Energy

conservation
measures
in the fruit
and vegetable
processing
sector

Energy-Efficiency booklet-NEW.p65 1 23/09/2008, 2:59 PM

 DFID
The Department for International Development (DFID) is the British government department responsible
for Britain’s contribution towards international efforts to eliminate poverty. DFID works in partnership
with developing country governments towards poverty alleviation. DFID supports long-term
programmes to help tackle the underlying causes of poverty. DFID recognises that the development
of micro small and medium enterprises (MSMEs) is key to creating the jobs and income needed to
reduce India’s poverty. DFID is supporting the development of the MSME sector in India through
MSME Financing & Development project (SMEFDP) being implemented by SIDBI. SMEFDP aims
to enhance MSMEs’ access to institutional finance and to market oriented Business Development
Services. The Technical Assistance part of the project is funded by DFID.

TERI
TERI (The Energy and Resources Institute), a dynamic and flexible organization with a global
vision and a local focus, was established in 1974. A unique developing-country institution, TERI is
deeply committed to every aspect of sustainable development. From providing environment-friendly
solutions to rural energy requirements to helping shape the development of the Indian oil and gas
sector; from tackling global climate change issues across continents to helping conserve forests;
from advancing solutions to the growing urban transport and air pollution to promoting energy
efficiency in the Indian industry, the emphasis has always been on finding innovative solutions to
make the world a better place to live in. To this end, TERI has established regional centres in
Bangalore (Karnataka), Panaji (Goa), Guwahati (Assam), Supi (Uttarakhand) and Mumbai
(Maharashtra). It has set up affiliate institutes: TERI–NA (The Energy and Resources Institute, North
America) in Washington, DC, USA and TERI–Europe, London, UK; and it also has a presence in
Japan, Malaysia, the UAE, and Africa.

Disclaimer
This document is an initiative of Small Industries Development Bank of India (SIDBI) for the benefit of MSME units. While every effort
has been made to avoid any mistakes or omissions, SIDBI would not be in any way liable to any person by reason of any mistake/
omission in the publication. The graphs, tables and other analyses of data that are carried in various part of this publication have been
drawn from variety of resources, both primary and secondary. It has not been possible to acknowledge individually the various
contributions. However, TERI acknowledges with gratitude the contributions made by various researchers/organizations who have
provided these data.

Published by
T E R I Press, The Energy and Resources Institute, Darbari Seth Block, IHC Complex, Lodhi Road,
New Delhi – 110 003. INDIA

2 Energy conservation measures in the fruit and vegetable processing sector

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 Preface
Micro, small and medium enterprises or MSMEs play a vital role in the Indian economy.
The manufacture of a vast range of products takes place in these units. In addition,
this sector mobilizes local capital and skills, provides jobs to millions of people, and
thereby provides the impetus for growth and development, particularly in rural areas
and small towns.

In today’s liberalized economy, MSMEs have to face competition not only from medium
and large enterprises in India, but also from imports often manufactured in large scale industries using modern
technology and equipment. The survival and growth of MSMEs therefore hinges on their ability to remain
competitive: that is, to improve productivity and quality of products, and to develop new products for keeping up
with changing demands. Of the estimated 400 energy-intensive MSME clusters in the country, most comprise
units that operate on obsolete or inefficient technologies. This leads to wastage of energy as well as considerable
emissions of greenhouse gases. To compound the problem, these units often do not have either the technical
capacity or the resources to modify/change their inefficient technologies.

The National Action Plan on Climate Change, released by the Prime Minister of India on 30th June 2008,
acknowledges the need for external support to promote energy efficiency for small-scale industries. The NAPCC
states that ‘The information or knowledge gap is more pronounced in case of small industries and “hand-holding”
to help industries install energy efficient technologies as well as to ensure their optimum performance through
best operating practices will be required’. These in turn can bring down the overall emission levels of units, and
thereby reduce their environmental impact at both local and global levels.

An example is the fruit and vegetable processing cluster located in Pune, Maharashtra. Energy is a key input in
food processing; yet a majority of units use energy inefficiently in their operations. SIDBI (Small Industries
Development Bank of India) recognized both the need and the potential for saving energy in this important MSME
cluster. In a project commissioned by SIDBI, TERI studied the energy consumption patterns of representative
units in the cluster, and identified areas in which low-cost measures could be undertaken to save energy.

This booklet is an outcome of the project. It contains simple but invaluable tips for units to improve their energy
performance, and thereby improve the profitability of their operations as well as reduce their environmental
impacts. There is a good possibility of extending the initiative by not only providing technical back-up support to
interested entrepreneurs in the Pune cluster to adopt some of these measures and also to extend the programme
to other energy-intensive small-scale clusters in India. TERI’s decade long experience of working in the Firozabad
glass industry cluster and the Rajkot foundry cluster clearly shows that investments in technology development,
demonstration and capacity building at local levels are key ingredients for developing long-term successful initiatives
in the MSME sector.

R K Pachauri
Director-General, TERI

Energy conservation measures in the fruit and vegetable processing sector 3

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 4 Energy conservation measures in the fruit and vegetable processing sector

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 Energy conservation measures in the fruit and vegetable processing sector 5

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 Foreword
The MSME sector has played a very important role in the socio-economic development
of the country during the past 50 years. It has significantly contributed to the overall
growth in terms of the Gross Domestic Product (GDP), employment generation and
exports. The performance of the sector, therefore, has a direct impact on the growth
of the overall economy. SIDBI is proud to be associated with the promotion &
development of this vibrant sector.

