1. IMPLEMENTATION OF LOW COST TECHNOLOGY FOR BIOGAS
GENERATION FROM KITCHEN WASTES: AN ALTERNATIVE
SOURCE OF RENEWABLE ENERGY
INVESTIGATORS
Dr. Solomon Libsu (Department Chemistry, College of Science, Bahir Dar
University)
Prof. R B Chavan (IoTex, Bahir Dar University)
Dr. Ayalew Wonde (Department of Biology, College of Science, Bahir Dar
University)
BAHIR DAR UNIVERSITY, BAHIR DAR, ETHIOPIA.

2. IMPLEMENTATION OF LOW COST TECHNOLOGY FOR BIOGAS
GENERATION FROM KITCHEN WASTES: AN ALTERNATIVE
SOURCE OF RENEWABLE
Contents
Project summary
Abstract
1. Introduction
1.1 Environmental issues
1.2 Health issues
1.3 Alternatives
1.4 What is biogas?
1.5 Benefits of biogas
1.6 Substrates used for anaerobic digestion
1.7 Biogas content of different substrates
1.8 Biogas digester technologies
1.9 Biogas program in few developing countries
1.10 Biogas for better life: An African initiative
2. Problem statement
3 Objectives
4. Method and Design
5. Project time schedule
6. Project budget
7. References

3. PROJECT SUMMARY
Project title Implementation of low cost technology for biogas generation from kitchen
wastes : an alternative source of renewable energy
Nature of project Research project of national importance
Investigators Dr. Solomon Libsu (Department Chemistry, College of Science, Bahir Dar
University)
Prof. R B Chavan (Institute of Technology for Textile, Garment and
Fashion Design, Iotex, Bahir Dar University)
Dr. Ayalew Wonde (Department of Biology, College of Science, Bahir
Dar University
Project duration 18 months
Research staff One
requirement
Financial ETB 65,000
requirement
Contact details Prof. R. B. Chavan
Dr. Solomon Libsu
Dept. of Chemistry, Bahir Dar University, Bahir Dar
Phone Office : Mobile: 0918231147
E mail:
Dr. Ayalew Wonde

4. ABSTRACT
About 85-90% of the Ethiopian population lives in the rural parts of the country. This segment of
the population is totally dependent on the use of biomass consisting of firewood, charcoal, twigs,
straw, crop residues, and cow dung to meet its energy demands for cooking and other domestic
needs. It is estimated that the domestic biomass consumption for fuel is as high as 94% with
very little use of modern sources of energy such as electricity and liquefied petroleum gas (LPG).
The use of biomass as fuel has serious ill effects such as degradation of environment due to
deforestation, loss of soil fertility due to diversion of animal manure which acts as fertilizer and
various health hazards particularly associated with rural women and children. It is estimated that
in the past 50 years the land covered by forest has dropped from approximately 50% to less than
3%. Some experts attribute this mostly to forest clearing for cultivation and cutting trees for fuel,
activities highly exasperated by population growth which is estimated to occur at an average
annual rate of 2.6%. The current rate of deforestation is estimated to cover 200,000 hectares of
land per year. Unless the rate of deforestation is arrested, Ethiopia could lose all its natural
forests in 20 years. The use of cow dung and other animal manure as a source of fuel might be
considered responsible, at least in part, for reduction in soil fertility and reduced crop yield.
Biomass combustion in households using traditional three stone fire place that lacks any
provision for smoke exhaust exposes particularly women and children to smoke containing
harmful products. Prolonged exposure to smoke is responsible for coughing, wheezing, acute
respiratory infection, chronic obstructive lung disease, adverse pregnancy outcomes and lung
cancer. Deforestation has made fire wood scarce as a result of which women and their young
ones are forced to spend more time in fetching fire wood. In addition to being a heavy burden,
fire wood fetching, in conjunction with other factors, is taking so much of the time of children
that it may be said to be adversely affecting the literacy rate due to non-availability of time for
education.
In light of the reasons stated above, it is felt imperative that Ethiopia develop an alternative
energy source that ensures sustenance and availability of its fuel wood or derivatives thereof.
Generation of biogas by anaerobic digestion of animal manure particularly cow dung, human
excreta and kitchen waste is considered to be one such alternative. The technology of biogas has
been successfully used in India and China since last 50 years and until now 3.8 million and 5
million domestic biogas plants have been installed in India and China, respectively.

