Scale-up of Deployment of Anaerobic Digester

8/15/2019 Scale-up of Deployment of Anaerobic Digester

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Scale-up of Deployment of Anaerobic Digester Technology at Public

and Commercial Institutions: Challenges and Opportunities in India

F I NAL PROJECT REPORT

Submi tted By

Nikita Elizabeth Joseph

In partial fulfillment of the requirement for the

Degree of M aster of A rts in

Sustainable Development Practice

May 2015


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DECLARATION

This is to certify that the work that forms the basis of this project “ Scale-up ofdeployment of anaerobic digester technology at public and commercial

institutions: Challenges and Opportunities in India” is an original work carried out

by me and has not been submitted anywhere else for the award of any degree. I

certify that all sources of information and data are fully acknowledged in the project

report.

……………………….. ……………………….......

Nikita Elizabeth Joseph Place and Date


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CERTIFICATE

This is to certify that Ms Nikita Joseph has carried out her major project in partial

fulfillment of the requirement for the degree of Master of Arts in Sustainable

Development Practice on the topic “ Scale-up of deployment of anaerobic digestertechnology at public and commercial institutions: Challenges and Opportunities in

India “during January 2015 to May 2015. The project was carried out at the office of

Green Brick Eco Solutions Pvt Ltd. The report embodies the original work of the

candidate to the best of our knowledge.

May 29th 2015

………………………………. …………………………………...

External Supervisor Internal Supervisor

Sandeep Garg Martand Shardul Founder, Green Brick Eco Solutions Pvt Ltd Research Associate, TERI

……………………………………….. Dr Shaleen Singhal

Head of the Department

Department of Policy Studies

TERI University

New Delhi


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Table of ContentsLIST OF ABBREVIATIONS AND SYMBOLS ......................................................... 7

LIST OF FIGURES ...................................................................................................... 9

LIST OF TABLES ....................................................................................................... 9

CHAPTER 1 ............................................................................................................... 11Introduction ............................................................................................................. 11

Background and Rationale of the project ............................................................... 14

Limitations of the study .......................................................................................... 16

CHAPTER 2 ............................................................................................................... 17

Statement of the problem ........................................................................................ 17

Methodology ........................................................................................................... 17

CHAPTER 3 ............................................................................................................... 18

Anaerobic Digestion Technology ........................................................................... 18

Biochemical Process ........................................................................................... 18

Feedstock ............................................................................................................. 20

Biogas utilization .................................................................................................... 20

Storage ................................................................................................................ 20

Bottling ................................................................................................................ 21

Distribution ......................................................................................................... 21

Utilization ............................................................................................................ 21Biogas as an energy source ..................................................................................... 22

Benefits of Anaerobic Digestion ............................................................................. 24

Limitations of AD ................................................................................................... 26

AD technology around the world ............................................................................ 28

CHAPTER 4 ............................................................................................................... 33

Status of AD technology in India ........................................................................... 33

Implementation strategies for biomethanation in India .......................................... 35 Accelerated Programme on Energy Recovery from Urban Wastes .................... 36

Financial assistance ............................................................................................ 37

Policy making and planning ................................................................................... 39

Electricity act ...................................................................................................... 39

The Municipal Solid Wastes (Management and Handling) Rules, 2000 ............ 39


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TERI The Energy and Resources Institute

TPD Tonnes Per Day

TPY Tonnes Per Year

UK United Kingdom

UN United NationsUNDP United Nations Development Programme


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LIST OF FIGURES

Figure 1: Functional interdependencies at development phase of TIS ....................... 56

LIST OF TABLES

Table 1: Stages in Anaerobic digestion process ......................................................... 19

Table 2: Composition and energy value of biogas (Khoiyangbam et al, 2011). ........ 22

Table 3:Equivalency of biogas to other fuels (Khoiyangbam et al, 2011). ................ 23

Table 4: Cost comparison to other sources of power (Ravindranath and Balachandra,

2009) ........................................................................................................................... 24

Table 5: Cost comparison to kerosene stove (Ravindranath and Balachandra, 2009)

.................................................................................................................................... 24

Table 6: Installed capacity of waste to energy and biogas based power systems ...... 34

Table 7: Statewide Installed capacity of power from waste to energy ....................... 34

Table 8: Financial Assistance for grid power generation from biogas ....................... 37

Table 9: Financial Assistance for energy recovery from urban wastes ...................... 38

Table 10: Financial Assistance for Biogas Fertilizer Plants (BGFP) for Generation,

Purification/Enrichment, Bottling and Piped Distribution of Biogas ......................... 38Table 11: Population growth and impact on overall waste generation ...................... 41

Table 12: The potential of energy generation from MSW ......................................... 41

Table 13: Gas Production and quality ........................................................................ 44

Table 14: Costs of plant operation .............................................................................. 45

Table 15: Development phases of a TIS system ........................................................ 50

Table 16: Interviewee Sample .................................................................................... 51


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ABSTRACT

Renewable Energy technologies have been identified as an important means of

meeting energy demands in times of depleting fossil fuel reserves and environmental problems caused by use of conventional energy sources. Among others, biogas

energy from Anaerobic Digestion or biomethanation of organic waste generated in

urban areas is a promising technology that has great potential of serving as a clean

energy source and as a decentralized waste management solution. Urban entities

that generate significant quantities of organic waste such as large kitchens, housing

societies, public and private office complexes and other institutions, market areas etc

are ideal candidates for AD systems through set up of medium and large scale

anaerobic digesters.

In this paper, an attempt has been made to analyze biogas as a source of energy: its

potential applications, case studies of existing projects, its advantages and

drawbacks. The status of biomethanation technology for organic wastes in India, its

scope and drivers for expansion have been explored. The existing regulatory

framework and policy support and incentives offered by the government have also

been reviewed. There are many bottlenecks in the way of their ample diffusion of new

and emerging technologies such as AD. Besides understanding these barriers, this

study has adopted a framework for analyzing the hindrances to expansion in

deployment of this technology, namely the Technology Innovations Systems (TIS)

framework. This is carried out by conducting interviews with a sample of key

informants who are experts in the field and based on the analysis of its outcomes,

several policy recommendations have been drawn for bettering the prospects of scale

up of this technology.

KEYWORDS: Anaerobic Digestion, Anaerobic Digesters, Biomethanation, MSW,

Organic waste


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CHAPTER 1

Introduction

India, with its population of over 1.2 billion is growing annually at the rate of

1.2%.Among other issues; energy insecurity is one issue that needs to be addressed

as India will face increasing energy shortages due to depleting fossil fuel reserves

and lack of affordable energy sources.

Globally, India is the fourth largest consumer of energy, preceded only by countries

such as United States, China and Russia. Rapid population growth and economic

development in the past decade have meant an inevitable increase in energy demand

and consumption, which is only likely to grow further . It is projected to reach 1,464

Mtoe in 2035, increasing by a CAGR of 3.1% from 2009 to 2035, which is more

than double the world’s energy demand at a CAGR of 1.3% for the same period

(IEA 2012). This demand growth would come from all sectors such as industry,

transport, construction and agriculture and is expected to be met largely by coal and

other hydrocarbons.

An excessive reliance on such non renewable energy sources come with its inherent

risks such as their depletion, import dependence and climatic changes due to carbon

emissions. An approximate energy deficit of 11,436 MW which is equivalent to

12.6% of peak demand in 2006 is being experienced as energy demand from various

sectors is increasing substantially (Rao et al 2010).This energy generation gap can be

met from RETs .The need for affordable, clean and renewable energy to enhance

sustainable development has been reiterated recently by the world energy counciland the UN commission on sustainable development.

