1. By J P PATEL
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2.  OBJECTIVE of this program is to
understand how the energy is used in
industries and what is the opportunities
for energy conservations in industries.
 We will focus on energy conservation
opportunities and other ways to reduce
energy consumptions in industries and
buildings .
 These training provide a source for quick
savings energy in short time.
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3. Energy audit
An evaluation of energy consumption, in a
business, to determine ways in
which energy can be conserved. Measure
energy performance at a particular time
Three levels of audits carried out walk through,
preliminary and detailed
This does not talk about policy objectives etc
This is purely technical measurement of energy
and it its analysis over a period
Energy audit is an input to energy review
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4. 1. Boiler, & Steam System – Thermal
2. Furnaces and hot oil heaters – Thermal
3. Compressed Air System – Electrical
4. HVAC and Chillers- Electrical
5. Pumping System – Electrical
6. Blowers & Fans - Electrical
7. Electric Motors – Electrical
8. Gen-Set – Thermal
9. Lighting – Electrical
10.Heat Exchangers – Thermal
11.Cooling Towers/Evaporative Cooling- Thermal
& electrical
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5.  The boiler and steam system are important
equipment which has a significant impact on
energy.
 The main component of the boiler and steam
systems
 Burner (oil, gas, soil fuels like coal, biomass
etc)
 Water treatment systems
 Boiler components like fire tube or water
tube. Burner Deaerators, super heaters,
economizer, Airpreheater flue gas stack etc
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6. • The steam system components are:
Steam pressure reducing stations, steam pipe
insulations, steam trap system, condensate
piping.
• The major losses in boiler are:
1. Flue gas loss. (combustion loss)
2. Heat transfer surface not clean.-scaling of
tubes .
3. The combustion is not proper .
4. Formation of CO Radiation losses from boiler
body.- inadequate insulation
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7.  Poor combustion formation of CO and soot
(carbon)
 Heat transfer surface fouling
 Poor operating and maintenance
 Deteriorating fuel and water quality
 High flue gas temp. & more than required
excess air.
 Heat balance: identify heat losses
 Boiler efficiency: determine deviation from best
efficiency
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8. • The major losses in the steam system are:
1. The steam velocity(friction losses)
2. The dryness fraction of the steam(effective
working of the steam trap)
3. Saturated and condensing steam for heat
transfer purpose
4. Steam leakage through pipes
5. Insulation value, thickness
6. These are to be controlled and audited regularly
7. Rain water ingress in insulation, the insulation
looses its effectiveness .
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9. 1. Pipes –Optimum size, too high or too low size
means energy loss .
2. Drain points – Leaking points .
3. Strainers & Filters – Chocked strainers loss of
energy
4. Separators – to separate condensate from steam
5. Steam traps – leaking and improper
6. Air vents – leakage, poor venting of air .
7. Condensate recovery system – efficient system
saves both water and energy.
8. Insulation – Optimum level of insulation .
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10. 1. Stack temperature control
2. Feed water preheating using economizers
3. Combustion air pre-heating
4. Incomplete combustion minimization
5. Excess air control ( 5% for gas , 10% for
liquid fuels and 15 to 20% for solid fuels ) .
Can be achieved on online oxygen analysis
with controller on air to burner .
6. Avoid radiation and convection heat loss
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11. 7. Automatic blow down control
8. Reduction of scaling and soot losses
9. Reduction of boiler steam pressure
10.Variable speed control for boiler feed water
pump.
11.Controlling boiler loading
12.Proper boiler scheduling for batch process
requirements .
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12.  Steam should be available:
 In correct quantity
 At correct temperature –NO superheated
steam for heat transfer through condensation
 Free from air and incondensable gases
 Clean (no scale/dirt)
 Dryness fraction should be > 95%
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13. Compressor is one the major energy consuming
equipment and it is very important to control the
same.
Compressed Air is costliest form of energy.
• Compressed air system consists
 Air compressor
 Piping and valves
• The compressors main types
1. Reciprocating type ( least efficient )
2. Screw type
3. Centrifugal type ( most efficient )
The efficiency of each type varies and also
capacity limitations(for centrifugal)
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14.  To improve the efficiency select screw type
compressor for small medium applications.
 For large application select centrifugal type
which is the most efficient.
