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CHAPTER 5
ANALYSIS OF ENERGY CONSUMPTION AND ENVIRONMENTAL IMPACT
5.1 INTRODUCTION
The obstacles in improving environmental performance of the MSME sector are mainly
the lack of knowledge and information concerning environmental issues. MSMEs have a
perception that they have little or no impact on the environment due to their smaller scale
of operation. Any pro-environmental attempt by these organizations are hindered due to
lack of; financial support, expertise, and technology, etc. In such situations CP seems to
be suitable approach to contain the environmental damage occurring due to activities of
MSMEs. CP aims at reducing the negative environmental impacts in the production
process by advocating the efficient use of resources, thus helping industries to perform
economically better apart fi-om improving their environmental performance. Agro-based
industries are resource intensive industries in which the energy requirement, among
others, constitutes the major portion of input resources. The prime environmental impact
is associated with air pollution due to energy consumption. In the previous chapter,
production processes followed in the considered three agro-based industry clusters were
presented. It was understood that energy requirement in these sectors consists three types
of energy forms viz., electrical, labour and thermal energy. Study of energy consumption
pattern and associated environmental impacts facilitate finding disparities existing among
the enterprises within the cluster. Subsequently, estimation of energy conservation
potential and also associated reduction in environmental degradation can be estimated.
5.2 ENERGY AND ENVIRONMENT IN MSMEs - A CAPSULE OF
LITERATURE
It is widely recognized fact that MSMEs play a significant role in the economic
development of a nation. However, they also exert considerable pressure on the
environment, if not at the individual level but collectively at the cluster level. Many
researchers have demonstrated that this problem can be dealt with approaches that are
specifically relevant to the concerned region and the industry. But, the common goal is to
first understand the situation and then device methods to reduce the resource
consumption.
55
Johannes (2004) observes the core of CP implementation lies in identifying the flows of
mass and energy in a company for evaluating the efficiency of the use of materials, water
and energy. MSMEs have potential to create jobs and because they can be dynamic
vehicles for irmovation, must be given easy access to available advanced energy systems.
In this context, Scarpellini and Romeo (1999) opined that renewable energies represent
the most adequate resoiirce to MSMEs assuring continuity in energy supply without
dependence on fluctuating energy market. According to Viswanathan and Kumar (1999)
one of the issues associated with CP implementation is to significantly reduce GHG
emission and increase energy usage efficiencies. Ramachandra (1998) studied the rural
energy utilisation in Kamataka and found that energy is a vital input to rural industries
including agro-processing industries. It was suggested in the study that decentralised way
of meeting the energy requirements of industries would be the most appropriate way of
handling the energy situation in a region.
Study of energy consumption pattern and their associated environmental burden are
cornerstones for effective implementation of CP. Many studies have been conducted in
the agro-based food industries. Kaiman and Boie (2002) studied the implications of
energy management in German bakeries. They found that it was possible to reduce energy
consumption by about 6.5% of the then prevailing energy consumption level. They also
estimated Specific Energy Consumption (SEC) of 1.37 kWh per kg of processed flour
(4.93 MJ/kg). Bamgboye and Jekayinfa (2006a) have carried out energy consumption
pattern in palm kernel oil processing. They considered thermal, electrical and manual
energy consumption and brought out the total energy consumed for the operation. Further,
the energy use of different operations in the production was also estimated. Jekayinfa and
Bamgboye (2006b) also estimated the energy consumption in cashew processing in
Nigeria and estimated that the total energy intensity in the cashew nut mills varied fi-om
0.21 to 1.161 MJ/kg. Different studies on energy requirement for rice processing revealed
that there was no agreement on the energy requirement. This is attributable to the fact that
there is considerable variation amongst different mills in terms of paddy quality, type of
milling, and parboiling methods adopted. In a study EC - Asean Cogeneration program
(1998) in Thailand, white rice-mill processing required 30 kWh/ton (108 MJ/ton), while
parboiled rice milling required up to about 60 kWh/ton (216 MJ/ton). The other study
conducted by Kapur et al. (1999) in India, reported parboiling as the most energy
56
intensive process consuming about 241 to 425 MJ/tonne of paddy and milling required
79.2 to 164 MJ/tonne of paddy.