SIDBI is implementing a multi agency / multi activity Project on Financing and

Development of Micro, Small & Medium Scale Enterprises. The Project is aimed at making lending to the sector,
an attractive and viable financing option as also facilitating increased turnover and employment in the sector.
The project has 3 major Components viz. Credit facility from the World Bank (WB) and KfW , Risk Sharing Facility,
and Technical Assistance (TA) from Department for International Development (DFID). A dedicated Project
Management Division (PMD) has been setup by SIDBI to implement this project.

"Business Development Services" (BDS) in MSME Clusters is the cornerstone of the DFID TA. BDS refers to the
wide range of services used by entrepreneurs to help them operate efficiently and grow their businesses. SIDBI
has started the BDS interventions in 3 clusters namely Alleppey (Coir), Kanpur (Leather) & Pune (Fruit & Vegetable
processing).

The Fruit &Vegetable processing cluster uses a substantial amount of energy in the manufacturing process. It
has been found that the profitability of the MSME units can be improved through simple energy saving initiatives
/ house-keeping measures. However, most of the MSME units do not have ready access to these measures and
thus there is a need to raise the level of awareness on the simple, cost-effective solutions that would reduce the
energy consumption of this sector and improve its competitiveness. PMD, SIDBI has therefore commissioned
The Energy and Resources Institute (TERI) to undertake a study of the cluster and prepare a simple Do's and
Don'ts booklet for the purpose.

The booklet prepared by TERI offers simple & useful tips on saving energy. It is expected that this booklet would
be helpful not only to the Fruit & Vegetable Processing sector in Pune but also to many such units all over the
country.

R M Malla
Chairman and Managing Director
SIDBI

6 Energy conservation measures in the fruit and vegetable processing sector

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 Introduction Excess air and flue gas temperature are two
important parameters on which the boiler
The cost of energy is a significant controllable factor in efficiency depends
the food-processing sector. Typically, it depends on the
processes and the product types, and accounts for up to A 22 °C reduction in the flue gas temperature
10%–15% of the production cost. Significant saving can reduces the fuel consumption by 1%
be made in the energy bill by implementing simple energy Every 6 °C rise in feed water temperature by
conservation measures outlined in this booklet. heat recovery or condensate recovery
High energy-consuming areas in various types corresponds to a 1% saving in fuel
of food-processing industries are highlighted in the consumption in the boiler
table below.

Type of products Critical areas P Provide gauges for steam pressure and
temperature on boilers and temperature gauge in
Frozen fruits and Boiler, refrigeration, cold
the flue gas outlet and monitor the data regularly.
vegetables storage, blast freezing,
P Analyse flue gas regularly by using portable flue
motors, cooling tower
gas analyser. The parameters to be checked are
Tomato ketchup/puree/ Boiler, steam heating, steam O 2 (oxygen), CO (carbon monoxide), and
juice, sauces, canned traps, motors temperature.
fruits and vegetables, P Optimize excess air in the boiler. Excess air is the
fruit pulps, juices
quantity of air in addition to the theoretical
Ready-to-cook, ready-to- Grinder and pulverizer, quantity required for 100% fuel combustion.
eat, instant mixes, soup motors, air compressor, Recommended excess air and O2 levels for various
mixes and pickle, spices, lighting fuels are mentioned in Table 1.
chutneys P Observe colour of the smoke coming out of the
Candies and jellies Boiler, steam usage, motors boiler. Brown hazy smoke indicates proper
combustion; black colour indicates incomplete
combustion; and colourless or white smoke shows
Steam generation and high excess air quantity as shown in Figure 1.
P 5 % reduction in excess air quantity (above the
distribution system recommended excess air percentage) increases the
boiler efficiency by 1%. Similarly, 1% reduction
Steam – in the fruit and vegetable, and food processing
of residual oxygen in the flue gas reduces fuel
industry – is generally used for blanching, peeling, heat
consumption by 1%.
sterilization, evaporation, pasteurization, hot water
generation, indirect heating, and so on. Energy can be
saved both in steam generation and distribution through Table 1 Recommended O2 and excess air levels
some simple measures as mentioned below.
P Adopt biomass-based boiler, wherever possible. Recommended O2 Excess air
It is environment friendly and does not contribute to Fuel level in flue gas (%) (%)
GHG (greenhouse gas) emissions.
Diesel 2–3 10–15
P Arrest fuel oil leakage. Even a small oil leakage
Bagasse 5–7 25–35
of one drop per second can result in wastage of 4000
Wood/biomass 4–5 20–25
litres per year of fuel oil.