5. In May 2007 a massive program “Biogas for better life: An African initiative, integrated
biogas and sanitation programs in Sub-Saharan Africa” was launched in Nairobi. The
purpose of this initiative is to provide 2 million biogas digesters to the households in Sub-
Saharan Africa over a period of 15 years. According to this program 10,000-14000 biogas plants
will be installed in Ethiopia by 2013.
This ambitious program envisions the use of cow dung and human excreta as the main source for
biogas generation using fix dome bio digester. Although the digester can be used for a long
period of time, it has several drawbacks. Most importantly, it is highly costly in light of the rural
Ethiopian economy. The cost of each digester is estimated to be Birr 7500 out of which a
household will have to contribute Birr 4300 and the balance will be given in the form of subsidy.
There is also micro credit loan provision for the households. In spite of subsidy and loan
provision it is felt that installation of biogas digester under the Africa Initiative Program will put
financial burden on the households. In the present project, it is proposed to introduce a low cost
digester of plastic tank like the one used for water storage along with kitchen waste as source for
biogas generation. Thus the present project will deviate from the Africa Initiative Program on
biogas on two counts. Firstly, it is intended to use kitchen wastes as source for biogas generation
in place of cow dung and human excreta. Secondly, low cost plastic tank digester shall be used in
place of expensive underground fix dome digester. It is envisaged that the cost of plastic tank
digester will be half of that of the fix dome bio digester proposed by Africa Initiative Program.
The successful outcome of the project will provide a low cost biogas technology with alternate
source. The project will also support the government’s initiative in popularizing the biogas
technology which has already been successfully utilized in India and China and will also help the
University to fulfill one of its goals of social transformation for better living through research
and development.

6. 1. Introduction
In order to understand the need for the development of low cost technology for the generation of
biogas as a renewable source of energy to address environmental and health issues on long term
basis, it is necessary to understand the present practice of household energy consumption and its
devastating impact on environment and health of rural and urban poor population.
In Ethiopia 85-90% of the population is dependent on traditional biomass (e.g. firewood,
charcoal, twigs, straw, crop residues, and cow dung), to meet their household energy needs. The
other available sources of energy are kerosene, electricity and LPG. The consumption pattern of
these energy sources by households is given in Table 1.
Table 1. Energy consumption pattern by households in Ethiopia*
Variable Fuel type Households
Distribution of Elec., LPG 1.4%
household Kerosene
by fuel type Charcoal 1.3%
Firewood 81.3%
Other (cow dung, 16%
Crop waste, twigs
Etc)
% households using Elec., LPG 1.40%
purchased fuel Kerosene
Charcoal 1.30%
Firewood 20.35%
Total 23.05%
% households collecting 77.1%
Firewood
*Source: Biogas for better life: An African initiative 2007
Table 1 indicates the % households consuming different types of energy sources. Table 2
indicates the energy consumption pattern in rural Ethiopia

7. Table 2 Energy consumption pattern in rural Ethiopia
Energy source % consumption
Kerosene 3.0
Electricity 1.0
Crop residue 12.0
Cow dung 7.0
Firewood and 77.0
Charcoal
Source Kieflu et.al Research Journal of Forestry 2009
Thus 77% of total energy consumption consisted of firewood and charcoal while another 19%
consisted of agricultural residues; only roughly 4% was met by modern energy sources such as
kerosene and electricity.
There is also a difference in the energy consumption pattern between rural and urban population
as indicated in Table 3
Table 3 Energy consumption pattern between rural and urban population
Energy type Consumption %
Rural Urban
(Addis
Ababa)
Firewood 85 32
Crop residue 12.7 8.0
Charcoal 2.0 5.0
Kerosene 0.21 42
Electricity 0.05 6.5
LPG 0.07 6.5
Source Ethiopian central statistical Authority 2004
Table 1-3 indicate that there is high dependency of large population on fire wood and
agricultural waste which is responsible for serious environmental and health issues.
1.1 Environmental issues
Deforestation
The most significant implication of high dependency on biomass for fuel is its association to
deforestation. The wide spread practice of wood cutting for fuel is the primary cause of

