Energy Efficiency Avenues In Indian Industries
Presented by – R.K. Paul
Senior General Manager- Marketing (Motor)
M:+91 9810 622 768
Email: ravinder.paul@bharatbijlee.com
Date and Place of Presentation in Arial Italic 11 pt

Consumption of electricity by Sector

Why Energy Conservation
 High Cost of generation per MW compared to saving of energy.
 Government of India taking initiative towards energy conservation.
 Win-Win situation for both the user and supplier of energy efficient
equipments.
 Since 2003, there has been a rise of 12.5% in the amount of
electricity consumption in commercial sector.
 Energy is like “raw material” for many energy intensive industries
like Steel,Paper,Textile and so on.

Initiatives taken By Govt. of India
 “Energy Conservation Act” already in place since 2001.
 “Energy Conservation Building Code- 2007(ECBC)” also in place.
This code mentions about HVAC System and motors.
 Energy Audit companies being shortlisted & set up by BEE to
conduct Energy Audits and consultation on profit sharing basis.

Sectors Covered By Energy Conservation Act
 Aluminium Ferilizers
 Iron & Steel Cement
 Pulp & Paper Chlor Alkali
 Sugar Textile
 Chemicals Railways
 Port Trust Transport
 Petrochemicals Power Stations
 Commercial buildings
Note : Number of sectors already purchasing high efficiency motor and reaping
the fruits of low electricity bills and also conserving energy

Regulatory Interventions
 The Government of India has identified the importance of energy
conservation in light of the huge gap between the demand & supply of
power.
 The Government of India had constituted the Bureau of Energy Efficiency
(BEE) as the authority responsible for the implementation of the Act.
 The EC Act identifies energy intensive industries and establishments as
Designated Consumers (DCs) who are required to-
• Appoint or designate an Energy Manager (EM) in their plant.
• Get energy audit conducted by an accredited Energy Auditor (EA)
• Implement techno-economically viable recommendations for energy
conservation
• Comply with fixed norms of specific energy consumption
• Submit reports on the measures taken in a specified format.
 BEE is implementing a labeling program, in preparation to introduction of
Minimum Energy Performance Standards (MEPS) for appliances and
equipment.

Energy Efficient Motors- A National Priority
70% of all electrical energy consumed in India is
used for driving electric motors.
55% of which is consumed by industrial motors

8

National Standard for Energy Efficient Motors

IS 12615: 2004 (First revision) -Superior to existing Std.
IS 8789
 To be considered as energy efficient, a motor must conform to one
of the following efficiency levels specified in IS 12615:

Improved Efficiency (eff 2)

High Efficiency (eff 1)
 eff1 efficiency levels are higher than those of eff2.
 Both eff1 & eff2 are higher than the nominal values specified in IS
8789: 1996.

Range of Energy Efficient Motors
 Eff 2 motors are offered ex-stock by few manufacturers.
 Most of manufacturers offer a complete range of eff 1 motors
against specific orders with a lead time of 8 to 10 weeks. Fast
moving ratings are available of the shelf in case of Bharat Bijlee.

Comparison of efficiencies of Standard & Energy Efficient
Motors
Output IS 8789 eff 2 as per IS eff 1 as per IS
4 Pole 12615 12615
0.75 kW 71.0% 73.0% 82.5%
1.5 kW 76.0% 78.5% 85.0%
3.7 kW 83.0% 84.0% 88.3%
11 kW 85.5% 88.4% 91.0%
18.5kW 87.0% 90.0% 92.2%
37 kW 88.5% 92.0% 93.6%
75 kW Not specified 93.6% 94.7%
110 kW Not specified 94.4% 95.2%
160 kW Not specified 95.0% 95.8%

Salient Features of Eff1 Motors

Why does IS 12615 specify two efficiency levels?
 User has the option to go for eff1 motor and save energy but at
higher initial cost. It is strongly recommended to go for eff1 motor
when utilization is high.
 The standard is hence user friendly since it has provided two levels
of efficiency. This is in line with other international standards like
CEMEP.

How is motor Efficiency Improved
Reduce (1)Iron Loss Reduce (2)Copper Loss
Reduce Reduce
Stator Cu Loss Rotor Cu Loss
Increase
Reduce Copper Section Increase
Flux Density Stator slot area Rotor bar section
Low Loss Increase Reduce Increased
Magnetic matl. Stator Yoke Rotor Diam Starting current
Reduced S t a r t i n g Torque

Efficiency improvement to eff1 by use of Low Loss
Stamping & increased Fe and Cu
11 kW 1500 rpm eff 2 eff1
Low Loss + increased
Stamping Cu & Fe
Iron losses 400 W 330 W 250 W
Friction & Windage 120 W 120 W 120 W
Constant Losses 520 W 450 W 370 W
Load related Losses 840 W 750 W 650 W
Total Losses 1360 W 1200 W 1020 W
Efficiency 89% 90.2% 91.5%

Why is the Energy Efficient motor more expensive?
 eff 1 motors are generally priced 5 - 15 % higher than eff 2 motors.
 More laminations - longer core length and/or
 High Grade (low loss) laminations
 More Copper
Rs.