Energy conservation measures in the fruit and vegetable processing sector 7

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 of a bare 2-inch pipe carrying saturated steam at
10 kg/cm2 is equivalent to a fuel loss of about
1100 litres of fuel oil per month.
P Insulate all flanges by using pre-moulded sections
because heat loss from a pair of bare flanges is
equivalent to the loss from 1 foot of non-insulated
pipe of same diameter.
P Use air vents to remove the trapped air from the
jacketed vessel as air acts as insulator and
reduces the heat transfer. A 0.25-mm thick air
film offers the same resistance to heat transfer
Figure 1 Colour of smoke from boiler chimney as a 330-mm thick copper wall.
P Recover the sensible heat from the hot flue gas P For all indirect steam heating, use steam at a
for heating the boiler water (via economizer) or lowest acceptable pressure, since the latent heat
preheating the combustion air (via air-preheater). of steam at lower pressure is higher.
P The boiler tubes should be cleaned regularly to P Fix all steam leakages as soon as they are
avoid deposition of scale. A 1-mm thick scale identified. A 3-mm diameter hole on a pipeline
(deposit) on the water side of boiler tubes could carrying steam at 7 kg/cm2 would waste 33 000
increase fuel consumption by 5%–8%. litres of fuel oil per year. Figure 2 shows the steam
P The boiler should be checked for any soot and fly wastages from various leakage sizes at different
ash deposition on the fire side of boiler tubes. pressures.
If the flue gas temperature rises about 40 °C P Install temperature gauges in all steam heating
above the design specification, it is time to remove equipment and avoid overheating of material.
the soot deposits. A 3-mm thick soot deposition
on the heat transfer surface can increase the fuel
consumption by 2.5%.
P Recover and return condensate to the boiler, as it
still carries about 15%–20% of the total steam
energy.
P Insulate all steam/condensate pipes, condensate/
hot water tanks with proper insulation as
indicated in Table 2. The heat loss from 100 feet

Table 2 Indicative thickness (in mm) for mineral

wool insulation for various steam pipe sizes

Temperature 1-inch 2-inch 4-inch

(ºC) diameter diameter diameter

Up to 100 25 40 65
100–150 40 50 75
150–200 50 65 100
200–250 65 75 125 Figure 2 Indicative steam losses from various
leakage sizes and pressure

8 Energy conservation measures in the fruit and vegetable processing sector

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 P Keep the steam trap bypass line closed always
except during start up. If the trap is faulty, replace Since the efficiency of the compressed air system,
the trap rather than opening the bypass valve. from generation to end-use, is less than 10%
P Make use of Table 3 for efficient steam trap (Figure 3), it must be used judicially in the plant
management in the plant. All compressed air usage for cleaning the
floor/equipment/personal cleaning must be
Compressed air system avoided. Air blowers are well suited for
such applications as they generate large
Compressed air is generally used in all food processing volume of air at lower pressure with lower
industry for machine operations, pneumatic controls, energy consumption
and other similar applications. Following
recommendations should be followed for an efficient Every 5 °C rise in suction air temperature will
compressed air system. increase power consumption by 2%
P The air intake to the compressor should be clean,
cool (certainly not from the air-conditioned area) P Compressor discharge pressure should be kept at
and drawn from a place, which is away from the minimum acceptable level. Increase of 1 kg/cm2 air
heat sources. discharge pressure (above the desired) from the

Table 3 Tips for efficient use of steam traps

Wrong installation Description Correct installation

Steam traps should be fitted in the direction

of flow. All steam traps have the mark showing
the flow direction

Never use an inlet pipe smaller than the trap

size

Never install steam trap at a higher level

than the drainage point to avoid back
pressure

Condensate discharge from traps operating at

different pressures should not be collected
to a common collector

Each steam-using unit should always

have an individual steam trap

Condensate main should have a cross sectional

area more than the sum of all the traps connected
to it

Energy conservation measures in the fruit and vegetable processing sector 9

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 compressor would result in about 4%–5% increase in P Use a properly sized compressed air storage
input power. This will also increase compressed air receiver. It dampens the pulsation from the
leakage rates roughly by 10%. reciprocating compressor and makes the flow of
P If compressed air is required at two different air smooth. It also acts as a reservoir to meet short
pressures, it is better to have two compressors time excess demand in the system, condenses
catering to air requirement at different pressures moisture, and removes the oil traces (through drain
rather than having one large compressor generating trap) from the compressed air. The size of the
compressed air at higher pressure. receiver should be at least 6–10 seconds capacity
P Air intake filters should be cleaned at regular of the compressor. It is always beneficial to over
intervals to facilitate clean air intake of design the air receiver. The receiver should be fitted
compressor and low pressure drop across it. with a pressure gauge, safety valve, and a moisture
P Compressed air should be cooled up to the ambient drain valve.
temperature by using after coolers/air dryers before P Compressed air generation is a costly affair. Therefore,
it enters in the system. This will help in removing always debate the addition of a new compressed air
the moisture from the system. based application. Consider alternatives to
P Provide separators to get rid of any moisture in compressed air such as blowers for low-pressure high-
the system before the compressed air reaches the quantity applications, hydraulic rather than air
pneumatic equipment. cylinders, electric rather than air actuators, and
P Change the oil filter regularly. electronic rather than pneumatic controls.
P All the compressed air piping should be laid out in P It is very difficult to eliminate air leakages from a
such a way that it minimizes pressure drops during compressed air network. Although, large leakages are
transmission. The pressure drops in a smaller identified by their sound, small leakages generally go
compressed air system should not be more than unnoticed. Leakages can be identified by their hissing
0.3 bar. sound, during the non-operational time. Air leakages
depend on the air pressure and the size. Leakages
through various orifice sizes (at 7 kg/cm 2) are
mentioned in Table 4. Common sources of leakages
are coupling, hoses, fittings, pressure regulators,
valves, pipe joints, and drain traps.