Renewable energy, excluding large hydro projects already account for 9% of the

total installed energy capacity, equivalent to 12,610MWof energy while along with

large hydro, the capacity is more than 34%, i.e., 48,643 MW. The country has an


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estimated renewable energy potential of around 85,000MW from commercially

exploitable sources, i.e. wind, 45,000 MW; small hydro, 15,000MW and biomass/bio

energy, 25,000 MW (Kumar et al 2010)

Among all the renewable sources of energy, bio energy does not figure in most

energy analyses as it is regarded chiefly as “non -commercial” energy (TERI). Butyet, biomass reportedly satisfies around 90 and 40% of rural and urban household’s

energy needs. It has been traditional fuel source for direct combustion but this

process produces pollutants such as dust, nitrogen and sulphur oxides.

Biomass usage as a source of energy is of interest because it is renewable,

sustainable and a relatively environment friendly source of energy. Basically, energy

is obtained from biomass by capturing of the solar energy and carbon from the

ambient CO2 in growing biomass, which is then converted to bio energy or is used

directly as a source of heat and power. Biomass energy generation is regarded as one

of the most cost effective as compared to other sources such as wind, hydro and solar

energy as it involves the least per unit production cost and capital investment.(Rao et

al)

The bio energy potential from MSW, crop residue and agricultural waste, wastewater

sludge, animal manure, industrial waste which includes distilleries, dairy plants, pulpand paper, poultry, slaughter houses, sugar industries is estimated to be around

40,734 Mm3/year (Rao et al, 2010). Biomass can be converted into a variety of

energy forms such as heat, steam, electricity, hydrogen, methane, ethanol and

methanol. The efficiency rate of the various options differs in terms of energy net

yield, water pollution, conversion efficiency; capital investment.

Among the different biomass to energy conversion techniques, anaerobic digestion(AD) of municipal organic waste is an increasingly popular method for treatment of

municipal organic waste to produce biogas for energy needs.Anaerobic biogas

digestersare airtight reactorsin which organic wasteis decomposed and transformed

into biogas. The remaining sludgecontains many nutrients and can be used in

agriculture. It is also regarded as a sustainable solution for treating municipal solid

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waste especially in developing nations where management of urban waste is a huge

problem.

The organic/food component of MSW is normally dumped along with all other kinds

of waste into landfills. This disposal method involves various drawbacks such asmethane emission into the atmosphere, land scarcity for landfill sites in urban areas,

high costs of waste transportation and burial and groundwater contamination.

The biogas produced from the AD process is considered as a renewable energy

source because under controlled conditions the biogas produced (consisting mainly

of methane and carbon dioxide) can be used for energy production, contributing to

replace fossil fuels. It can be burnt directly to produce heat for heating and other

purposes.

The gas can also be used in CHP plants where heat can be supplied to public

buildings, horticultural glasshouses, and small-scale industry.

Another increasingly popular method is to upgrade biogas to produce pure methane

that can be injected into gas grids for low-pressure provision of gas supply to the

community or can be used as a vehicle fuel. Although this is undertaken at a large

scale level, if this can be extended to the community or small scale enterprise level itwould greatly enhance its renewable energy potential.

Biomass is gradually being considered as a competitive energy resource in policy

circles as well. Market based incentives like tax benefits and institutional support

like capacity building has encouraged development of newer technologies such

large-scale adoption of gasification and combustion technologies for electricity

generation using a variety of biomass. The bio energy sector in India is currently primarily driven by Government of India’s initiatives. Key governm ent ministries

such as the MNRE and the MoEF have had a significant role in promoting bio

energy.


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Anaerobic digestion has the potential to deliver uses in so many different ways and

its application at a community and private enterprise level is still an area to be

explored, hence this paper will attempt to gauge its potential as a renewable energy

technology among commercial and institutional entities in urban areas of India.

Since large private and public commercial institutions in the country are sources oflarge amounts of organic waste they are the most suited for adoption of AD

technology.

Background and Rationale of the project

Compared to most renewable energy technologies, biogas energy has higher climate

change mitigation potential as its generation from organic wastes replaces methanethat would otherwise be dissipated from them into the atmosphere. Yet, biogas is

also a renewable energy source that has high untapped potential, especially in a

country like India and this is not addressed by current climate change policy.

(Schmidt and Dabur , 2012)

India’s national program on household biogas plants has been in inception since

1982 and since then four million family size biogas digesters have been installed.

(Tripathi, 2010). However, the potential other uses of biogas through the use of

large-size plants (>100 m3 digester size) is something that has India has been late in

exploring. Family size biogas plants allow for its use only as a fuel source for

heating or cooking at the household level whereas medium and large size plants (100

m3 capacity) can be a potential replacement for natural gas applications by using it in

gas engines for electricity generation and also as a vehicle fuel. Although the

government had undertaken several WTE projects, it has met with limited success or

near failure. This is in contrast to several other countries such especially of Europethat have met with high success in diffusion of large scale biogas energy projects.

(Poeschl et al, 2010).

Renewable energy from biomass is one of the most efficient and effective options

among the various other alternative sources of energy currently available as it


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requires less capital investment and involves less per unit production costs as

compared to other sources such as solar, wind and hydro power. (Rao et al, 2010)

Yvonne Vogeli, Chris Zurbrugg (2008) state that AD of organic solid waste is a

promising technology in developing countries with tropical climate and that biogas plants in urban areas have a great potential. Nguyen et al (2014) studied how

Anaerobic digestion (AD) was introduced in Vietnam at a small scale and termed it a

promising method to treat MSW in cities by analyzing the energy potential of food

waste from urban areas

Zurbrugg (2008) conducted an evaluation study of various biogas plants operating in

market areas of South India to unveil the potential and challenges of dissemination of

this potential energy source and treatment option for organic fraction of MSW. Heeb

(2009) emphasized on the importance of providing dependable data on the real scale

application of this technology in terms of technical, economic and operational

feasibility.

Mueller (2007) points to how information on the status quo of low tech anaerobic

digesters is lacking due to the fact that biomethantion of organic solid waste is an

issue that has come up only in the recent past. Gebreegziabher et al (2014) havestudied the potential applications of biogas plants among the urban populations of

South Africa and have identified critical conditions for its success. Pfeiffer and

Mulder (2013) have analyzed the factors that accelerate the diffusion of NHRE

technologies and found incentivizing economic and regulatory instruments, a

favorable policy environment are contributing factors to this.

The large scale adoption and diffusion of RETs are hindered by several barriers thatneed to be overcome. In order to analyze these, several frameworks have been

devised and one of these is the ‘ Technological Innovation Systems’ (TIS) framework

by Hekkert et al, that extends insights into how their diffusion can be augmented via

policy measures. Using this framework, I propose to conduct a study on the barriers

to expansion of biogas energy, specifically in relation to the application of


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biomethanation technology through deployment of anaerobic digesters in the urban

institutions such as housing societies, large kitchens, hotels, hostels, office

complexes and market areas. Through this I intend to determine the prospects and

challenges of deploying medium and large scale anaerobic digesters and scope for its

expansion.

Limitations of the study

Deployment of anaerobic digesters in urban areas for treatment of organic waste and

as a viable energy source is a very new concept and that is still picking up and

awareness levels regarding this are low. Government records for the total installedcapacity of energy through biomethanation, both grid and off-grid is also very

limited.


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CHAPTER 2

Statement of the problem

The study deals with scope and challenges of deployment of anaerobic digesters inurban areas. The specific sub objectives are:

Examine the policy environment for promotion of biogas energy in India. Identify barriers to adoption of medium and large scale anaerobic digesters in

urban areas. To suggest strategies for overcoming the identified barriers.

Methodology

Literature survey on major anaerobic digestion technologies in India andtheir successes and failures.

Peruse policy documents on government incentives and schemes for bio

energy- specifically in the context of biomethanation for organic wastes in

urban areas. Sector Reports and research papers on biomethanation, its applicability and

case studies of biomethanation projects set up in India and abroad. In-depth interviews with pre identified stakeholders that are responsible for

spread of the technology, i.e. Entrepreneurs, Government officials, Technical

experts, Industry Associations, and Potential Investors. Hence at the end of

the interview process, the most significant barriers; to the scale up of this

technology will be arrived at.