Life Cycle Cost of Motor
 In one year, a motor consumes energy equivalent to 10 to 20 times its
purchase price.
 Many consumers in India especially OEMs purchase cheap motors having
low efficiency values.

Initial Cost of an 11 kW 4Pole motor is only 4% in the
first year of operation
Assumptions: Efficiency Eff2 : 89.0%
Energy cost: Rs 5 per kWh
Working: 8000 hrs pa

Energy Efficient Motors have a Flat Efficiency Vs Load
Characteristic
 Motor rating is selected for
max. load conditions and next
preferred rating
 Most motors operate on an
average around 75% load.
Efficiency is almost
same from 60% to
100% load in a well
designed EE motor

Energy savings increase at partial loads due to
Flat efficiency vs Load Characteristic
11kW-4 Pole eff 2 motor Vs eff1 motor.
Total Energy saving per annum : Rs. 12112
Additional Price of eff-1 motor over eff2 motor : Rs. 2627
Payback Period is 2.6 Months

Eff1 motor gives further savings over an eff2 motor
Eff2 Eff1
Purchase Price of 11kW/4P
motor Rs 17509 20135
Efficiency 89.0% 91.5%
Energy consumption p.a. for
8000 Hrs @ Rs 4 per kWH 3,95,504 3,84,700
Energy Saving Rs 10804
Additional purchase price Rs 2626
Pay Back Period of eff1 motor is 2.9 months for a 15%
price increase over eff2 motor

Energy Efficient-Increased Safety & Flame Proof
Motors
 Bharat Bijlee offers Flame Proof and Increased Safety motors
conforming to eff2 as standard
 Eff 1 motors can also be offered against customer requirement with
a lead time of 8 to 10 weeks.
 In a few eff1 outputs next higher frame size is required.

Need for High Efficiency Motors
 Use of High efficiency motors in sectors like Fertilizers / Sugar / Central Air-
conditioning units and AHUs/etc, will allow considerable energy saving at
locations with high usage.
 The use of high efficiency motors helps to reduce the power consumption.
 (Example in next slide)
 The following table will provide insights on energy savings on usage of
energy efficient (eff-1) motors against (eff-2), or any other standard motor.
 The ratings in the table correspond to the requirement of a modern building
project, whose enquiry has come up with Bharat Bijlee

Annual Purchase Price PayBack
Rating Efficiency Qty of Savings (Approx) Rs. Price Period
Differenc
HP Pole KW eff2 eff1 Motors Rs. Eff-2 Eff-1 e (Rs.) Months
1.5 4 1.1 78 83.8 1 1969.9 3755 4319 565 3.44
2 4 1.5 80 85 1 2205.9 4108 4721 613 3.34
3 4 2.2 82 86.4 1 2732.6 5427 6243 816 3.58
5 4 3.7 85 88.3 1 3253.6 6944 7990 1046 3.86
7.5 4 5.5 86 89.5 1 5001.9 9570 11008 1438 3.45
10 4 7.5 87 90.3 1 6300.8 11176 12857 1681 3.20
12.5 4 9.3 88 90.5 1 5838.8 17317 20048 2731 5.61
15 4 11 89 91.5 1 6753.9 17891 20573 2682 4.77
20 4 15 90.2 92.2 1 7214.6 22232 25568 3335 5.55
30 4 22 91.8 92.8 1 5164.9 33416 36756 3340 7.76
40 4 30 92 93.2 1 8397.1 45077 49586 4509 6.44
100 4 75 94 94.7 1 11795.4 123421 129594 6172 6.28

Replacement Vs Rewinding -11 kW 4 pole motor
Eff of Old Motor to be rewound or replaced IS 8789 eff2
New motor Efficiency eff2 eff1
Purchase Price of new motor Rs 16000 19200
Rewinding Cost Rs 4000 4600
Additional Cost Rs 12000 14600
Efficiency of old motor 85.5% 88.4%
Efficiency after rewinding ( less 1.5%) 83.0% 86.9%
Efficiency of new motor 88.4% 91.0%
Saving by replacement with new eff2 motor 0.809 kW 0.570 kW
For 5000 Hrs @ Rs 4.0 per kWH (Rs) 16180 11406
Pay back period : 8.9 Months 15.4 Months
Replace old eff 2 motor with eff1 motor & get Payback in 15 months
Replace old IS8789 motor with eff2 motor & get payback in 9 months