Table 4 Power wasted due to air leakages

Orifice size Air leakage Power wasted

(inch) (Nm3/hour) (kW)

1/32 2.9 0.3

1/16 11.5 1.3
1/8 46.2 5.0
1/4 184.8 20.2

Figure 3 Typical sankey diagram for a compressed air

system

10 Energy conservation measures in the fruit and vegetable processing sector

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 Electrical distribution system
Electrical system is an integral part of all food processing
industry. An efficient electrical distribution system and
demand management can reduce the electricity bill
significantly. Box 3 shows a typical electricity bill along
with possible areas of energy savings. This section
provides some of the opportunities to improve efficiency
of the distribution network.
P Stagger the non-critical load according to the
electricity tariff to reduce your bill. The benefit due
to this is shown in Box 1.
P The benefits of higher power factor are reduced
demand (as shown in the Box 2), better voltage,
high system efficiency and rebate from the
electricity supplying company. Power factor can Maximum efficiency of a transformer is at
be improved by installing capacitors in the 32% –35% load of its full load capacity
electrical system. Table 5 provides the values of
capacitance required per unit kilowatt, to improve Maintain the power factor at the main feeder
power factor from 0.85 to a desired level up to 1. greater than 0.9 to avoid penalty and further
P Provide capacitor at the load (motor) end to have improve it to above 0.95 to avail the rebate
the benefit of reduced distribution loss (for
example, line losses, and cable loading). Any Control the maximum demand by tripping the
shortfall from the desired power factor can be non-critical loads through a demand controller.
met by connecting the capacitors at the main This will avoid the penalty due to excess
panel. It should always be less or equal to unity demand usage than the sanctioned
and never be leading, which may lead to motor

Box 1 Benefits of load staggering Box 2 Savings in demand due to high power
Load to be shifted to night shift (10 p.m.—6 a.m.) = 10 kW factor
from the general shift (9 a.m.–5:30 p.m.)
Existing load of the unit (kW) = 100
Assumed working hours per shift =6 Existing power factor = 0.90
Monthly power consumption (kWh) = 1200 Existing maximum demand of the unit (kVA) = 111
(Assuming 20 days operation per month) Desired power factor = 0.98
Electrical cost for night shift operation (Rs) = 3600 Capacitor required (kVAR) = ~30
New demand of the unit (kVA) = 102
(@ Rs 3/kWh during 10 p.m.—6 a.m.)
Reduction in maximum demand (kVA) (Rs) = 9
Electrical cost for general shift operation (Rs) = 5100
Monthly savings in demand charges@ Rs 300/kVA(Rs) = 2700
(@ Rs 4.65/kWh during 9 a.m.—12 p.m. and Savings per annum (Rs) = 32 400
@ Rs 3.85/kWh during 12 p.m.–6 p.m.) Cost of capacitors @ Rs 250/kVAR (Rs) = 7 500
Savings per months (Rs) = 1500 Simple payback period = less than
3 months
Annual savings (Rs) = 18 000

Energy conservation measures in the fruit and vegetable processing sector 11

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 Box 3 Typical electricity bill showing some possible areas of savings

12 Energy conservation measures in the fruit and vegetable processing sector

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 Table 5 Multipliers to determine capacitor kVAR required for power factor correction
Original Desired Power Factor
Power
Factor 0.85 0.86 0.87 0.88 0.89 0.90 0.91 0.92 0.93 0.94 0.95 0.96 0.97 0.98 0.99 1.0

0.85 0.00 0.03 0.05 0.08 0.11 0.14 0.16 0.19 0.23 0.26 0.29 0.33 0.37 0.42 0.48 0.62
0.86 0.00 0.26 0.53 0.08 0.11 0.14 0.17 0.20 0.23 0.26 0.30 0.34 0.39 0.45 0.59
0.87 0.00 0.03 0.06 0.08 0.11 0.14 0.17 0.20 0.24 0.28 0.32 0.36 0.42 0.57
0.88 0.00 0.03 0.06 0.08 0.11 0.15 0.18 0.21 0.25 0.29 0.34 0.40 0.54
0.89 0.00 0.03 0.06 0.09 0.12 0.15 0.18 0.22 0.26 0.31 0.37 0.51
0.90 0.00 0.03 0.06 0.09 0.12 0.16 0.19 0.23 0.28 0.34 0.48
0.91 0.00 0.03 0.06 0.09 0.13 0.16 0.21 0.25 0.31 0.46
0.92 0.00 0.03 0.06 0.10 0.13 0.18 0.22 0.28 0.43
0.93 0.00 0.03 0.07 0.10 0.14 0.19 0.25 0.40
0.94 0.00 0.03 0.07 0.11 0.16 0.22 0.36
0.95 0.00 0.04 0.08 0.13 0.19 0.33
0.96 0.00 0.04 0.09 0.15 0.29
0.97 0.00 0.05 0.11 0.25
0.98 0.00 0.06 0.20
0.99 0.00 0.14
0.00