 However due the fact that cost of application
point of view the compressor selected.
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15.  The efficient use of the compressor depends
on how efficiently compressed air is used.
 In order to select right compressor use
dedicated compressor for different pressure
rather than throttling and reducing the
pressure(losses of energy).
• The other losses are from piping system are
two types:
1. Frictional losses
2. Leakages
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16.  The other possible saving can be replacing
the air operated valves with electrical
operated.
 Dirty filter(clean filter regularly).
 Loading-unloading cycles to be adjusted
carefully.
 Reduction in discharge pressure of
compressor
 Take a leakage test of compressed air system
and reduce the leakages. (Air leakage is a
waste of energy which is invisible)
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17.  Ensure air intake to compressor is not warm and
humid by locating compressor in well-ventilated
area.
 Minimize low-load compressor operation.
 Periodic cleaning of inter-coolers must be
ensured.
 Compressor free air delivery(FAD) test to check
the present operating capacity/design
 Use multi-stage compressor as it consumes less
power for the same air output than a single
stage compressor.
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18.  Keep the minimum possible range between load
and unload pressure settings.
 Reduce compressor delivery pressure, wherever
possible, to save energy.
 Carry out periodic leak tests to estimate the
quantity of leakage of compressed air.
 Install equipment interlocked solenoid cut-off
valves in the air system so that air supply to a
machine can be switched off when not in use.
 Check air compressor logs regularly for
abnormal readings.
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19.  HVAC is heating ventilation and air
conditioning.
 Ventilation system are used for fresh air
circulation.
 Air conditioning systems are used mainly as
comfort purpose to cool the air .
 Chillers are used for process cooling/chilling.
 The ventilation systems is mainly fans and
ducting.
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20. • Air conditioning systems are many types:
 Window
 Window split
 Packaged type
 Central air condition
The window and split AC are individual control.
The energy savings is mainly through
setting of temperature. However if it is used
for the process such as PLC control etc. The
requirement may be different
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21. • The central air condition systems are 2 types:
1.Direct expansion compressed
2.Chilled water system(by generating chilled
water and indirect cooling)
 The energy saving is achieved by selecting the
right type of compressor and controlling the air
handling units(ducting and blowers)
 The temperature control can be achieved by
sensors and thermostats
 The energy saving can be achieved by higher
setting of temperature and preventing leakage
of cool air. Better insulation also helps to save
energy on air conditioning.
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22.  Use water-cooled chillers rather than air-
cooled chiller.
 Avoid over sizing- match the connected load.
 Optimize condenser water flow rate and
refrigerated water flow rate.
 Improve control and utilization of outside air.
 Clean HVAC filters, unit coils on a schedule.
 Seal leaky HVAC ductwork and leaks around
coils.
 Establish an HVAC efficiency-maintenance
program for better efficiency.
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23.  Pumps are used for transferring fluids like
water, liquids etc from lower to higher level
called Head.
 Various types of pumps used like centrifugal,
reciprocating, rotary etc. are use
 The majority of pumps are centrifugal and
focus may on the centrifugal.
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24.  The system consist of pumps and piping and
valves.
 Like all fluid handling system the throttling of
pumps to be avoided as far as possible. The
throttling action gives lot of pressure drop
and hence the power.
 Also piping systems involves lot of friction
loss.
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25.  Pump shaft power (Ps) is actual horsepower
delivered to the pump shaft:
Pump shaft power (Ps)= Hydraulic power HP/
pump
efficiency
Pump efficiency = Hydraulic power/pump shaft
power
Pump output/Hydraulic/Water horsepower is
the liquid horse power delivered by the
pump.
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26. 1. Selecting the right pump
2. Controlling the flow rate by speed variation
(VFD)
3. Pumps in parallel to meet varying demand
4. Eliminating flow control valve
5. Eliminating by-pass control
6. Start/stop control of pump
7. Impeller trimming
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27.  Blowers and fans are similar to pumps but
handles compressible fluid such air.
• Fans and blowers are two type mainly used
1. Centrifugal
2. Axial
 The power consumption and characteristic
curves given by the supplier.
 Select the performance at the best efficiency
point
 Estimate correct pressure drop across the system
 It is always better to modify the ducting system
rather than throttling.