Nameplates - Marking of Efficiency
Manufacturer Name Manufacturer Name
3 ph. Induction motor MADE IN INDIA 3 ph. Induction motor MADE IN INDIA
Type MH16M4734 Fr 160M Hz 50 Insl Cl F Type MA16M433 Fr 160M Hz 50 Insl. Cl F
M/c. No . Duty S1 M/c. No . Duty S1
Volts 415 ∆ A 19.7 Eff % 91.5 Volts 415 ∆ A 20.5 Eff % 89.0
kW/HP 11/15 rpm 1460 P f 0.85 kW/HP 11/15 rpm 1450 P f 0.84
EFF-1 EFF-2
A High Efficiency Motor A Standard Motor
(Improved Efficiency)
The EE motors are clearly labeled “EFF-1 or EFF-2”

Inrush current
 Energy-efficient motors feature low electrical resistance and thus exhibit
higher inrush currents than standard models. The inrush current duration is
too short to trip thermal protection devices

Advantages- Apart from Higher Efficiency
• Less maintenance and longer life time due to lower temperature in windings
and bearings
• Higher reliability due to lower losses.
• Better tolerance to thermal stresses resulting from stalls or frequent starting.
• Increased ability to handle overload conditions.
• Better resistance to abnormal operating conditions, such as under and over
 voltage or phase unbalance.
• Higher tolerance to poorer voltage and current wave shapes.

Design Factor to be considered..
• Motor Size. Size motors for efficiency. Motors should be sized to operate
with a load factor between 65% and 100%.
• The common practice of oversizing results in less efficient motor operation.
For example, a motor operating at a 35% load is less efficient than a smaller
motor that is matched to the same load
• The Next figure explains the same.

To Add..
 Energy savings are more at partial loads because Energy Efficient
motors have a Flat Efficiency Vs. Load Characteristic
 Payback period of eff2 motor over IS-8789 motor is approx 1500 working
hrs.
 Payback period of eff1 motor over eff2 motor is approx 2500 working
hrs.

How to Determine Cost effectiveness?
The cost effectiveness of an energy-efficient motor in a specific
situation depends on several factors, such as
 Motor price
 Efficiency rating
 Annual hours of use
 Percent full load
 Energy rates
 Cost of installation and downtime,
 The availability of utility rebates or other incentives.

Advantages of Using High Efficiency Motors

When Should I Consider an Energy-Efficient Motor?
Most motors should be replaced with an energy-efficient model if they operate
over 1500 hours per year. In general, energy-efficient motors should be
considered in the following circumstances:
 New installations, both separate and as part of packages such as HVAC
systems
 When major modifications are made to a facility or a process
 Instead of rewinding old motors, use high-efficiency motors
 Existing motors are under loaded or overloaded.
 As part of a preventive maintenance or energy conservation plan

Intermittent duty applications….?
 Intermittent duty motors are typically used in crane, hoist, valve actuators
and other applications with frequent starts.
 In these applications, motors are designed for low starting losses rather
than low running losses.
For intermittent duty applications EE motors are not the
best choice

Problems in field testing
 Efficiency measurement at site is unreliable.

One needs to decouple the load in order to measure no load losses.

Variable voltage supply required in order to maintain rated voltage.
 We recommend measurement of kWh using a energy meter and
compare two motors.
 Measurement of current is not a reliable indicator. Current is not
directly proportional to input power because power factor varies with
load and voltage.

Who should Help in promoting Eff1 Motors?

Finance Help
Are there any financing or leasing schemes for EE
Motors?

Yes, IREDA and other financial companies such as
ICICI, IDBI etc. have schemes that can help you to
acquire EE motors. (courtesy – web site of COPPER
– international copper Promotion council India)

Energy Efficient Motors & Carbon Credits
 Lower energy consumption means lesser burning of natural
resources – Thus lower pollution.
 Better efficiency means lower operating costs, hence improved
bottom lines.
 Opportunity to participate in World Carbon Credit Market, which
stands for just 6% in India (against 71% in China) at an estimated
value of US $ 64 billion as per World Bank Estimate for 2007.
(Source – Economic Times)

•Bharat Bijlee manufactures Energy Efficient motors
conforming to eff1 or eff2 of IS 12615
•Bharat Bijlee’s Standard Ex stock Motors conform to eff2 of
IS 12615
•Inferior motors conforming to IS 8789 are not manufactured
by Bharat Bijlee

Summary & Conclusion
 There exists a national standard IS 12615: 2004 (Revision 1) for energy
efficient three phase induction motors from 0.37kW to 160 kW
 Energy savings are more at partial loads because Energy Efficient
motors have a Flat Efficiency Vs. Load Characteristic
 Payback period of eff2 motor over IS-8789 motor is approx 1500 working
hrs.
 Payback period of eff1 motor over eff2 motor is approx 2500 working hrs.