8. deforestation in Ethiopia. Historically, Ethiopia was one of the “forest” rich nations in the
world. In just the past 50 years the land covered by forest has dropped from approximately 50%
to less than 3%. Some experts attribute this mostly to forest clearing for cultivation and cutting
woods for fuel and other purposes. All these practices have been on the rise, presumably due to
poor management and a rapid rate of population growth. The current rate of deforestation is
estimated to be 200,000 hectares of land per year. In fact a recent National Geographic Magazine
stated that at the current rate of deforestation, Ethiopia could lose substantial proportion of its
natural forest in 20 years. As a result of this relentless deforestation, large areas are now exposed
to heavy soil erosion. In fact at this current rate of deforestation, it is estimated that fertile topsoil
is lost at a rate of 1 billion cubic meters per year resulting in a massive environmental
degradation and serious threat to sustainable forestry. Due to this forest degradation, increasing
numbers of Ethiopians have become vulnerable to the effects of drought. The severity of the
devastating droughts and the resulting famines in 1972/1973 and 1984/1985 can be attributed
directly to an accelerated deforestation due to wood cutting for fuel and land clearing for
cultivation. The wide spread practice of using wood, cow dung and crop residues for fuel,
coupled with a rapidly growing population, will undoubtedly increase and hasten the
susceptibility of open land to erosion unless alternate renewable source of energy is introduced
as a substitute to biomass burning.
1.2 Health issues
In-door air pollution
As discussed earlier, biomass fuels such as wood and its derivatives are used widely in
developing countries like Ethiopia, especially in rural and poor urban areas. In addition, due to
the use of traditional three stone fire in open air the burning efficiency is only 5-10% compared
70 - 80% when energy efficient stove is used. The biomass is composed of complex organic
matters including carbohydrates that contain carbon, nitrogen, oxygen and other elements in
trace amounts. Smoke emission during burning of these domestic fuels is the major source of
indoor air pollution, especially in rural and poor urban communities. This smoke contains
pollutants and particulates that adversely affect the health of women. In rural areas, infants are
generally cradled in the back of their mothers who are doing the daily gathering of fuel and
cooking which exposes them to these harmful products. These pollutants are the major causes

9. of chronic bronchitis and lung diseases. A further concern related to indoor air pollution is the
level of carbon monoxide production during cooking and baking. Carbon monoxide exposure
results in higher fatal carbon monoxide–hemoglobin (COHb) interaction. This has a more severe
effect on pregnant women resulting in either fetal damage or low birth weight of infant.
World Health Organization (2004) estimates that, indoor air pollution due to smoke results in 1.6
million deaths worldwide each year, 24% of which occur in Africa; the primary cause of this
indoor air pollution is traditional fuels burned in highly inefficient stoves. Ethiopians
undoubtedly take their toll in this count. Such indoor air pollution is responsible for coughing,
wheezing, acute respiratory infection in children, chronic obstructive lung disease, adverse
pregnancy outcomes and lung cancer.
World Health Organization (2006) estimates that 50% of worldwide deaths of children under the
age of five are caused by indoor air pollution due to smoke. In Ethiopia, the proportion of deaths
due to indoor air pollution among the children under the age of five is a staggering 80%.
Burden on women
As the degree of deforestation increases, so does the amount of time spent on searching for
firewood. This burden for survival is carried almost entirely by women. In villages, women have
to spend more times in fuel collection. In a poor country like Ethiopia, studies have shown that
women spend between 11-14 hours for daily chores. This heavy workload in the long run will
affect their health. This is because the energy expensed is more than the intake of food to
accomplish daily task.
Time spent by women
According to World Bank (2006) report, not only do rural Ethiopian women travel up to 12
kilometers from their home to gather fuels, but they are also forced to collect inferior fuels in the
form of bushes, twigs, roots, and crop residues, all of which translate into longer preparation and
cooking times. The same is true for urban poor women who also operate under extremely harsh
conditions and, like their rural counterparts, have to walk long distances on harsh terrain, often
barefoot, and with heavy loads. Traditional healers often treat women for severe abdominal
pains attributed to carrying these heavy loads over long distances.