Atul et al. (2011) undertook a study on sources of environmental pollution from cashew
processing. According to the study, even though the pollutant emission from single unit
is low, collective emissions load of all the units in the cluster causes considerable
environmental degradation. The cashew nut processing by cooking i.e., steam roasting
process is relatively less pollution intensive. It is a better alternative process for roasting
and hence may be adopted to reduce the environmental impact. Natarajan, et al. (1998)
considered rice husk generated as a by-product during rice milling process and used
this as a renewable energy source in the production process. It was found that the husk
was less polluting due to its low sulphur and heavy metal content. Mamasaray et al.
(1999) concluded that converting rice husks into heat, steam, gas or liquid fuel would
benefit countries that have limited or no conventional energy resources. Promoting the
use of rice husk by the energy sector would curb local environmental problems, such as
rice husk dumping, open burning and can mitigate Green House Gas (GHG) emissions.
In this literature backdrop it is very clear that the energy use analysis followed by
environmental impact assessment not only helps in creating a sound case for
implementation of CP, but also assists in improving the economic performance of
MSMEs.
5.3 ENERGY CONSUMPTION PATTERN IN AGRO-BASED INDUSTRIES
Energy consumption pattern of the three agro-based industry clusters selected in this study
are presented in the following sections. In this energy analysis, thermal, electrical and
manual energies are considered. A researcher administered structured questionnaire was
used in all the clusters to fetch the details of the type of energy carrier, and quantum of
energy used. Using the primary data collected from the MSME units in each of the three
clusters, SEC, and total energy used are determined and projection of energy requirement
for the whole cluster was made.
5,3.1 Bakery Cluster (Shimoga)
In bakeries the thermal energy is mainly required for baking operation. Thermal energy in
the cluster was used to be obtained conventionally by burning the wood. However, with
the development of electrical ovens, bakeries shifted to use electricity for thermal energy.
57
Later with the availability of Liquefied Petroleum Gas (LPG), LPG ovens were also used
which is considered to be one of the clean fuel available for this sector. Owing to cost
aspects, bakery operators once again started shifting from LPG fired ovens to diesel fired
ovens. At present diesel cost is considered as the lowest with 3-4 years of pay back period
for installing new diesel ovens. Apart from thermal energy, bakeries require electrical
energy as well to operate various bakery equipments and for front-shop operation. Manual
energy is the other energy source considered in the CP assessment of this industry. Bakery
cluster when compared to other agro-based industrial clusters in this study, does not use
any sort of biomass these days.
Table 5.1 provides 'energy consumption pattern' in bakeries based on the sampled units in
the cluster. The number of bakeries in the cluster is not exactly known as there are no
authentic data available. In consultation with the bakery operators, it was approximated at
around 175 units processing about 4500 tons of flour annually out of which about 1000
ton of flour is processed in the 40 sampled units. A total energy of 6.93 TJ in the sampled
units and 30.08 TJ in the entire cluster are consumed annually.
Table 5,1: Average Annual Energy Requirement in Bakeries
Type of Energy Fossil Fuel
Electricity
Manual
Total
Total Annual Energy 5.25
1.55
0.134
6.93
Projected Annual 22.78
6.70
0.60
30.08
% Share of 75.7
22.3
2.0 100
Fossil Fuel • Electricity IVIanual
2%
Figure 5.1: Energy Consumption Pattern in Bakery Industry
58
5.3.2 Cashew Processing Cluster (Dakshina Kannada and Udupi)
Cashew processing requires energy in different forms. This industry is labour intensive
and requires skilled labourers for shelling and peeling. Women workers are best suited for
these operations. Other processes like raw nut drying, grading and packing may employ
male workers. Apart from the labour energy, it essentially requires thermal energy for
roasting and drying processes. Thermal energy is derived mainly from the cashew cake
which is a by-product of this industry. Fire-wood is also used as thermal energy source in
those locations where it is available easily. In few instances, electrical energy is also used
for drying purposes. However, electrical energy is mainly required to operate shelling
machines, peeling machines, and packing machines. Fossil fuel (petrol/diesel) is
occasionally used during power failures to operate machines/generate power.