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CHAPTER 3

Anaerobic Digestion Technology

Bi ochemical Pr ocess

A biogas plant is a set-up device that converts fermentable organic matter into a

combustible gas and matured organic manure. It works on the process of anaerobic

decomposition/digestion whereby in the absence of air, the organic waste/ feed stock

is subjected to microbial decomposition yielding methane, carbon dioxide and water.

Although this process was known to occur naturally in the environment, it has been

developed further by science in the past hundred years as a sustainable source of

energy and of plant nutrients. Thus, modern day anaerobic digestion in a anaerobic

digester/biogas plant may be defined as the engineered methanogenic anaerobic

decomposition of organic matter (Khoiyangbam et al, 2011). Thus, it is the

consequence of successive metabolic interactions between various groups of

microorganisms which can be categorized into three stages:


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Table 1: Stages in Anaerobic digestion process

Stage Process Description Conversions/Principal products

Hydrolysis/liquefaction First group of fermentive bacteria secretes enzymes,

which converts the organic

matter into a simpler form

such as cellulose into sugars

and amino acids.

Lipids→ Fatty AcidsPolysaccharides→ Monosaccharides

Protein→ Amino Acid

Acidogenesis Product of first stage utilized

by acetogenic bacteria intoorganic acids, higher volatile

fatty acids and hydrogen.

Acetic acid (CH3COOH),

Propionic acid (CH3CH2COOH),Butyric acid (CH3CH2CH2COOH

Ethanol (C2H5OH).

Methanogenesis The third group of

methanogenic bacteria finally

converts H2, CO2, and

acetate, to methane (CH4).

CH3COOH→ CH4 + CO2

(acetic acid) (methane

(carbon dioxide)

2C2H5OH + CO2 →

CH+2CH3COOH

(ethanol)

CO2 + 4H2→ CH4 + 2H2O

(hydrogen) (water)


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F eedstock

A biogas system works with many types of feedstock that is of organic material

including sewage, manure, forestry waste, agricultural waste. This study will beconcentrating on the organic fraction of waste from residential, commercial and

industrial sources in urban areas as a feedstock for AD. Examples of this include:

food wastes from homes, businesses, market areas and food processing companies

that are dumped in landfills and horticultural waste such as grass, leaves and grass

clippings which are generally composted or sent to landfills

Biogas utilization

Storage The variance of the production and consumption hours and also the point of

production and consumption make for the need of different gas storage mechanisms

for the use of biogas. The different options are: High pressure tanks (200-300 bar): These require high technological input

and investment and common uses are as a tractor fuel. Medium pressure gas tanks (10-20 bar): Special safety measures need to be

taken in this range and their benefits include its relatively small magnitude. Low Pressure holders wet or dry type (up to 50 mbar): Most gas used for

storage in biogas systems are of the low pressure type such as those of

community based biogas plants. The main types are: water sealed

membranous, gas cushions.

Since gas holders are relatively expensive, simpler methods used for storage such as

the gas balloon-a self sealing plastic bag- and a gas tight plastic bell. Gas stored in

bags need to be maintained at a constant pressure and safety measures to guard

against flaming.


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BottlingThe limiting factors in bottling biogas include its high cost that is similar to LPG.

(Khoiyangbam et al, 2011). Also biogas has a high critical pressure and temperature

i.e. maximum pressure/temperature at which a compound can exist as a liquid (46

atmospheres and -82.5 degree C respectively). This factor can significantly increasethe cost of a pipeline.

DistributionThe layout of the distribution system will depend on the distance between the

digester and different points of consumption. In community biogas plants, the

delivery pressure decreases with distance. When it exceeds 2 km, it often needs

booster pumps to support a stable flame. Pipes are generally made of GI, Polyvinyl

Chloride (PVC) or high density polyethylene (HDP) plastic.

UtilizationBiogas can be used as a fuel in the kitchen, for lighting or for operating internal

combustion engines. If available in sufficient quantities, it can also be used as a fuel

source by small scale industries.

Cooking

It can serve as a clean and efficient fuel source for cooking through biogas burners.

Gas consumption for cooking and lighting is 0.34-0.41 m3/capita/day and 0.15

m3/h/100 candle power respectively. Thus a family of six members uses

approximately 2.9 m3/day of biogas. (Khoiyangbam et al, 2011).

Lighting

It is also a clean source of home lighting. Biogas lamps are similar to burners with

the addition of a mantle. Low gas pressure means a lower light intensity but high

pressure can cause lower life of the mantle. Electric lighting can also be provided

through biogas generated power and it consumes less gas but biogas lamps and isalso brighter and more reliable. But gas lamps are much cheaper in terms of cost per

delivered candle power. Roughly 0.13 m3/h is needed to light a gas lamp and a little

lesser for electric lighting.


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Working of Engine

Both stationary and mobile engines can be run by that can supply motive power and

pump water, drive machinery or generate electricity. It can be used as a fuel for bothspark ignition engines (petrol) and compressed ignition engines (diesel).It can also

run on all types of stationary diesel engines as a dual-fuel system with 80% biogas

usage. While petrol engines can be run on 100% biogas. Advantages of using biogas

in fuel engines include clean combustion (as it is a clean fuel) and lesser engine oil

contamination. 245 liters of gas is required per horsepower per hour for an average

engine. For a 5 HP engine, 18 m3 of the gas is required per day. Larger engines have

greater conversion efficiencies. (Khoiyangbam et al, 2011).

Vehicle

Biogas offers a first-rate starting for vehicles in comparison to petrol which needs

vaporization first. Less air pollution is also created. But one of the biggest problems

is the limited amount of biogas that can be carried in cylinders of biogas driven

vehicles. Biogas for vehicular use also needs to be freed from carbon dioxide and

compressed into high pressure engines.

Biogas as an energy source

Biogas produced through anaerobic digestion has the following composition:

Table 2: Composition and energy value of biogas (Khoiyangbam et al, 2011).

Property Methane Carbon

Dioxide

Hydrogen

Sulphide

H2 Biogas

% by

Volume

54-80% 20-45% 1/10 0.0-10 100

Energy

Value

(kcal/l)

9.0 - - 2.9 5.4


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Table 4: Cost comparison to other sources of power (Ravindranath and Balachandra,2009)

Table 5 : Cost comparison to kerosene stove (Ravindranath and Balachandra, 2009)

Benefits of Anaerobic Digestion The prime benefits of anaerobic digestion of MSW are to divert waste away from

landfills and mitigation of climate change while energy production is an added,

secondary benefit that enhances the attractiveness of this technology. These are as

elaborated below:

MSW M anagement

The total MSW generated in urban India currently is estimated to be 68.8 million

tons per year (TPY), which is a 50% increase in MSW generated since 2001. This is

projected to increase to 160.5 million TPY by 2041 at the current rate of economic

expansion. Of this MSW generated, 51% is composed of organics, 17.5% recyclables

(paper, plastic, metal, glass) and 31% of inert material. Its calorific value is 7.3

MJ/kg (1745 kcal/kg) (Annepu, 2012). Most of the waste collected is disposed on

open lands or unsanitary landfills. Many municipalities have not yet identified

Total Life Cycle Cost (Rs/

kWh)

Unit cost of energy (Rs/

kWh)

Biogas + diesel 183170 (4482) 5.15 (0.126)

Diesel 523140 (12800) 14.44 (0.353)

Grid electricity (coal

based)

174310 (4265) 3.25 (0.80)

Total Life Cycle Cost (Rs/

GJ of heat output)

Unit cost of energy (Rs/GJ

of heat output)

Biogas plant stoves 2469.7 (60.43) 272.07(6.66)

Kerosene stove 1743.1(42.65) 459.82 (11.25)


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landfill sites in accordance with MSW rules 2000 or have exhausted the space in

existing landfills and do not have more space to acquire additional land. Such a strain

on land and lack of space distorts MSW collection efficiency. Unsanitary land

filling pollutes surface and ground water and causes greenhouse gas emissions. Pests

and other vectors feeding on this waste are a cause for disease. Inhalation of bioaerosols and of smoke and fumes produced by open burning of waste are also a cause

of public health problems. By diverting the organic wastes to separate facilities,

considerable and scarce land area is saved while also reducing the problem of odor

and air, water and soil pollution.