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28.  Sum of static pressure losses in system:
1.Configuration of ducts, pickups, elbows
2.Pressure drop across equipment
• Increases with square of air volume
 Long narrow ducts, many bends: more
resistance
 Large ducts, few bends: less resistance
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29. 1. Choose the right fan
2. Reduce the system resistance
3. Operate close to BEP (best efficiency point)
4. Maintain fans regularly
5. Control the fan air flow
 Properly lubricated precision spur gears 98% for
each step
 Flat belt drive 97% - Power transmission loss 3%
 V-belt drive 95% Transmission loss is 5%
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30.  Motors are the prime movers in many
industries.
 Motors are used to run the machinery and
other systems like water pumping, air moving
in fans, blowers and compressors.
 The major consumption of electric power is
the motors in many industries.
 Therefore more attention may be given to the
motors and its efficient use.
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31.  In general motors are classified with their
efficiency like high efficient motors.
 The motors of NEMA standards are the highest
efficiency. (90% and above)
 The motor efficiency depend on the load of the
motors(less than 50% load is highly inefficient).
Motor manufacturers give efficiency at full
load.
 Rewind motors looses the efficiency due to
poor winding and the winding losses are more
. Motor efficiency goes down by 1 to 1.5%.
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32.  The motors are fitted to machines through
various transmission devices.
 These are direct mounting on the motor shaft
through coupling. The transmission losses is
around 5%.
 Through belts and pulleys properly
maintained and the selection belts can save
up to 3% of power.
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33.  The electrical systems consist of incoming
transformers, bus bars, cabling and internal
distribution through MCC’s.
 The power may be obtained from grid or by
Diesel gen-set or by both.
 The energy saving is by maintenance of
power factor(Lagging).
 The power can be saved by selecting right
size cables which can minimize the I2 R
losses. Proper cable connection can also
reduce the loss.
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34.  Lighting account for 5-10% of the electrical
energy consumed in the industries and 30 to
40 % in commercial buildings and malls .
 The lighting system are used for general
lighting.
 Task lighting
 Street and security lighting
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35. • The lights are many types:
 Incandescent – Highly inefficient
 Fluorescent – tubes T-10 & T-12 , & T-5
 Compact fluorescent(CFL)
 Metal halide
 Halogen
 Mercury vapor
 High pressure sodium vapor
 LED
 Induction
LED and T-5 are most energy efficient and
long lasting .
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36. • The energy conservation methods
 Use dimmer wherever possible
 Change the chokes magnetic (15 w) to
electronic chokes (1w)
 Replace T8 tube with T5 or with LED
 Replace CFL with LED .
 Use of Natural lights by transparent plastic
roof sheets
 LED and Induction light can be considered after
all above modification
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37.  Energy performance indicators ENPI
 It is defined as ratio energy consumed over a
defined period to the output or as defined by
the company
 Base lines are the bench mark derived from
statistical method either average or regression
or by cusum methods.
 The base lines are adjusted as per the changes
ENPI due the variable such as operating
condition
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38.  Electrical measuring instruments- power
analyzer.
 Combustion analyzer
 Manometers
 Thermometers – infra red (Non Contact Type)
 Water flow meters – Ultrasonic flow meter
 Speed measurement –Tacho meters
 Leak detectors
 Lux meters – for light intensity measurement.
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39.  Lighting – LED and Induction lighting
 Solar Thermal- like vacuum evacuated tube,
Fresnel collectors for higher temperature.
 Absorption chillers
 Heat of compression drying(air compressors)
 Dry type transformers
 Biogas from sewage and bio-waste
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41.  Heat exchangers performance measurement
 Tube cleaning periodically based on
performance
 Use of heat exchanger as Economiser by
pinch technology
 Less opportunities for energy saving as
compared to other machineries.
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43.  Cooling tower fans made of FRP blades are
aerodynamic in profile to meet specific duty
conditions more efficiently.
 Due to light weight FRP fans need low
starting torque resulting in use of lower HP
motors.
 Proper gas liquid contact leads to better mass
transfer/Evaporative cooling
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44. Implementation
energy conservations and also
efficiency of the equipment is necessary.
Therefore the organization can think of
 performing energy audit
 EnMS system implementation will lead to
excellence in energy saving and
sustainability.
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