Table 5.2: Average Annual Energy Requirement for Cashew Processing
Type of energy carrier
Biomass
Electricity
Fossil Fuel
Manual
Total
Total Annual Energy Used in
Sampled MSMEs TJ
100.19
9.53
13.17
40.26
163.15
Projected Annual Energy Required the Cluster TJ
341.34
32.50
44.8
137.15
555.79
• Biomass • Electricity
8% J
6%
^ M
% share of total energy
61.41
5.84
8.06
24.60
100
Fossil Fuel « Manual
• 1 ^ ^ ^ ^ ^
Figure 5.2: Energy Consumption Pattern in Cashew Processing Industry
Total number of cashew processing units in the cluster is about 160, which processes 1.5
Million tons of raw cashew nuts annually out of which 44,000 tons of cashew is estimated
to be processed annually in the 40 sampled units. Total annual consumption of energy is
59
162.9 TJ in the sampled units and it amounts to 555.6 TJ in the cluster. Table 5.2 provides
the estimation of average annual consumption of energy in surveyed units and its
projection to the entire cluster.
Thermal energy constitutes about 61.4% and labour energy accounts for 24.6% in the
total energy consumed. The labour energy and electricity have a share of 5.84% and
8.06% as shown in figure 5.2. The average annual energy use per enterprise in the cashew
cluster is 4.00 TJ and the SEC is 3.73 MJ per Kg of raw cashew nut processed.
5.3.3 Rice MiU Cluster (Gangavati)
Rice processing is highly energy intensive requiring thermal and electrical energy for its
processing. In the present research work only par boiled rice processing is considered
because it is having high pollution intensity. Par boiling is an optional processing that
requires steam and hot water derived from burning rice husk generated from rice milling
process. After parboiling, the paddy is milled in a series of machinery which operate using
electrical energy. To obtain high quality cleaned rice, milling in modem rice mills are
done with latest machineries which are energy intensive thus increasing the energy
demand of rice-mills.
Table 5.3: Average Annual Energy Requirement for Rice Mills
Type of energy carrier
Biomass Electricity Fossil Fuel
Manual
Total
Total Annual Energy Used in
Sampled MSMEs TJ
1024.93 104.70
13.99 0.83
1144.45
Projected Annual Energy Required the
Cluster TJ
3711.50 361.51 48.31 2.88
4124.22
% share of total energy
89.5 % 9.14% 1.22%
0.072 %
100 %
In the present work total 40 units were sampled randomly out of 145 processing units in
the MSME cluster under study. The total annual quantity of paddy processed in the
cluster was about 11 Million tons out of which 3.2 Million tons was estimated to be
processed annually in the sampled units. A total of 1144.45 TJ of energy in the sampled
units and 4124.22 TJ in the cluster are consumed annually. Table 5.3 provides the
estimation of average annual consumption of energy in the sampled units and its
projection to the entire cluster.
60
Thermal energy requirement is predominent in rice milling constituting almost 90% of the
total energy. Requirement of electrical energy to operate machines is about 9%, with
fossil fuel accoumting for about 1.25%. The remaining feeble share goes to manual
energy as shown in figure 5.3. The average annual energy required per enterprise in this
cluster is estimated at 25.5 TJ while the SEC is around 3.75 MJ per kg of paddy processed
in this industry.
• Biomass " Electricity
1%
^ 9%
Fossil Fuel
0%
Manual
.^-2980
Figure 5.3: Energy Consumption Pattern in Rice-Milling Industry
5.4 ENVIRONMENTAL IMPACT OF AGRO-BASED INDUSTRIAL CLUSTERS
The measurement of environmental implications provides an insight that allows
organisations to focus on achieving the most meaningful reductions. In agro-based
industries consumption of energy, water and generation of waste is the source for
environmental pollution. Water is being used in the agro-based industries for different
purposes. In bakeries, it is used as an ingredient and also for cleaning purposes. In the
cashew processing industries it is used for steam generation and for cleaning purposes.
The rice mills use water for steam generation and for soaking purpose in parboiled rice
processing. The quantity of water required in bakeries and cashew processing may be
controlled by adopting conservation measures and are not of much concern from an
environmental perspective. Rice mills use huge amount of water to process paddy without
the use of chemicals. It contains organic matter which when discharged repeatedly in huge
quantities may cause stagnation and putrefies causing pollution.