10. Effect on literacy
The more time spent on collection and preparation of biomass for domestic fuel, the less time is
available for pursuing more productive activities such as education. This is unfortunate in a
country where, in 2003, only 41.5% of the adult population was literate and only 57.4% of the
youth population was literate (UNDP, 2005). With heavy workloads and low-income livelihoods,
women also cannot manage without their children, particularly their daughters. The effect of this
is that 46% of those eligible are enrolled in primary schools, and just 15% of those eligible are
enrolled in secondary schools.
1.3 Alternatives
Fuel efficient stove is not a permanent solution
The environment and health issues enumerated above are points of concern to Ethiopia as well as
most of the developing countries. Several national and international programs have been
initiated in developing countries including Ethiopia to address environment and health related
issues emanating from burning of biomass as a source of household energy. One such program
is the development of fuel efficient stove. However, the fuel-efficient designs of stoves for
cooking do not address the environment and health issues on permanent basis but only prolong
the devastating environment and health problems. Therefore, the technology of fuel efficient
stove, though useful, is not a permanent solution to the environment and health issues.
Biogas as an alternate source of energy
As stated above, unless an appropriate intervention geared towards the development of
alternative renewable energy source is instituted in the near future, Ethiopia will find itself in a
dangerous situation in terms of sustaining the availability of fuel wood or its derivative. Thus
deforestation and health hazards cannot be reduced without providing alternatives to the current
way of cooking. In the absence of alternate renewable source of energy, people will continue
relentless deforestation that will endanger the eco-system and their lives beyond repair.
Generation of biogas from cow manure, human excreta and kitchen waste is considered to be
one such alternative. The present project will focus on exploring the feasibility of the use of
kitchen waste as an alternative source of biogas to address the household energy demand in an
environmentally and user friendly way.

11. 1.4 What is Biogas?
Biogas is the gas produced by anaerobic digestion of waste materials of plant and animal origin.
Biogas is a mixture of methane (60-70%), carbon dioxide (30-40%) and traces of other gases like
hydrogen sulphide and hydrogen. Methane in biogas provides a source of fuel without smoke.
Anaerobic digestion (AD) is the process by which plant and animal material is converted into
useful product by micro-organisms in the absence of air. Biomass is put inside a sealed tank and
naturally occurring micro-organisms digest it, releasing methane that can be used to provide heat
and power. The material left over at the end of the process, known as bio-slurry, is very rich in
nutrients so it can be used as fertilizer.
This means that generation of biogas is carried out by using waste materials of plant or animal
origin which can be potential source of environmental pollution if disposed off without
conversion. Most importantly, it provides an alternate source of renewable energy and thus
reduces the burden on the use of biomass as well as fossil fuel as a source of energy. The bio-
slurry provides organic fertilizer which, unlike synthetic fertilizers, imparts no detrimental effect
on soil as well as environment.
1.5 Benefits of biogas
Developing country context including Ethiopia
The benefits of biogas are now well recognized. It has resulted in a smoke-free and ash-free
kitchen, so women and children are no longer prone to respiratory infections, and can look
forward to longer, healthier lives. Women are spared the burden of gathering firewood. Cow
dung, which is burnt as fuel, can be saved as fertilizer. Both these factors will contribute to
protecting the forests and allowing the forests to regenerate. The sludge remaining after digestion
is rich in valuable nutrients and can be used as top quality fertilizer that guarantees better crops.
In rural areas where there is no electricity supply, the use biogas as a source of light has enabled
women to engage in evening study, has made easier literacy classes and other home and
community activities.
Cattle dung is no longer stored in the home, but is fed directly to the biogas digester along with
toilet waste. The anaerobic digestion process also destroys pathogens. As a result, sanitation has
greatly improved.