Required capacitor rating (kVAR)= Load (kW) × multiplication factor

burning. Use automatic power factor relay for Develop the habit of switching off the lights
effective power factor management. whenever not required
P Transformers are, normally, designed to operate Clean the lamp and fixture regularly for better
at maximum efficiency between loadings of 32% lighting efficiency
and 35% of its full load capacity. If the load on Immediately replace the fused tube light to
transformer increases beyond 80% of the avoid choke losses in tube light fitting
designed capacity, it is better to go for a new or without any useful lighting
bigger transformer to avoid the sharp rise in
transformer losses.
Box 4 Replacement of incandescent lamp (100 W) with CFL
Lighting Lamp wattage = 100
Wattage of CFL (for equivalent lighting)(W) = 23
Energy savings in lighting can be realized by adopting Savings in lighting load per lamp (W) = 77
the following tips. Annual energy savings (kWh) = 138
P Make the maximum use of daylight by providing (Based on 6 hours/day for 300 days)
translucent roof sheets, glass window, etc., as it Monetary savings (rupees) = 690
is freely available. (@average of Rs 5/kWh, inclusive of all charges)
Cost of CFL (rupees) = 160
P Replace all the incandescent bulbs with CFL
Simple payback period (years) = 0.2
(compact fluorescent lamp). A case study for such
replacement is shown in Box 4. This calculation doesn’t include the savings due to reduction
in demand.

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 P Replace all 40 W conventional tube lights with as ventilation fans, compressors, and pumps) equipment.
more efficient T5 lights (28 W). A case study for Some energy conservation opportunities for small food
this is mentioned in Box 5. processing units are given below.
P Replacement of mercury vapour lamps with P Always use properly sized motors as per the load
70 W low pressure sodium vapour (LPSV) lamp, application. Oversized motors can result in
for street lighting or the area where colour unnecessary energy wastage due to decrease in
rendering is not important, will result in 40%– efficiency and power factor (Figure 4). A case study
50% electricity savings. is shown in Box 6.
P Consider painting the inner walls with a lighter
colour. This will require less number of lighting
fixtures.

Box 5 Replacement of conventional tube light with energy-

efficient 28 W T5 lighting system

Wattage of lamp and ballast (40+15) = 55

Wattage of T-5 Lamp and ballast (28+2) = 30
Reduction in wattage = 25
Total Reduction in kW = .025
Annual electricity saving in kWh = 60
(Based on 8 hours/day for 300 days)
Annual monetary savings (rupees) = 300
(@average of Rs 5/kWh, inclusive of all charges)
Cost of T5 lighting system (rupees) = 800 Figure 4 Variation in efficiency and power factor
Simple payback period in years = 2.7 with load for a typical motor
This calculation doesn’t include the savings due to reduction in
demand.
Box 6 Replacement of an oversized motor with
an appropriate one
Motors Parameters Existing Proposed
case case
Motors are used throughout a typical food-processing unit
for various processes (such as mixing, grinding, peeling, Rating (kW) 15 11
cutting, pulping, filling, and packaging) and utility (such Shaft load (kW) 8.3 8.3
Percentage loading on the motor 55.3 75.5
A 20% reduction in motor speed will result Power factor 0.75 0.88
into almost 50% power savings Motor efficiency (%) 84 86
Motor input power (kW) 9.88 9.65
All new replacements should be done with Reduction in input power (kW) – 0.23
energy-efficient motors having 3%–5% higher Working hours per year 6000 6000
efficiency Annual electricity savings (kWh) – 1380
Monetary savings (rupees) – 6900
It is better to replace the old motor which has
(@ Rs 5/kWh)
undergone rewinding 3 times. Motor efficiency Cost of new motors (rupees) – 20 000
goes down by 3% – 5% after each rewinding Simple pay back period (years) – 2.9

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 P The motor should be rewound by a qualified person.
This will minimize the losses in the rewound motor. Condenser coils should regularly be cleaned.
P If a motor is continuously running below 45% A scale build-up of 1 mm on condenser tubes can
of its design load, it is better to operate it in star increase energy consumption by 40%
mode by changing to star connection or by All the lights in the cold storage/refrigeration
installing auto delta-star converter. This will give chamber should be kept off, if there is no
a handsome saving. movement, to avoid unnecessary heat load. Heat
P It is appropriate to use VSD (variable speed drive) due to lighting can add up to 5%–10% of the
with the motor, if the load is of variable nature refrigeration load
such as that for pumps, fans, and mixers. VSD
Always examine new low-temperature cooling
matches the motor speed as per the load and
requirements and the temperature required to be
results in savings.
attained by the product. Additional cooling by
every 1 °C will increase the compressor power
Refrigeration system consumption by 3%–5%
Refrigeration systems consume a significant amount
of electricity in the frozen fruits and vegetable-
processing units. These are required for generating P All different cooling applications should be
chilled water for various cooling applications and also segregated. A chiller compressor catering to low-
to generate cold air for cold storage, and freezing of temperature application (that is, freezing or cold
fruits and vegetables. The following suggestions will storage) must not be used for generating chilled
help in reducing the energy bill and also in improving water for cooling purposes.
the performance of refrigeration system. P It is important to keep the surfaces of condenser
P Maintain the suction and discharge parameters and evaporator clean for better heat transfer.
of the refrigerant as recommended by the Fouling or deposits on condensing/evaporating
manufacturer for efficient chilling/refrigeration coils can lead to high condenser gas pressure and
operation. temperature, and low evaporation temperature and
P Switch off the chiller compressor as soon as the pressure. In both the cases, compressor power
required temperature is achieved. It is better to consumption will increase.
automate the compressor controls to have P Plug the refrigerant leakages as soon as they are
superior matching of cooling/ refrigeration demand identified.
and compressor load. Use of VSD can further P Regularly check the pipe insulation. Any damage
reduce the energy consumption in a system having or removal should immediately be attended to.
variable cooling demand. P All the doors of cold storage/refrigeration chamber
should be tightly closed to avoid the infiltration
of outside air. They should not be opened too
frequently and the duration of opening should be
as short as possible. All unnecessary movement
in it should be curtailed to avoid heat ingress, even
from the human body. The energy loss due to
improper door management can be as high as
10%–20%.
P Remove all the excess surface water from the
fruit/vegetable/corn before refrigeration (blast

