.
 Conceive, develop, and refine ideas
 Review the previous ideas suggested by
unit personal
 Review the previous ideas suggested by
energy audit if any
 Use brainstorming and value analysis
techniques
 Contact vendors for new/efficient
technology.

47. STEP
No
PLAN OF ACTION PURPOSE / RESULTS
Step-8  Cost benefit analysis  Assess technical feasibility, economic
viability and prioritization of ENCON
(Energy Conservation) options for
implementation.
Step-9  Reporting &
Presentation to the Top
Management
 Documentation, Report Presentation to
the top Management.
Step-10  Phase-III: Post Audit
Phase
 Implementation and
Follow-up
 Assist and Implement ENCON
recommendation measures and Monitor
the performance
 Action plan, Schedule for
implementation
 Follow-up and periodic review

48. Energy Consumption Monitoring
• Energy Consumption is to monitor, assess by a company / industry
and compared with a specific products manufactured by the industry
can be done by two parameters as follows.
They are,
1. Energy Index
2. Cost Index
1. Energy Index
• Energy index is a useful parameter to “monitor and compare energy
consumption of specific products manufactured by the industry”.
• Energy index is the figure obtained by dividing energy consumption by
production output, and the index may be calculated weekly, monthly or
annually.

49. • Although the total energy indices are sufficient for monitoring
purposes, a record of the individual energy indices should be
maintained.
• In the event of an increase or decrease (due to perhaps a conservation
measure) in energy index, the particular source can be investigated
immediately.
• Energy may be purchased in various units, for example, coal in tons;
gas in ft3,m3, therms; oil in gallons, litres, tons, barrels etc. the relevant
conversion units from one system to the other.
• To determine the heat available from the fuel, it is necessary to know the
calorific value per unit quantity of energy form.
Energy Index EI =
total energy consumption
total production output
(based on weekly, monthly & annually)

50. Example 1:
An office block uses 40*103 gallons of fuel oil per year for heating
purposes. The calorific value is 175*103 Btu/gal. The fuel
consumption may be expressed in litres or m3.
Sol:
40*103*4.545 litres = 182*103 litres = 182 m3
The calorific value may be quoted as 103 J/litres
175*103 Btu/gal = 175*103*0.2321*103 J/l
= 40600*103 J/l = 40.6*106 J/l
The total theoretical heat available becomes:
40*103 gal *175*103 Btu/gal= 7.00*109 Btu/year
182*103 I * 40600 *103 Btu/gal = 7.39*109 J/year
182 m3 *40.6*106 Btu/gal = 7.39*109 J/year

51. 2. Cost Index
• The cost index is another parameter which can be used to “monitor and
assess energy consumption by a company”.
• The cost index is defined as the cost of energy divided by the
production output.
• An individual cost index can be determined for each energy form and for
the total energy consumption by the company.
Cost Index CI =
total cost of energy
total produc tion output

52. Example 1:
Table below shows energy costs for a company using coke, gas
and electricity. This company produces 15*103 tons per year.
Calculate cost indices.
Sol:
Coke cost index = 108.0*103 / 15*103 (tons) = Rs. 7.2/ton
Gas cost index = 3.6*103 / 15*103 (tons) = Rs. 0.2/ton
Electricity cost index = 22.5*103 / 15*103 (tons) = Rs. 1.5/ton
Total cost index = 134.1*103 / 15*103 (tons) = Rs. 8.9/ton

53. Representation of Consumption
• Several methods of representing energy flows and energy consumption
are available and these may be graphical or tabular. Most among them
are the “pie chart and the sankey diagram”.
Pie Chart
• Energy usage is plotted on a circular chart where the quantity of a
particular type is represented as a segment of a circle.
• The size of the segment will be proportional to the energy consumption
using a particular fuel (energy form or source) relative to total energy
use.
• The energy units must be rationalized to the same units.

54. Example:
A company uses on an hourly basis 11.72*103 therms of gas, 500*103 W
electricity and 4.32*109 J oil. Represent these energy consumptions in a
pie chart.
Sol:
The results may all be expressed in watts as follows:
Gas = 11.72*103 / 29.31*10-3 = 400*103 W
Electricity = 500*103 W
Oil = 4 .32*109*0.278*10-3 = 1200*103 W
Total hourly energy consumption = 2100* 103 W
The pie chart can be represented as follows

55. Gas
68
Oil
206
Electricity
86
Energy Consumption
Gas Oil Electricity
Consequently, the angles occupied by the segment are:
Gas = (400*103/2100*103)*360 = 680
Oil = (1200*103/2100*103)*360 = 2060
Gas = (500*103/2100*103)*360 = 860