Climate Change M iti gation

Lack of oxygen or near anoxic conditions in landfills produce methane through

anaerobic digestion of the organic waste. Due to these anaerobic reactions, landfills

emit methane while they are in use and even several years after their closure.

Methane has 21 times more global warming potential from CO2 and causes global

warming if released into the atmosphere. Solid waste management is the third largest

emitter of anthropogenic methane in the world (3% of global GHG emissions).In

India it is the second largest and the largest among those activities that do not have

any economic value addition (6% of 2.4 Giga tons of CO2 equivalents generated by

India) (Annepu, 2012). An insignificant portion of methane emissions from landfills

is presently captured and the rest is discharged into the atmosphere; thus the potentialof capturing this from these sites for control of GHG and averting climate change is

huge. In other words, by implementing AD technology at the full scale waste-to-

energy capacity, emissions from landfill waste can be mitigated in a major way.

Decentral ized Vs Central ized waste Treatment

The centralized arrangements of managing waste include using landfill sites,developing future sites, waste-to-energy plants and centralized large waste-to-

compost facilities. All these options have some significant drawbacks: They do not differentiate between the waste compositions arising out of

various localities within a city.


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They often capital and land intensive. It is projected that the land

requirements for disposing MSW will rise to 1400 sq km by 2047 (Annepu,

2012). Diverting such an amount of space in land scarce urban areas will

represent high opportunity costs.

Centralized arrangements do not leave scope for community involvement

(through segregation, recycling etc) and its resulting innovations. Informal

waste pickers and recyclers may be denied access to recyclables in the waste

stream in centralized systems (such as incineration) and hence it represents a

threat to their livelihoods. (G Asher and Gandhi, 2008)

These arrangements may be viewed as just shifting the problem from wastesource to the disposal sites. It also means high transportation costs for

moving wastes to the disposal sites.

Decentralized community-based waste management arrangements such as anaerobic

digestion technology do not have these drawbacks as they treat waste close to the

place of origin and they also encourage civic responsibility, community involvement

and innovations.

Limitations of AD

En vironmental Sensitivi ties

The anaerobic digestion process can be said to be inefficient as the bacteria in

anaerobic digestion are not as good as their aerobic counterparts in extracting energy.

The anaerobic bacteria are able to access only 5-10% of the energy contained in the

methane for use to grow as opposed to 50% for the corresponding aerobic process

(Stuart,n.d). Due to this, they are slower to grow and more vulnerable to changingconditions. It is thus very essential to maintain a suitable environment in the digester.

Some of the parameters that need to be carefully controlled for optimum

performance of the process are: PH: The ph of the digester should be kept neutral.


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effectively handle a plant. This expertise may be found to be lacking in developing

countries and training or employing qualified people may form a large part of the

initial capital costs.

H ydrogen Sul phide Production

Sulphur present in organic wastes causes the production of hydrogen sulphide in the

digestion process which can then become a part of the biogas. Hydrogen sulphide is

a highly corrosive substance that can adversely affect the plant components such as

the walls of the digester.

H eavy M etals

The feedstock may very often contain certain heavy metals or POPs. Thus it has to

be ensured that the waste fed into the digester has undergone proper segregation as

these heavy metals cannot be broken down in the digestion process.

Economic Viabili ty

Anaerobic digestion as a commercial level technology is still in a phase of

development and may not yet be viable purely as a source of renewable energy.Other benefits derived from the process such as proceeds from sale of organic

fertilizer, savings on chemical fertilizer, optimum inorganic nutrient recycle etc must

be made use of for financial viability of setting up and running the plant.

AD technology around the world 3.6.1 Eu rope

Europe has been a world leader in adoption of Anaerobic Digestion of municipalsolid waste since the introduction of the technology in the 1990s. Almost 200

biomethanation plants for MSW were in operation up to 2010, spread over 17

countries with a total waste treatment capacity of 6 million TPY. Germany is the

world leader in this sphere with more than 1.7 million TPY of installed capacity

followed by Spain (1.5 million TPY) and France (80,000 TPY). Spain, Belgium,


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Holland, Switzerland, and Germany are among the larger European countries having

the highest per capita anaerobic digestion capacities. About 10% of organic waste in

Spain is treated in Anaerobic Digesters. In 2009, the biogas production of EU

countries (25) was equivalent to 16.692 billion m3 biogas, of them 35.96% from

landfill, 12% from municipal and industrial sludge anaerobic digestion and 52%from scattered farm, municipal solid waste and centralized co-fermentation biogas

projects.

During 2006-2009 EU biogas production has increased by 70.37%mainly

benefited from the increased agricultural biogas projects and municipal solid waste

biogas projects. The drivers underlying this growth include: Firstly a series of

landmark directives such as The Landfill Directive 1999 that set targets for

progressively reducing the waste going to landfills. The Renewable Energy Directive2001 also sets targets for EU member states for the amount of electricity to be

generated from renewable. Secondly this technique became popular in comparison to

others such as incineration, pyrolisis, gasification due to poor public acceptance,

high development costs. Also, source separation and segregation of the organic

fraction of solid waste is a practice actively practiced and encouraged in these

countries.

UK

Biogas recovery is mainly through landfill wastes here. The UK Green Certification

System (Renewable Obligation Certification System) requiring increased renewable

energy power generation from all power suppliers greatly pushed forward investment

in biogas power. The biomass power generation was 6,143 GW/h as of 2009

accounting for 24.7% of renewable power generation, second only to wind power.

The government also provides support for R&D, demonstration projects for grid

power generation from biogas. Strict landfill taxes and standards have also beenimposed, increasing the cost of waste disposal.

Germany

Germany has the largest installed capacity with over 4,000 biogas plants 1.5 GW of

biogas based electricity. The average electrical capacity of each plant is 400-800 kW.


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Most of the plants are of large scale capacity for treatment of farm waste, MSW, or

organic industrial waste. Biogas thus is a important source of generating electricity

or for space heating. The driving forces are mainly preferential policies and

incentives. The promulgation of “Grid Integration of Power” in 1990, and the

“Renewable Energy Act” in 2000 and support programmes for biogas powergeneration created a conducive environment for all types of biogas projects from

small farm based digesters to large scale industrial projects while also increasing

income potential from grid based power generation.

China

Biomethanation has been receiving support here ever since the ‘Great Leap Forward’

movement in the1950’s.Tthe energy crisis of the 70’s also gave a renewed push with

a phenomenal increase from less than a million to 7 million plants in a decade. China

today has the maximum number of individual biogas plants and world’s largest

biogas programme. Main feedstock is animal waste followed by crop residues and

vegetable wastes. While gas from the smaller sized plants are used for lighting and

cooking, the larger ones are used for electricity, powering agricultural machinery and

pumping irrigation water. In urban areas it is run by distilleries, waste disposal and

night soil treatment units.

More than 25 million Chinese households have biogas plants installed. 2492medium and large scale digesters were installed in poultry and livestock farms. The

substantial subsidy offered by the government explains the widespread use of this

technology. Their renewable energy support programme has five basic components-

market development and protection, technical support, price support and cost

sharing, financial support and resource utilization. This programme encompasses

support to biogas energy also. Various measures have been taken to promote

manufacturing of biogas plants on an industrial level. Several private companies arecoming up with innovative designs to bring down costs, simplify construction and

minimize technical defects.