Energy conservation measures in the fruit and vegetable processing sector 15

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 freezing) as it will lead to extra energy
consumption by the refrigeration compressor. Box 7 Savings due to switching to ice formation
P For the chilled water requirement during the day, during night
it would be cheaper to operate chiller plant during
Chiller capacity (TR) = 15
the night, when the electricity charges are less,
Motor size (kW) = 15
and form ice in the tank. The ice can be used for
Load on motor (@80%) in kW = 12
generating chilled water during the day. For ice Power consumption (kWh) = 21 600
bank operation, insulation of the ice/chilled water (Assuming 6 hours/day and 300 days
tank has to be in good condition. A case study operation per year)
for such operation is mentioned in Box 7. Electrical cost for night shift operation (Rs) = 64 800
P Avoid frost formation on the evaporation coils in (@ Rs 3/kWh during 10 p.m.–6 a.m.)
the blast freezer and cold storage by regular Electrical cost for general shift operation (Rs) = 91 800
defrosting. Frost acts as an insulator and slows (@ Rs 4.65/kWh during 9 a.m.–12 p.m. and
down the heat transfer between the cooling air @ Rs 3.85/kWh during 12 p.m.–6 p.m.)
and coils thereby leading to the lower suction Savings per year (Rs) = 27 000
temperature at the compressor. A reduction in
refrigerant evaporation temperature by 1 °C will
increase the compressor power consumption by
about 3%. during night/colder months. This can be
automated by installing a basin water
temperature based controller for fan operation.
Cooling towers P Clean the distribution nozzles in the cooling tower
Cooling tower is a sub-system of a refrigeration system regularly to have uniform distribution of water.
and its performance can significantly affect the P Consider installation of energy-efficient FRP
performance of a refrigeration system. By following blades since they consume 15%–20% less energy
the measures given below, energy savings and better compared to cast iron/aluminium blades with the
cooling tower performance can be achieved. same airflow.
P Cooling towers are designed based on the worst P Avoid idle operation of cooling tower and
condition in the region. Therefore, control the circulation of cooling water to an application that
operation of the cooling tower fan based on is not operating.
leaving water temperatures. Switch off the P Avoid buying an oversized cooling tower.
cooling tower fan when loads are reduced or

Aerodynamic FRP (fibre reinforced plastic) fan

blades can reduce the fan energy consumption
by 15%–20% in cooling towers
Replace splash bars with PVC cellular-film fill
for efficient cooling tower operation

Keep water in the cooling tower basin free of

algal growth

16 Energy conservation measures in the fruit and vegetable processing sector

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 Diesel generating sets Process
DG sets in the food processing industry are generally Energy consumption in the processing of fruits and
used to provide back up power during power cuts or vegetables can also be reduced by inducting more
when there is no power. Adopting measures given efficient process equipment or by adopting the latest
below will keep the DG sets in good condition. technologies as mentioned below.
P The performance of the DG set can be evaluated P Whenever new process equipment is bought it
in terms of SEGR (specific energy generation ratio) should have better efficiency even if the cost is
in kWh/litre, which provides combined efficiency higher. The life cycle cost (purchase and operating
including the engine and alternator. cost) of a more efficient equipment is less
P Conduct regular SEGR trials to monitor the compared to one with lesser efficiency.
performance of DG sets. If the operating value of P All new steam using equipment (vats, blanchers,
SEGR is less than 80% of the design value, at indirect heaters, and so on ) should have proper
optimum load and with all other parameters within steam seals to stop steam leakage, proper
limit, it is time to contact the manufacturer for insulation to minimize heat loss through surface
overhauling. and process controller (with temperature
P Consider the use of fuel oil additives in the DG indicators) to regulate steam flow based on the
set after carefully evaluating the results. product.
P In case of a base load operation, explore the P Infrared heating could be a more efficient option.
possibility of waste heat recovery for hot water In conventional heating, substantial heat quantity
generation from the DG set’s exhaust. is used to heat the product and surroundings,
whereas in infrared drying, infrared radiation
heats only the material that needs to be heated—
The fuel consumption per unit of power not the surrounding air—and thus saves energy
generation is lowest if the DG set is loaded in a compared to conventional methods.
range of 60%–80% of the design capacity, P Solar energy is available in plenty and should be
without fluctuation explored for possible use in food industry. Sunlight
Air intake to the DG set should be cool and free in India varies from 2300 to 3200 hours per year,
from dust, preferably outside the generator room with an average radiation of 4–5 kWh/m2/day.
Solar collectors for applications using 90—95 oC
Clean the air filters regularly to reduce the temperature, namely flat plate and evacuated
pressure drop across it collectors, are readily available in India. This
temperature is enough to cater to many
applications such as hot water/air generation in
the food-processing cluster.
P Waste generated from the fruits and vegetables
based industry can be used for biogas generation,
which could be used for heat generation. The
biogas generated can be used in the boiler to
replace fossil fuel for example, LPG/oil. The
techno-economic feasibility of plants of various
capacities is given in Table 6.