12. Global context
Disposal of domestic and industrial waste is normally carried out in the form of landfills. With
increasing population size and industrialization, the spaces available for landfills are decreasing.
Beside, the waste materials so disposed also become a source of environmental and health
hazards due to harmful gases that are released upon decomposition of organic materials in the
waste. Such gases are popularly known as green house gases which are responsible for the
phenomenon known as global warming. Thus, the conversion of organic solid waste (plant and
animal origin) and converting it into biogas, which is used as fuel for domestic use or for
generation of electrical energy, provides an eco-friendly solution to the recycling of solid waste.
The United Nations Framework Convention on Climate Change has set up a Clean Development
Fund, and the World Bank has put together a Carbon Finance Unit to allow rich countries, which
are pumping more carbon into the atmosphere than is allowed under the Kyoto Protocol, to buy
emissions that poor countries prevent through conserving forests or promoting renewable energy.
This is known as carbon credit. An article in the Nepali Times pointed out that Nepal's
successful biogas program not only brought farmers a non-polluting fuel, conserved forests and
provided high quality fertilizer for crops. Moreover, Nepal also benefits in terms of hard cash
received from the industrialized nations for not burning firewood to release carbon dioxide into
the atmosphere.
1.6 Substrates used for anaerobic digestion
Any organic matter of vegetable or animal origin can be used for conversion into biogas through
a process of anaerobic digestion. Typically substrates used for biogas generation are as follows
• Sewage sludge (human excreta)
• Food waste
• Waste from food industry
• Manure from cows, pigs etc.
• Residues from agriculture
1.7 Methane content of different substrates
Following table shows the biogas yield from different substrates that can be used for biogas
generation.

13. Table 4 Methane content of few waste substrates*
S.No Substrate Biogas yield
M3 kg-1
1 Pig manure 0.25-0.50
2 Cow manure 0.2-0.3
3 Chicken food waste 0.35-0.60
4 Human excreta 0.03 m3/person
4 Fruit and vegetable waste 0.25-0.50
5 Food waste 0.5-0.6
6 Garden waste 0.2-0.5
7 Leaves 0.1-0.3
*Source: Basics of Energy Production through Anaerobic Digestion of Livestock Manure
Purdue Univ. publication 2008
1.8 Biogas digester technologies
Biogas digesters can be divided into two categories
A. Industrial bio digesters
B. Domestic bio digesters
Industrial bio digesters are mainly used in developed countries for the anaerobic digestion of
municipal solid waste to release the pressure on landfill sites. The biogas thus generated is
mainly used for electricity production.
Domestic bio digesters are most popular among the developing countries because of the
possibility of generation of biogas on small scale at household level. The gas generated is used as
a fuel to minimize the use of biomass as fuel.
Following types of domestic biogas digesters are popular for small scale production of biogas
1. Fixed dome digester
2. Floating dome digester
3. Plastic bag digester
4. Inclined digester

14. The technical details of the digester technologies are beyond the scope of the present project
proposal. Only the salient features are mentioned
Among these, the fixed dome digester, though expensive, are most widely used because of their
long life. There are, however, some disadvantages associated with the use of fixed dome digester
and these are indicated in the problem statement section. Fixed dome digesters are constructed
underground. Digesters of 4, 6, 8, 10 M3 size are popular for small family having 2-6 cattle.
Being expensive, these digesters are mainly installed at the institution level. Installation by
individual household has been possible only through subsidies.
The floating plastic dome, plastic bag and inclined digesters are economical. Among these the
plastic bag digester is most economical but very delicate and need considerable precautions
during its handling and thus have only short life. The other two types i.e. floating dome/ inclined
digesters will be explored for the production of biogas during the present project.
1.9 Biogas program in few developing countries
Globally, biogas technology seems to have outnumbered the dissemination of other decentralized
energy technologies, with a reported 16-25 million units installed worldwide.
Biogas digester technology is well established as an appropriate sustainable energy source in
many parts of the developing world. The technology has been implemented on large scale in
China, India and Nepal.
Majority of developing countries including Ethiopia have national programs on biogas
generation. All these programs are supported by national and international funding. Subsidy
varying between 30-75% is given to households in order to popularize the program. Following
table will give an idea of domestic biogas installations in few developing countries. Though the
data includes only limited countries, it is enough to understand the importance of the biogas
program and its relevance to Ethiopia.