Mianzhu city treats 98% of municipal sewage through digesters with a total capacity

of 10,000 m 3 . This treated water even reaches national discharge standards. One of


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the largest alcohol factories, Hongzhi Alcohol Corporation has commercialized a

service to treat industrial wastewater and sewage through AD and it is demanded for

by industry and households alike. It has also set up a large biogas plant capable of

producing 7 million kilowatts of electricity an hour.

Australia

Here too, the landfill reduction policies of the government and Sydney city planners

lead to the construction of a 170,000 MT/y (187,000 tons/y) AD facility in 2003 with

2.2 MW of electrical generating capacity. A 35,000 MT/y (38,500 tons/y) wet

digestion facility built also began digesting commercial waste and wastewater

treatment sludge in Sydney in 2003. Waste- to- Gas Plants are also being set up in

many parts of Western Australia such as Perth and Pilbara.

Various organizations and mechanisms exist in order to provide grants for biogas

plant construction, such as Low Carbon Australia, Clean Energy Finance

Corporation and the Australian government’s Clean Technology Investment

Program. The Carbon Pricing Mechanism of the government aimed at the largest

polluters also targeted landfills that have net GHG emissions.

Nepal

They have also shown a keen interest in biomethanation following the energy crisis

of the 70’s. Domestic sector is the primary consumer of energy in Nepal and

according to estimates there are 27.7 million tones of cattle waste generated per year

that can be used to meet the fuel needs of over 4,00,000 households. It is also viewed

here as a solution to the increasing deforestation problem and as a source offertilizer. Feedstock for the plants is mainly cattle dung and under the aegis of the

Department of Agriculture, Agriculture Co-operatives and the private sector,

thousands of biogas plants have been installed in all districts, and this is the outcome

of planned support programmes and incentives. Operational scale of these plants are

also good, with 85-90% of them functional.


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CHAPTER 4

Status of AD technology in India

The process of anaerobic digestion has been practiced for decades in developingcountries. The first anaerobic digestion plant in Asia for generating methane from

organic waste was installed at Matinga Leper Asylum in Mumbai in1897. Like most

developing countries, India’s biogas support programmes were focused on family

sized digesters for rural families with cattle where animal manure and human faeces

could be used as feedstock in order to provide people with biogas for cooking,

reduce firewood consumption and deforestation and indoor air pollution and improve

soil fertility. The process of penetration of family sized digesters began with theimplementation of the National Project on Biogas Development in 1981 now

renamed as the National Biogas and Manure Management Programme.

After more than 25 years of putting into practice and technical improvements, biogas

technology is still being explored as a reliable renewable energy source and a

replacement to fossil fuels.Today, India has approximately 4 million installed AD

systems, most of them of family size.

While centralized high-technology plants for anaerobic digestion of organic waste is

well established in developed nations, appropriate low-technology options are still

lacking in developing nations (Vogelli et al 2014) .Thus, anaerobic digestion as a

waste treatment alternative for urban settings, primarily processing kitchen or market

waste, still plays a minor role and thus there is little available data on the spread of

this technology, technical, operational and financial feasibility.

Biomethanation of organic municipal wastes as a centralized treatment option beganto be implemented in many cities in India from the 1990s along with other waste to

energy technologies. The current installed capacity of biogas based power systems in

India are as shown:


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Table 6: Installed capacity of waste to energy and biogas based power systems

SECTOR FINANCIAL YEAR 2014-15 CUMULATIVE

ACHEIVEMENT

TARGET ACHEIVEMENT (As on 31.03.2015)GRID INTERACTIVE

POWER (IN MW)

Waste to Power 20.00 8.50 115.08

OFF-GRID POWER (IN

MW)

Waste to Energy 10.00 21.78 154.47

Biogas Based EnergySystem

0.00 0.30 0.47

Table 7 : Statewide Installed capacity of power from waste to energy

States/UTs Waste to Energy (As on

31.03.2010) in MW

Waste to Energy (As on

31.03.2011) in MW

Andhra Pradesh 4.95 6.55Gujarat 8.4 10.79

Karnataka 3 3

Madhya

Pradesh

0.1 0.11

Maharashtra 5.11 6.81

Orrisa 0.02 0.02

Punjab 1.58 1.81

Tamil Nadu 4.73 6.14

Uttar Pradesh 17.31 24.91

Uttarakhand 1.52 3.07

Total 46.72 70.54


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Implementation strategies for biomethanation in India

I nstituti onal arr angement

Clean energy development is a priority area of the Indian Government. The Ministry

of Renewable Energy is the primary agency involved in developing alternativeenergy based technologies. The Ministry’s programs are implemented through the

respective state renewable energy agencies and state nodal departments.

An advisory committee on R&D assesses proposals from industry, researchers and

entrepreneurs. It also provides funding to various research institutions with the aim

of reducing costs and improving efficiency and reliability of the systems.

Indian Renewable Energy Development Agency (IREDA) is the financial wing of

the MNRE which provides subsidized financing for projects in the sector so as to

promote its accelerated use and market development through commercialization. It

also attracts funds from various multilateral agencies..

Programme formulation and implementation

Dissemination of medium and large size biogas plants are being taken up through

various schemes such as:

Programme on Energy Recovery from Urban and Industrial Wastes

An MNRE Programme set up in 1995 with the following objectives:

To promote set up of projects for recovery of energy from wastes in the

Urban and Industrial sectors. Creation of conducive environment for development and dissemination of

energy recovery from waste through appropriate fiscal and financial regimes. Development and demonstration of new technologies for energy recovery

from wastes through R&D projects and set up of pilot plants.

This scheme is implemented through state nodal agencies and is applicable to private

and public entrepreneurs and organizations and non-governmental organizations for


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setting up of waste to energy projects on the basis of BOO,BOOT, BOT and BOLT

models.

Achievements:

Projects for energy recovery from Municipal Solid Wastes with an

aggregate capacity of 17.6 MW at Hyderabad, Vijayawada and

Lucknow. 1 MW project based on cattle manure at Haebowal, Ludhiana; 0.5 MW project for generation of power from biogas at sewage

treatment plant at Surat. 150 kW plant for vegetable market and slaughterhouse wastes at

Vijayawada. 65 projects for biomethanation of industrial wastes with a total

capacity of 86 MW

Accelerated Programme on Energy Recovery fr om Ur ban Wastes

An MNRE project set up in 2005 (still in force) with the following objectives: Acceleration of promotion of projects set up in the waste to energy sphere

Creation of conducive environment for development and dissemination ofenergy recovery from waste through appropriate fiscal and financial regimes.

Harnessing the available potential of MSW- to- energy by the Year 2017.

Project Development Assistance of Rs 10 lakh per project can be provided for this

activity involving the following:

Analysis of MSW and assessment of quantity

Identification of project site Preparation of MSW collection and transportation plan Finalization of tie-up with the ULBs for land lease and supply of waste Finalisation of power purchase agreement Development of a bankable project with Feasibility Report and the DPR Preparation of the bid document for inviting bids for viability gap funding;


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Firming up of means of project finance Assistance in entire process of bidding Obtaining all statutory clearances for the projects Providing assistance and supervision during execution and commissioning

Demonstration of Integrated Technology Package on Biogas Fertilizer Plants

(BGFP) for Generation, Purification/Enrichment, Bottling and Piped

Distribution of Biogas.

It is a ministry initiative that aims to demonstrate an Integrated Technology-

package for entrepreneurs who set up biogas-fertilizer plants (BGFP) ofmedium size. The biogas generated may be purified/enriched, bottled or

distributed through pipes. Such plants may be used to meet requirements for

stationary and motive power, cooling, refrigeration and electricity needs in

addition to cooking and heating requirements.Central financial assistance will

be provided for projects in an entrepreneurial made established under a

BOOT basis.