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 Table 6 Techno-economic feasibility for installing a biogas generation plant

Quantity of the waste 100 kg/day 150 kg/day 250 kg/day

Quantity of the biogas to be generated (m3/day) 6 9 15

LPG equivalent (kg/day) 3 4.5 7.5
Savings due to replacement of LPG (Rs/day) (@ Rs 80/kg LPG) 240 360 600
Manure generation (kg/day) (@10% of the waste) 10 15 25
Savings due to manure (Rs/day) (@ Rs 3/kg) 30 45 75
Net revenue (Rs/day) 270 405 675
Net annual recovery (Rs/year) (@300 days operation per year) 81 000 121 500 202 500
Cost of plant (rupees) 430 000 450 000 480 000
Pay back period (year) 5.2 3.7 2.4

Conclusions P Optimize water usage and reduce water wastages

P Make maximum use of day-lighting by using
Energy is an important basic input in the manufacturing translucent sheets on roof and glass windows
process and its saving will have direct impact on the P Replace exhaust fans with air circulators wherever
profitability of the manufacturers. It is expected that by possible
implementing the suggestions mentioned in this booklet, P Avoid leakages of fuel oil
plants can save about 5%–10% of their energy costs. P Insulate the bare surfaces in the steam and chilled
Some general guidelines for energy water system
conservation, which are applicable to a wide spectrum P Avoid compressed air for floor/personal cleaning
of plants in Pune’s fruit and vegetable processing cluster, P Avoid power factor penalty by maintaining power
are summarized below. factor above 0.9
P Regularly undertake energy audit P Replace all fused tubes at the earliest to avoid choke
P Meter your energy consumption losses
P Optimize the equipment usage P Whenever buying a new motor always opt for high
P Switch off lights, motors, equipment, and so on when efficiency motors
not in use P Keep all lights off in cold storage to avoid additional
P Replace old/inefficient equipment with the new and load on refrigeration system due to extra heat load
more efficient ones of lighting fixture, if there is no movement

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 SOME GENERAL GUIDELINES FOR IMPROVING ENERGY EFFICIENCY
Dos Don’ts
P Undertake regular energy audits to identify energy saving potential P Do not be stagnant
P Sensitize plant personnel on the benefits of energy conservation P Do not always believe in what you hear
P Encourage people to provide ideas for energy savings and reward them P Do not look for only short-term benefits
P Promote group activities for information sharing at cluster level P Do not be afraid of adopting new technologies
P Search constantly for energy-efficient technological solutions P Do not always depend on in-house technical
P Avail external expertise to develop and undertake technological upgradation capacity
P Participate in workshops and training programs on energy efficiency P Do not think low-cost solutions are always
improvements economical
P Share success stories and discuss energy efficiency improvement strategies P Do not be apprehensive to approach banks for
with co-entrepreneurs loans to invest in energy-efficient technologies

ENERGY AUDIT wastage in major equipment/processes. In a preliminary energy audit study, one
basically relies on the data supplied by the unit or panel readings from meters installed
What is energy audit? in the industry.
Energy audit indicates the ways in which different forms of energy are being
used and quantify energy use according to discrete functions. Energy audit Detailed energy audit
does not provide the final answer to the problem. It identifies where the potential A detailed energy audit goes much beyond the quantitative estimates of cost
for improvement lies, and therefore, where energy management efforts must and savings. It is generally preceded by a plant visit, which is also called a
be directed. Energy audit is broadly classified as: preliminary energy audit and scoping study or preliminary energy audit, wherein the scope of the audit
detailed energy audit as explained below. assignment is discussed in detail with the plant personnel. The study involves
detailed mass and energy balance of major energy-consuming equipment. The
Preliminary energy audit system efficiencies are evaluated and measures are identified for improving the
In a preliminary energy audit, the entire audit exercise can be divided into three end-use energy efficiency. The study proposes specific projects/feasibility studies
steps. Step 1 identifies the quantity and cost of the various energy forms used for major retrofitting/replacement proposals, providing a cost-benefit analysis
in the plant. Step 2 identifies energy consumption at the department/process of the recommended measure. The duration of the audit is a function of the size
level. Step 3 relates energy input to production (output), thereby highlighting energy and complexity of the plant, the areas to be covered under the study, and so on.