Kuvempu University Library Jnana Satiyadri, Shankaraghatta
61
Other soiirce of pollution is through generation of solid wastes. In bakeries, the solid
waste generated is from spill overs and leftovers. In cashew processing and rice mill
industries, the solid wastes are cashew nut shell and rice husk respectively along with the
ash generated from burning bio-mass. Cashew nut shell and rice husk have now found
altemative uses. Considering the above facts and localized nature of pollution, the
pollution caused by water use and solid wastes generated are not serious and hence not
included for a detailed study in the present research work. The major environmental
impact in agro-based industries is the air pollution caused due to energy consumption in
different forms. Thus estimation of air pollution, which not only has the local effect but
can have the global impact as well, is carried out in a greater detail in this research work.
5.4.1 Emission Estimation Procedure
Air pollution due to energy use is expressed in terms of generation of Green House Gases
(GHGs) and other pollutants. For stationery combustion, they include Carbon Dioxide
(CO2), and five major non-COa GHGs: Methane (CH4), Nifrous Oxide (N2O), Carbon
Monoxide (CO), and Nitrogen Oxides (NOx), and Non-Methane Volatile Organic
Compounds (NMVOC). The ftiels also contain sulphur and emit Sulphur Dioxide (S02),
which is not a GHG. In this study major GHGs are considered and their emissions due to
fiiel combustion are estimated using Intergovernmental Panel on Climate Change (IPCC)
guidelines. Estimation of CO2 emission is relatively simple and more accurate due to the
fact that factors used are the ftinction of ftiel properties.
The emission of each GHG from stationery sources are calculated by adopting the
procedure outlined in IPCC (2006) Guidelines for National Greenhouse Gas Inventories.
The procedure involves determining the fuel consumption in mass units first and
converting it into energy content of the fuel to be expressed in Tera Joules. Next, the
energy consumption thus calculated is multiplied with the default emission factor for each
GHG of the fuel to get the emission quantity. Basically, carbon emissions are classified
into Direct and Indirect emissions. The Greenhouse Gas Protocol (GHG Protocol) defines;
• Scope 1: Direct GHG emissions
Direct GHG emissions are emissions from sources that are owned or controlled by the
reporting entity. For example, emissions from combustion in owned or controlled boilers,
fumaces, vehicles, etc.
62
• Scope 2: Indirect GHG emissions
These are emissions that are a consequence of the activities of the reporting entity, but
occur at sources owned or controlled by another entity, i.e. emissions due to purchased
electricity, heat or steam.
• Scope 3: Other indirect emissions
Other activities are included here such as the extraction and production of purchased
materials and fuels, transport related activities in vehicles that are not owned or controlled
by the reporting entity, electricity-related activities like transmission and distribution
losses not covered in Scope 2, outsourced activities, waste disposal, etc.
Table 5.4 provides the emission factors used in the estimation of GHGs in the three
MSME clusters for various energy carriers. Since emission factor for rice husk and
cashew cake are not directly available in the IPCC guidelines, a common emission factor
given for the biomass is used.
SI. No.
1
2
3
4
5
Table 5.4: Emission Factors (Source: IPCC, 2006)
Name of the
Pollutant CO2
CH4
N2O
CO
NOx
Emission Factor for Diesel
Kgsof C02/tonne
3171.48
0.128
0.025
0.65
8.67
Emission Factor for LPG
KgsofCOi/ Tonne 3098.72
0.046
0.0046
0.26
6.93
Emission Factor for Biomass
1890
0.441
0.0588
75.60
1.89
Emission Factor for
Wood 1646.4
0.441
0.0588
29.40
1.470
5.4.2 Environmental Impact assessment in the Sampled Clusters
This section provides the air pollution caused by the selected agro-based MSME clusters
due to energy consumption. Various GHGs are estimated in all the three clusters and it is
based on the computation of average GHGs emitted from the sampled units in the
respective clusters and its annual projection for the entire cluster. The emission intensities
are specified for one ton of raw material processed. Table 5.5 illustrate the GHG
emissions calculations for bakery cluster. Pollution intensity caused by this sector is
63
highest when compared to other two sectors due to its dependence on fossil fuel;
conversely the total pollution caused by the cluster is lowest owing to annual processing
quantity.