F in ancial assistanceBi ogas based distr ibuted /Gri d power generation programme: Centr al f in ancial

assistance

Table 8: Financial Assistance for grid power generation from biogas

Power Generating Capacity CFA limited to the ceiling or

40% of the cost of the system

3-20KW 40,000 per kW

>20 kW to 100 kW 35,000 per kW

>100 W to 250 kW 30,000 per kW


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1,100-5000 40%

5,100-10,000 35%

10,100-20,000 and above 30%

Policy makin g and planni ng

El ectri city actBiomass based power systems come under the purview of the Electricity Act.

National Electricity Policy (2005) and the Integrated Energy Policy (2005) provided

the required enabling environment for the promotion of electrification to the entire

country.Some of the provisions contained in this act for promotion of renewable energy

projects including biogas based projects are given below: Open access to grid Preferential tariffs by State Electricity Regulatory Commissions Targets for Renewable Energy power Captive generation decontrolled

The National Electricity Policy and the Integrated Energy Policy support

decentralized distributed generation facilities (either conventional or non-

conventional methods of electricity generation, whichever is more suitable and

economical) together with a local distribution network, wherever grid-based

electrification is not feasible.

The M un icipal Soli d Wastes (M anagement and H andli ng) Rul es, 2000

The Ministry has issued the Municipal Solid Wastes (Management and Handling)

Rules, 2000, which provides for collection, storage, segregation, transportation,

processing and disposal of solid wastes. The Rules state that all urban local bodies

are responsible for the municipal solid waste in its respective municipality whereas,

the Department of Urban Development in the State has overall responsibility for

enforcement of these rules in metropolitan cities.


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It mandates that land filling should be restricted to non-biodegradable and inert

waste which is neither suitable for recycling nor for biological processing. Land

filling shall be carried out for residues of waste processing facilities as well as pre-

processing rejects from waste processing facilities. Landfilling of mixed waste shall

be avoided unless the same is found unsuitable for waste processing. These Rulesfurther stipulate that all biodegradable waste such as waste from slaughter houses,

meat, fish and vegetables, shall not be land filled but be treated appropriately and

used. These Rules however do not specify the end use of the treated bio waste nor

the technology to be used.

The MSW rules (2000) define municipal solid waste as commercial and residential

waste generated in municipal or notified areas in either solid or semi-solid form

excluding industrial hazardous waste; e-waste and including treated bio-medical

waste.

SCOPE OF BIOMETHANATION IN INDIA

62 million tonnes of waste are estimated to be generated annually by the current

number of 377 million people residing in urban areas. Of this, the municipal

authorities dump more than 80% at dump yards in unhygienic conditions leading to

health and environmental problems. CPCB estimates suggest that only 68% of the

waste generated in the country is collected of which 28% is treated. This means that

a mere 19% of waste generated in the country is treated. Besides other methods of

generating energy from this waste, there is an untapped potential of generating 1.3

million cubic meter of biogas per day which translates into 72 MW of electricity.

“The existing policies, p rogrammes and management structure do not adequately

address the imminent challenge of managing this waste which is projected to be 165million tonnes by 2031 and 436 million tonnes by 2050 (Planning commission

2014)”. MSW management is a challenge from the organizational, technological and

economic point of view. Urban waste management must address the concerns of

public health and environmental safety before anything else. Also proposed solutions


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to MSW management have to meet the criteria of financial viability and community

and institutional acceptance.

A major fraction of urban MSW in India is organic matter (51%). Recyclables are

17.5 % of the MSW and the rest 31% is inert waste. The average calorific value ofurban MSW is 7.3 MJ/kg (1,751 Kcal/kg) and the average moisture content is 47%

(Annepu, 2012) .The large fraction of organic matter in the waste makes it suitable

for aerobic and anaerobic digestion. Significant recyclables percentage after informal

recycling suggests that efficiency of existing systems should be increased. Recycling

and composting efficiency are greatly reduced due to the general absence of source

separation. Absence of source separation also strikes centralized aerobic or anaerobic

digestion processes off the list.

Table 11: Population growth and impact on overall waste generation

Year Population

(Millions)

Per Capita waste generation

(gms)

Total waste

generation

Thousand tons/year

2001 197,3 439 3163

2011 260,1 498 473

2021 342,8 569 7115

2031 451,8 649 10701

2036 518,6 693 13124

2041 595,4 741 16096

Other than anaerobic digestion, there are various techniques for converting the

organic component of waste into energy, such as WTE combustion and RDF.

Table 12: The potential of energy generation from MSW

Period MSW Generated

(TPD)

Power

Generation

Potential (MW)

2002 97.174 1.638


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2007 130.927 2.266

2012 189.986 3.276

2017 265.834 4.566

Key drivers for Waste to Energy Projects

Globally, there is a rising interest in waste to energy projects (of which bio

methanation is one of the preferred technologies) due to advancement in technology

and growing environmental regulations.

Though waste to energy applications is relatively nascent in India, it has enormous

potential as an energy source, business opportunity and a sustainable wastemanagement option. The enabling policy environment as well as the benefits of the

project forms some of the drivers of waste to energy

I ncreasin g Quanti ty of Waste materi al

The rise in quantity of waste generated ,projected to increase to 160.5 million TPY

by 2041, fuelled by rise in economic growth, gross domestic product, and consumer

spending has necessitated the need for better management of waste, in the form of

alternative methods of waste treatment such as biomethanation.

Declin in g space for landfi ll s

Land space is increasingly scarce in metropolitan areas and finding space for

landfill sites will become a problem. Also, due to political and community demands

or expiry of the lifetime of current landfills, existing landfill sites are under pressure

to be closed down

En ergy Avail abili ty: Demand and Supply Gap

Projects is one option that can help decrease this gap and reduce dependence on

fossil fuel based energy sources or grid based supply.The price volatility being

observed in the prices of natural gas or fossil fuel has forced countries to focus on

renewable energy options.

Policy Envir onment


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In order to control urban pollution the government has introduces regulations and

norms for industrial pollution control as well as for management of municipal solid

waste and these are to be implemented by the central and state pollution control

boards. Also, India’s participation in international conventions such as the UNFCC

has brought attention towards the rise in carbon emissions at present and projectedfor India.

F in ancial Support

Due to the capital intensive nature of Waste to Energy projects, they can be

designed, set up and/or operated by a private entrepreneurs/firms,

industry/institution, municipal corporation, urban local body or by a waste

management service provider either on commission basis or on BOOT basis.

The range of incentives include subsidies on interest rates and capital costs for

demonstration projects, 100% accelerated depreciation and sales and excise taxes

exemption .Many government as well as private agencies provide financial

assistance for these: Ministries like MNRE and MoEF, financial institutions like

IREDA, NABARD, state financial corporations and commercial banks. International

agencies such as the World Bank, UNDP, IFC, and ADB also sponsor waste-to-

energy projects.

Parti cipation of pri vate companies

Currently, private sector firms are the only players in the waste to energy market.Given the right subsidies, incentives and support by government, municipalities and

civil society; they have the potential to fuel the market growth in this sphere.

Other Economic Benefi ts

Industrial Waste to Energy conversion have the opportunity to be developed in the

CDM space that would yield incentives such as higher return on investment and

lower payback period.

Case studiesIn this section an attempt has been made to study and analyze some of the live

examples of solid waste management through anaerobic digestion using small to

medium size biogas plants


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Soli d Waste Management of M arket Waste Usin g An aerobic Digestion in

Thir uvananth apuram, Kerala (H eeb, 2009)

To comply with the Municipal Solid Waste (Handling and Management) Rules 2000

many urban local bodies decided to treat their organic waste in bio gas plants and use

the biogas produced for various socially useful purposes.The Sreekaryam Grama Municipality in Thiruvananthapuram, the capital of Kerala is

one such local body which decided to treat the organic waste generated in the

municipality in a bio gas plant. The Sreekaryam biogas plant has been constructed to

primarily treat the bio waste generated by the local fish market which is one of the

biggest fish markets of Thiruvananthapuram. Therefore, the feedstock basically

consists of fish waste, although occasionally some small quantities of vegetable and

fruit waste are also added.