INCENTIVE SCHEMES FOR USING RENEWABLE ENERGY

MNRE (Ministry of New and Renewable Energy) provides support for development metre of dish area for solar concentrating systems, and Rs 1750 per square metre
renewable energy projects. The schemes that are applicable for fruits and vegetable of collector area for FPC (flat plate collector)-based solar air heating systems/
processing industries are given below. dryers will be provided to commercial/industrial organizations.
1. Scheme for solar energy devices and systems
Under this scheme financial assistance is provided by MNRE for promotion of 4. Biogas plants
solar water heating systems, solar air heating systems, solar buildings, solar The ministry has started a scheme ‘Biogas based power generation program’. The
photovoltaic devices, and products such as street lights. There are different levels central financial assistance for such projects will be limited to a maximum of Rs
of incentives for the different devices. 30 000 to 40000 per kW depending upon capacity of the power generating projects
or 40% of the plant cost, whichever is lower, in the range of 3 kW to 250 kW.
2. Solar power projects
Support for maximum of 50-MW grid interactive solar power project (this includes 5. Small wind hybrid systems
both solar photovoltaic and solar thermal power projects) is given under the Small wind energy systems namely, water pumping windmills, aero-generators
scheme. MNRE provides generation based incentives through IREDA of a and wind–solar hybrid systems are useful for meeting water pumping and small
maximum of Rs. 12 per kWh to the eligible projects, which are commissioned by power requirements. The ministry provides financial assistance up to 50% of the
31 December, 2009, after taking in account the power purchase rate (per kWh) ex-works cost of water pumping windmills, (except for un-electrified inlands for
provided by the State Electricity Regulatory Commission or utility for that project. which up to 90% of the ex-works cost) and 50% to 75% of the cost of hybrid
3. Solar air heating systems and steam generators system.
for industrial applications Above details given are the brief of the various schemes of MNRE, for more detail
To promote solar air heating/steam generating systems, financial support in the please visit the MNRE website www.mnre.gov.in
form of 35% of the cost of system, subject to a maximum of Rs 3500 per square

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 Small Industries Development Bank of India
SIDBI was established on April 2, 1990 under an Act passed by Indian Parliament as the Principal Financial Institution for Financing, Promotion and Development
of industries in the small scale sector and to coordinate the functions of other institutions engaged in similar activities.

Mission
"To empower the Micro, Small and Medium Enterprises (MSME) sector with a view to contributing to the process of economic growth, employment generation and balanced
regional development."
SIDBI has been supporting the MSME sector with various innovative schemes and has brought special products for addressing the requirements in the
areas of cleaner production measures and also energy efficiency with the support of various multilateral agencies, brief details of which are as under :-

SIDBI - Japan Bank for International Cooperation (JBIC) partnership:-

SIDBI and JBIC have collaborated with an objective to promote energy saving projects in MSME sector by providing financial assistance through direct finance and
refinance through select PLIs/NBFCs thereby contributing to environmental improvement and economic development in the country. Assistance under the scheme
will be provided on softer terms to install equipments, changing the processes and directly associated activities with the installation as per the approved Equipment
/ Activity List. MSMEs may also avail the benefits of carbon credit due to reduced emission of CO2.

SIDBI - KfW partnership:-

A new scheme namely "SIDBI-KfW Scheme for Cleaner Production Measures for SSI/CETPs" was introduced in collaboration with KfW, Germany, in order to
encourage select industrial sectors in the MSME sector and Common Effluent Treatment Plants (CETPs) to adopt cleaner production measures, so as to reduce the
severe pollution loads, as well as to improve the profitability of the beneficiary units in the long run. Assistance is provided on softer terms for medium & long term
investments in integrated measures-machinery & equipment- to reduce the emission of hazardous substances.
Besides, SIDBI has been endeavouring to meet the diverse needs of the MSMEs through various tailor - made schemes.

Direct finance schemes of SIDBI

P Term Loan Assistance – For setting up of new projects & for technology upgradation, diversification, expansion etc. of existing MSMEs, for Service sector
entities & infrastructure development & upgradation.
P Various other schemes e.g. working capital, Inland Letter of Credit, Guarantee Scheme , Equity Support, Vendor Development Scheme & bill discounting facility
etc.

SIDBI has country-wide network of 74 branches to service the MSME sector efficiently:-

Agartala Baroda Ganktok Jamshedpur New Delhi Shillong

Agra Bhopal Gurgaon Jodhpur Noida Surat
Ahmedabad Bhubaneswar Guwahati Kanpur Okhla Thane
Aizawl Chandigarh Hosur Kochi Panaji Tirupur
Aligarh Chennai Hubli Kolhapur Patna Trichy
Alwar Chinchwad Hyderabad Kolkata Peenya Vapi
Ambattur Coimbatore Imphal Kozhikode Puducherry Varanasi
Andheri Dehradun Indore Kundli Pune Vijaywada
Aurangabad Dhanbad Itanagar Lucknow Raipur Visakhapatnam
Baddi Dimapur Jaipur Ludhiana Rajkot
Balanagar Erode Jalandhar Mumbai Ranchi
Bandra-Kurla Complex Faridabad Jammu Nagpur Rourkela
Bangalore Gandhidam Jamnagar Nashik Rudrapur

For further details please contact nearest SIDBI branch

Toll free number: 1800226753
Website: www.smefdp.net, www.sidbi.in
SIDBI has also setup following Associate Organisations to cater to specific needs of MSME sector:-
SIDBI Venture Capital Credit Guarantee Fund Trust SME Rating Agency India SME Technology
Ltd. (SVCL) For Small Industries (CGTSI) Of India Ltd. (SMERA) Services Ltd. (ISTSL)
Website:- www.sidbiventure.co.in Website:- www.cgtsi.org.in Website:- www.smera.in Website:- www.techsmall.com

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