Table 5.5: GHG Emissions - Bakery Cluster
Scope 1 Emissions due to fuel consumption
Emissions in kg per ton of wheat flour processed CO2 380.6
CH4 1
Scope 2 CO2 emissions due to purchased electricity is 354.6 kg/ton of wheat flour processed Projected Annual GHG Emission of the Cluster in tons of GHG
2153.24
D.OlO N2O
0.00173 CO
0.053 NOx 0.938
Global Warming Potential (GWP) rScoDe 1 & 2)
735.94 kg C02eq.
0.058 0.010 0.312 5.36
Cashew processing is relatively less polluting among the considered clusters. In table 5.6
air emissions calculations for the cashew processing cluster. This cluster depends on the
biomass as energy source for its thermal energy requirement.
Table 5.6: GHG Emissions - Cashew Processing Cluster
Scope 1 Emissions due to fuel consumption
Emissions in kg per ton of raw cashew nut processed CO2
249.68 CH4
0.0554
Scope 2 CO2 emissions due to purchased electricity is 57.23 kg/ton of raw cashew nut processed Projected Annual GHG Emission of the Cluster in tons of GHG
37452
Glol
8.31
N2O 0.00746
CO 8.269
NOx 0.282
>al Warming Potential (GWP) (ScoDe 1 & 2)
310.37 kg CO2 eq.
1.12 1240.35 42.3
Table 5.7: GHG Emissions
Scope 1 Emissions due to fuel consumption
- Rice MiU Cluster
Emissions in kg per ton of paddy processed CO2 221.5
CH4 0.110
Scope 2 CO2 emissions due to purchased electricity is 87.10 kg/ton of paddy processed Projected Annual GHG Emission of the Cluster in tons of GHG
243650
N2O 0.0147
CO 3.51
Global Warming Potentia (Scope 1 & 2)
315.46 kg of C02eq
121 16.17 3861
NOx 0.578
(GWP)
635.8
64
As rice mill cluster also depends on biomass energy, the air pollution intensity for rice
mill cluster is similar to cashew processing cluster. Owing to huge quantity of paddy
processed in this cluster, annual GHG emission of the cluster is highest as illustrated in
table 5.7.
5.5 SUMMARY
The study of quantity of energy consumed and energy consumption pattern revealed that
the thermal energy is predominant in the agro-based industries. Further, a wide variation
in the energy consumption is observed amongst the MSME units in a product cluster as
observed in Figure 5.4.
• SEC • Coefficient of Variation
Bakery Rice Mill Cashew
Figure 5.4: Variation in SEC amongst the Three Product Clusters.
This could be attributed to difference amongst units in a cluster in terms of lack of
knowledge, expertise, and financial ability to adopt effective energy management
techniques. Another reason might be that they operate on short term profit goal, and do
not give attention to conserve energy which may yield results on long term basis.
The results of the study reveal that there is wide disparity in energy consumption amongst
the three MSME clusters. The environmental pollution associated with energy
consumption is also estimated in terms of GWP (Global Warming Potential) using IPCC
guidelines. The difference in SEC values is understandable because the products are
different despite they come under agro-based food industry classification. The production
processes are quite different and so also is the energy requirement thus resulting in
65
different SEC values for each of the clusters. Further, different operating conditions
prevailing in the three geographical locations, the attitude of entrepreneurs and labourers,
quality of energy carriers used, technological aspects, etc., have also contributed to this
variation.
Looking at Table 5.8, it may be observed that SEC values and emissions of cashew
processing and rice mills are comparable as biomass constitutes major energy source.
Bakery cluster deviates fi-om other two and proves to be highest energy consumer and also
has high GWP per unit of raw material processed.
Table 5.8: Estimated SEC and GWP in the Three Agro-Based Industries
Agro-Based Cluster
Bakery
Cashew Processing
Rice Mills
Energy Carrier
Fossil Fuel Electricity
Manual Biomass
Electricity Fossil Fuel
Manual Biomass
Electricity Fossil Fuel
Manual
Specific Energy Consumption
MJ/kg 5.110 1.450 0.140 2.280 0.230 0.310 0.910 3.375 0.328 0.044 0.003
SEC of the Product MJ/kg
6.7
3.73
3.75
GWP gms of
CO2 eq. /kg
735.94
310.37
315.46
With the understanding of the energy consumption pattern, energy efficiency (SEC) and
its variation amongst the three product clusters, the next chapter looks at the assessment of
CP in the three MSME clusters.
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