Gas Production

While the digester feeding capacity of the Sreekaryam bio gas plant is 250 kg/day,

the actual average load is 85.5 kg/day.

Table 13: Gas Production and quality

Parameter Average Value

Daily gas production(cu.m/d) 4.97

Average CH4 content (%) 66.8

Average CO2 content (%) 27.4

Utilization of Biogas

The biogas that is produced in the Sreekaryam fish market plant is first scrubbed to

get rid of the Hydrogen Sulphide by dissolving it water and oxidizing it. After

scrubbing the gas it is used in a custom-made 5kW bio gas generator to produceelectricity to light up the fish market and the surrounding areas. However, since the

average daily gas production is higher than the requirement for electricity

production, the excess gas is sometimes flared.

Quality of Effluents


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The effluent of the Sreekaryam fish market biogas plant is a dark and homogenous

liquid. The total nitrogen, ammonium, total phosphorous and ortho-phosphate values

of the effluent are high. Furthermore, the ammonia smell could negatively affect

general acceptance of the biogas plant.

One of the drawbacks of the Sreekaryam fish market biogas plant is that the effluentof its digester is not used as fertilizer. It is pumped into the storage tank and is used

to flush the feedstock into the digester. The excess slurry is discharged from the

effluent tank into the municipal drain.

Socio-economic Aspects

The cost of construction, operation and maintenance of a biogas plant of this size for

disposal of bio waste by a municipality is tabulated below:-

Table 14: Costs of plant operation

Investment Cost in Rs.

Material 600 000

Labor 900 000

Total 1500000

Operational & Maintenance Costs

Annual Operational Expenses 112 500

Annual Maintenance Contract 75000-112500

It may be seen from the figures above that the initial investment required for such a

plant is quite substantial. More importantly, the annual costs for operation and

maintenance add up to 15% of the investment costs.

Discussion

While this type of biogas plant may be ideal for processing of bio waste of a market

like the Sreekaryam fish market, there are some technical challenges like the high proportion of nitrogen in fish waste which need to be addressed. Some of the counter

measures that can be adopted are:- Adding fresh water to the feedstock/slurry. Adding more high carbon waste such as vegetable and fruit waste


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The feedstock that is being used in these prison biogas pants is human faeces and

limited quantities of kitchen waste. It has been estimated that the average daily

output of human waste per adult person in Nepal is approximately 0.4 kg and 1.5 L

of urine (Karki et al., 2005). The average use of water for cleaning, flushing and

washing of toilets is about 2 to 4L per person per day. It was estimated that the totalfeedstock, excluding kitchen waste, produced in a prison with about 100 prisoners is

approximately 520L and the active slurry volume, in the digester with a capacity of

10 cubic meters, is about 7500L.

Quality and Quanti ty of Gas

While the gas production in digester varied according to the quality and quantity of

the feedstock, it was observed that the average gas production in a digester using

only human waste as feedstock was approximately 30L per person per day. When the

quality of the feedstock was improved by adding kitchen waste, the gas production

increased substantially to approximately 60L per person per day. The methane (CH4)

content of the gas varied from 57% to 78% and the Carbon Dioxide (CO2) content

varied from 17% to 34%.

Uti li zation of Gas

The biogas that was produced in the prison plants was utilized for regulated

community cooking and unregulated individual cooking. The use of biogas for

cooking effected substantial savings on the purchase of conventional fuel for

cooking.

EffluentsAnalysis of the effluents revealed that it had acceptable concentration of E. Coli and

little or no presence of helminth eggs. Therefore the effluents are fit for restricted

irrigation as per WHO guidelines. However the effluents are not bing used as

fertilizer due to local circumstances and psychological barriers.


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Socio-economic Aspects

As the economic benefit of using biogas is directly related to the volume and

quality of biogas produced, it was determined that in prisons where kitchen waste

was added to the feedstock, the saving effected on the expenditure on conventional

cooking fuels was 41%. In other jails, where only human waste was used asfeedstock, the saving effected was between 17% and 22%. Thus, depending on the

quality of feedstock, the number of prisoners and the number of biogas plants in a

prison, the plants can pay back the cost of installation in 2 to 5 years time.

With regard to the social aspects, it was seen that a overwhelming majority of the

prisoners supported the installation of biogas plants in prisons as it improved the

living conditions by reducing the smoke in the kitchen and by improving the

hygienic conditions. However, there was some skepticism regarding use of human

waste to make cooking fuel. It was feared that the taste of food cooked with biogas

may be poor and that some diseases may be transmitted through food cooked using

biogas. These apprehensions, however, were short lived and soon there was wide-

ranging acceptance of “biogas food” among inmates of Nepalese prisons.

Discussion

The experiment of installing biogas plants in Nepalese prisons to utilize human and

kitchen waste to produce cooking fuel has been undoubtedly a success story that can be replicated in institutional facilities in other developing countries.


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Based on the above criteria, biomethanation technology for organic solid wastes

based on medium and large scale anaerobic digesters can be said to be at a take-off

phase of development.

Interview procedure

Sample

Expert interviewees were selected for a balanced sample of various actors in the TIS

system and these insights were used for an overview of the status of medium and

large scale biomethanation of MSW in India.

Table 16: Interviewee Sample

Interviewee Type Details Number of interviews

Entrepreneur Manager of a large waste

to energy company.

1

Government Official Official at IREDA 1

Academician Professors at Research

Institutions who areexperts in the field of bio -

energy.

2

Independent Consultant Honorary Chairman of an

Industrial association for

Biogas

1

Potential Investor DGM, Catering at IRCTC 1

Data coll ection

A semi structured data questionnaire format was chosen, which contained various

key pointers to be enquired from all categories of actors/interviewees.The

questionnaire was designed such that questions relevant to each function category in


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the TIS literature would be answered. All interviews were conducted personally ,

through face-to-face communication, phone or via e-mail.

Data anal ysis

The interview notes were transcribed and key takeaways from each are detailed in

the next section in accordance with the TIS function categories, according to their

relevance.

Results

F 1 En trepreneur ial Activities: Entrepreneurial activities are relevant because their

activities aim to prove the usefulness of any innovation or technology, its

commercial and technical viability, i.e through new models, demonstration projects

or through business ventures.

Key Takeaways: All the interviewees admitted that entrepreneurial activity in the bio

methanation sector is still very limited. For industrial wastes such as those generated

in sugar and distillery industries and for wastewater, deployment of anaerobic

digesters anaerobic digesters is an established practice. But bio methanation for

SWM is still a new and emerging concept (Independent Consultant). There is also a

need for more industry academia co-ordination in this regard (Academician).Overall, “The potential of medium and large scale biogas plants particular in urban

and industrial areas is by far underdeveloped despite the fact that biogas holds

particular importance for the rapid economical growth of India”, as summed up by

the entrepreneur.

F2 Knowledge Development: These relate to activities aimed at learning and

development. It not only includes R&D in the basic science (learning-by-searching) but also activities in a practical context among the markets, networks and users

(learning-by-doing).

Key takeaways: Many institutions engaged in the field of research in the area of

biomethanation such as the IITs, IISC Bangalore, BARC Bombay, IARI etc. They


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take up lab scale/pilot work and have also come up with various digester models for

various substrates such as wastewater, cattle dung, agro waste etc. But in the field of

waste-to-energy (WTE) in the field of MSW, there is a lack of technical expertise.