56. Measurements in Energy Audit
• Measurements are critical in any serious effort to conserve energy.
• Apart from helping to quantify energy consumption, measurements
also provide a means to monitor equipment performance and check
equipment condition.
• Examples of measurements and instrument types are:
1. Flow/Velocity: Orifice plate, picot tube, Ventura tube, turbine meter,
vortex shedding flow meter, ultrasonic flow meter.
2. Temperature: Thermometers–Bimetallic, Resistance etc.,
Thermocouple, Radiation pyrometer.
3. Pressure: Bourdon gauge, Diaphragm gauge, manometers

57. 4. Stack Gas Analysis: Orsat apparatus, Oxygen analyzers, carbon
dioxide analyzers, Carbon monoxide analyzers.
5. Heat Flow: Thermograph equipment
6. Electrical: Multi-meter, Ammeter, Wattmeter, Power Factor meter,
Light meter
7. Stream Trap Testing: Stethoscope, Ultrasonic Detector

58. Electrical Measuring Instruments
• These are instruments for measuring major electrical parameters such
as kVA, kW, PF, Hertz, VAr, Amps and Volts.
• In addition some of these instruments also measure harmonics.
I. Ammeter: it measures the current absorbed by appliances and
motors.
II. Voltmeter: it measures the voltage or voltage drop in the grid or
electrical circuits.
III. Watt-meter: it measures instant power demand of appliances/motors
or the power performance of generators.
IV. CosΦ-meter: it measures the power factor or monitors the
rectification devices.
V. Multi-meter: it measures all the above quantities

59. VI. 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.
• All the above instruments are usually portable. They are connected to
the wiring with the use of nippers and they could feature a data-logger.
• Measurements of electrical power and energy consumption should be
made on all energy intensive areas and installations.
• Since these instruments are generally not expensive, it is advised to
examine their permanent installation in some of the above cases.

60. Temperature Measurement
• PC-based temperature meters are already available in respective
shops. The most usual measuring technologies include:
I. Resistance Thermometer Detectors (RTD):
From the most technologically advanced instruments. These features
internal signals for calibration and resetting.
II. Thermocouples:
They are widely used and are not expensive. They cover a wide
range of temperatures, from a few degrees up to 10000C and are
usually portable.
They need frequent calibration with specialized instruments. The
main disadvantage is that they have a weak signal, easily affected
by industrial noise.

61. III. Thermistors:
These are used as permanent meters and are of low cost. They are
characterized by a strong, linear in variation with temperature signal
and have an automatic resetting capability.
Still this type and the thermocouple are not usually found in M&V
(Measuring & Verification) set-ups.
IV. Infrared thermometers:
It measures temperatures from a distance by sensing the bodies
thermal radiation.
This is a non-contact type measurement which when directed at a
heat source directly gives the temperature read out. This instrument is
useful for measuring hot spots in furnaces, surface temperatures
etc.

62. Presentation of Energy Audit Report
• Each report should include:
1. Title Page
• Report title
• Client name (company for which facility has been audited)
• Location of the facility
• Date of Report
• Audit contractor name
2. Table of Contents

63. 3. Executive Summary
All information in the Executive Summary should be drawn from
the more detailed information in the full report. The Executive
Summary should contain a brief description of the audit including:
• Name, plant(s), location(s) and industry of the company audited
• Scope of the audit
• Date the audit took place
• Summary of baseline energy consumption presented in table form.
Baseline energy
• Consumption refers to the energy used annually by the
facility/system audited.
• Results:
• Assessment of energy-consuming systems
• Identification of EMOs (Energy Management Opportunity) and the
Estimated Energy, Green House Gas (GHG), e.t.c.,
• Recommendations summarized in table form.

64. 4. Introduction
The Introduction should include:
• Audit Objectives: a clear statement that defines the scope of the
energy audit in clear and measurable terms - example, space(s),
systems and/or process(es) to be audited
• Background Information: a description of the location of the facility
where the audit will be conducted, as well as information regarding
facility layout, products/services produced/distributed, operating hours
including seasonal variations, number of employees and relevant
results of previous energy initiatives.

65. 5. Audit Activity and Results
This section should make reference to:
• Description of the audit methodology (techniques - e.g. inspection,
measurements, calculations, analyses and assumptions)
• Observations on the general condition of the facility and equipment
• Identification / verification of an energy consumption baseline in
terms of energy types, units, costs and greenhouse gas (GHG)
emissions for the facility/system being assessed
• Results of the audit including identification of EMOs and the
estimated energy, GHG, and cost savings.

66. 6. Recommendations
• This section should list and describe the recommendations that flow
from the identification of EMOs and may include details
concerning implementation.
7. Appendices
Appendices include background material that is essential for
understanding the calculations and recommendations and may
include:
• Facility layout diagrams
• Process diagrams
• Reference graphs used in calculations, such as motor efficiency
curves
• Data sets that are large enough to clutter the text of the report.