Also, even though there are enough technologies present , there is still a need felt for

indigenously developed engineering equipment such as large sized engines forconverting biogas to electricity (Independent Consultant). Foreign technologies and

equipment are also imported for medium and large scale digesters but their flipside is

that they are expensive and need to be adapted a lot to suit Indian conditions (All

interviewees).

F 3 Networks and knowledge dif fu sion : The core of the organization structure in a

TIS system lies in networks, where actors of different backgrounds interact.

Knowledge diffusion can occur with industry-academia collaboration, meetings like

workshops and conferences, promotional activities by industrial associations etc.

There are no associations existing exclusively for the promotion of bio methanation

of MSW in India. There are only two professional associations existing in the

country, namely the Indian Biogas Association (IBA) and the Biogas Forum of India

(BFI) to promote and support the activities of operators, manufacturers, planners of

biogas plants and of scientists and researchers. They undertake conferences and

workshops, publish newsletters, promote collaborations with international know howand also perform policy advocacy roles. The MNRE also publishes two bimonthly

magazines on renewable energy and in which biogas projects are also featured. For

submitting project proposals and applying for financial assistance, there exists

IREDA and the respective State Renewable Energy Development Agencies. Also, as

the number of ESCOs in this field is limited, there is not an adequate transmission of

information regarding the need and benefits of bio methanation projects, not just in

terms of environmental benefits but also in terms of financial viability and profitability.

F 4 Guidance of th e search: This includes the vision, expectations and requirements

of various actors in the TIS. These should be aligned across all the players or actors

in a technological field as resources are limited. For e.g. there should be a clear


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(Independent consultant). Although waste disposal rules and norms (MSW rules,

CPCB norms) in urban areas are in place their implementation and monitoring

remain lacking. Standards and certifications such as the IS standard do exist for

biogas plants.

F 6. Resource mobil ization: Adequate financial, material and human capital need to

be deployed in order to set the technology up and running and to make it viable.

There is a need for investment and subsidies, research facilities, physical

infrastructure etc and their lack or absence can form a barrier to expansion.

Financial support from government sector may be adequate but from private banks it

is a major problem (Independent Consultant).For developing human capital, BTDCs

have been set up by the government in various universities for training, monitoring

and evaluation of biogas projects. However, there is lack of any certificate courses in

the bio energy sector (Academician). As far as procurement of organic waste as

feedstock for the plants are concerned, procurement of fully segregated waste is the

biggest barrier to bio methanation projects (Entrepreneur).

F 7. Legiti mization An emerging technology often meets resistance as most often;

society will be initially opposed to change. There should be support for thetechnology from the general public, civil society and others. Advocacy groups that

can positively influence policy making and garner public support for the technology

also form an important role.

There are no formal industrial associations in the WTE sector and also the failure

rate of many biomethanation plants in the MSW sector is frequent. Hence the need

for more coordination among the various players is required so that they may gainfrom the exchange of ideas and experience. There are many NGOs operating in

SWM and their efforts and grassroots level knowledge need to be tapped so as to

involve more stakeholders in biomethanation projects (Entrepreneurs).


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Discussion For the TIS system studied, i.e. the biomethanation of medium and large scale

anaerobic digesters for solid waste in urban areas, it is evident that none of the corefunctions related to the TIS system are in proper execution.

At the take-off phase of any TIS, there are various interdependencies between the

system function as specified by the literature.

Figure 1: Functional interdependencies at development phase of TIS

Entrepreneurial activities can function properly if backed by proper Guidance of the

search and Resource mobilization. Limited entrepreneurial activity in this field can

be explained by low performance of the Guidance of the Search function as there is

no overarching vision or policy regarding medium and large scale biogas plants in

India. The Resource Mobilization function in terms of technology, manpower,

financial support performs marginally better but has a large scope for improvement

on a scale to accelerate entrepreneurial activity.

Sufficient entrepreneurial activity influences the legitimization of technology and

vice-versa. As entrepreneurial activity in the field is limited there is lack of

awareness regarding benefits of this technology and hence there is low demand for it.


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Positive advocacy for this technology can be built up by collaboration with other

players working in the field of decentralized waste management.

Proper acceptance and legitimization of the technology in turn influences market

formation and resource mobilization. Unless decentralized waste managementthrough anaerobic digestion can be established as a creditable technology not just as

an environment friendly option but as a stable and cost effective source of energy

through biogas, sufficient demand will not be created for this in urban areas.

Legitimization explains the higher demand for other renewable sources of

technology such as Solar PV (Government official).

Market formation also influences the guidance of the search. On the supply side the

numbers of ESCOs in the biomethanation sector are few and limited and are not

represented by any formal association. On the demand side too there is not adequate

demand for the technology from Urban Institutions as well as municipalities. Hence

the low rate of market formation explains low representation of the technology in

government policy and lack of clear vision on its growth projections.


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CHAPTER 6

An alternative and promising form of renewable energy can be seen in biogas.

Biogas occurs naturally and is formed by a microbiological decomposition

process of organic matter. In controlled conditions such the generation process of

biogas can be efficiently established and replicated in order to recover energy

from biological conversion of organic matter. In addressing various energy

demands biogas plants offer several advantages as compared to other forms of

renewable energy production. Depending on the methane concentration biogas is

an energy carrier with multiple options for energy use. The simplest application

is direct combustion for example for cooking or lighting, whereas advanced

technologies can promote biogas for the production of combined heat andelectricity generation. Of more relevance in advanced technologies is the up-

gradation of biogas to an energy rich and high quality fuel. By the removal of

carbon dioxide and other trace gases the up-graded biogas becomes a marketable

commodity product which offers a green alternative to fossil fuels. The up-

graded biogas is in the position to be injected into the natural gas grid or to be

used as an auto-motor fuel. Currently, 45.45 lakh biogas plants are installed in

India. The majority of these biogas plants is small scale and serves predominantly captive energy requirements in rural households. The potential of

medium and large scale biogas plants particular in urban and industrial areas is

by far underdeveloped.

The relevance of biogas lies in addressing several challenges in pollution control,

waste disposal and energy generation. With reference to pollution control biogas

is generated from renewable sources has a carbon neutral footprint. In addition,

biogas is a comparable clean energy carrier and emits considerable lower levels

of potentially harmful emissions. Particular the emission of nitrogen mono- and

dioxide (NOx), carbon mono- and dioxide (COx), and sulphur dioxide (SO2) are

lower than any other cured oil derivative. Today, the environmental aspect

becomes increasingly important facing severe macro environmental problems

and climate change.


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A number of organic substrates can be considered as a potential feed stock

for the anaerobic digestion process, containing primarily carbohydrates,

proteins, fats, cellulose and hemicellulose as main components. These

substrates are for example poultry and cow manures, crop residues, foodleftovers, maize silage, grass, etc. The relevant parameters in the selection of

the feed stock are the availability, collection method, biological and technical

acceptability, gas yield, and nutritional value. Modern biogas plants taking

the type of feed stock into consideration and are erected to achieve an

efficient technical and biological process condition for the digestion process.

Taking the feed stock into consideration three types of biogas plants can be

distinguished, namely municipal, industrial and agricultural biogas plants.

Biogas plants on municipal organic waste are of particular relevance in times

of fast urbanization. The increasing pace of urbanization and rise in per capita

incomes mean an inevitable rise in quantity of wastes generated in cities. On

average the organic fraction of municipal solid waste accounts for 30 to 40%,

which is considerable part of the waste disposal problem. In addition, organic

waste causing severe environmental problems through methane emission in

landfill applications and is a prime source of disease and contamination of air

and water. With an increasing part of the population living in urbanagglomeration biogas plants are an alternative to deal with the organic

fraction of the municipal waste. In this view the biogas plants are to be seen

as a zero-discharge solution for severe problems in waste management as

biogas plants have a comparable advantage to landfill, composting or other

ways of treatment.

A considerabl

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Scale-up of Deployment of Anaerobic Digester

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