15. Table 5 Biogas installations in few countries
Country No. of domestic
biogas digester
Installations
World wide 16-25 million
China 5 million
India 3.8 million
Nepal 155,000
Vietnam 25000
Combodia 17500
Ethiopia 1000
Tanzania 1000
Kenya 150
Source: Assorted
1.10 Biogas for better life: an African initiative, integrated biogas and sanitation programs
in Sub-Saharan Africa
In May 2007 the “Biogas for Better Life: an African Initiative” was launched in Nairobi. The
purpose of this initiative is to provide 2 million domestic biogas plants to households in Sub-
Saharan Africa
The initiative aims to achieve the following by 2020:
• 2 million biogas plants installed (90% operation rate)
• 10 million Africans benefiting in daily life from the plants
• 800 private biogas companies and 200 biogas appliances manufacturing workshops
involved or established
• 100,000 new jobs created
• comprehensive quality standards and quality control systems developed and in use
• 1 million toilets constructed and attached to the biogas plants
• 80% of the bio-slurry utilized as organic fertilizer
• agriculture production raised by up to 25%
• health and living conditions of rural household improved and death of rural household
reduced by 5000 each year
• drudgery reduced by saving 2 to 3 hours per day per household for fetching wood,

16. • cooking and cleaning the pots
• health costs saved by up to US$ 80 to 125 per family per year
• 3 to 4 million tonnes of wood saved per year
• Greenhouse gas emissions annually reduced by 10 M tonnes of CO2 equivalent.
The African countries and the Organizations involved are given in the following table
Table 6 Organizations involved in Biogas-Africa initiative program
Organization African Countries
German Technical Cooperation (GTZ) Burkina Faso, Rwanda, Tanzania
& Biogas Africa Initiative
Netherlands Development Organization (SNV) Burkina Faso, Cameroon, Ethiopia,
& Biogas Africa Initiative Rwanda
ETC Foundation & Biogas Africa Initiative Sudan, Kenya, Uganda
West African Economic and Monetary Benin, Guinea Bissau, Niger, Togo, Senegal
Union (UEMOA)& Biogas Africa Initiative
All the above organizations All countries in Sub-Saharan Africa (SSA)
Source Biogas for better life: An African initiative 2007
The country wise plan for domestic biogas plant installations is as follow:
Table 7 Country wise plan for domestic biogas plants
Country No. of biogas plants
to be installed
Ethiopia 10000-14000
Uganda 20,000
Rwanda 15000
Tanzania 12000
SSA 2 million
countries
Source Biogas for better life: An African initiative 2007
The program for Ethiopia, Uganda, Rwanda and Tanzania will continue for five years (2013)
and for other SSA countries it will continue for 15 years
Finance

17. The total financial requirements are summarized in Table 8
Table 8 Financial requirements for biogas installations
Country Targeted Total subsidy Total cost
No. of plants US $ US $
Uganda 20,000 4,000,000 44,627,282
Rwanda 15,000 4,500,000 34,959,357
Ethiopia 10,000 1,860,000 23,774,625
SSA 2 million 400,560,000 4,306,057,409
countries
Source Biogas for better life: An African initiative 2007
The importance given to the biogas program for better life will be clear from the above tables.
2. Problem statement
Like other developing countries, the rural population and poor urban population in Ethiopia; is
entirely dependent on the use of biomass consisting of firewood, charcoal, twigs, straw, crop
residues, and animal dung as a source of fuel. This is responsible for serious environmental
degradation due to deforestation, poor health of households particularly women and children and
heavy work burden. The heavy work burden on women and children is indirectly responsible
for poor literacy. Therefore, there is urgent need to provide economical and sustainable alternate
source of energy to minimize deforestation, improve living standards and literacy of rural
masses. Biogas, which consists of methane as a major component, is considered to be one such
alternative renewable source of fuel. The biogas can be produced on small scale by households
using cow manure, human excreta and kitchen waste using suitable digesters. The government
initiative launched in 2007 envisages setting up 10,000 to 14000 domestic biogas plants in
Ethiopia by 2013. The technology adopted is based on fix dome digester. It is estimated that the
cost of each biogas plant of 6 m3will be ETB 7500, out of which each householder will have to
contribute ETB 4300 and balance money will be provided as subsidy. The Government has also
plans to provide loan facility to the householders for his/her contribution. It is strongly felt that
with the present economic conditions among the rural population the contribution towards the
cost of biogas plant will be heavy burden on the householders.

18. 3. Drawbacks of fixed dome digester
Though the fixed dome digester has long life, it is associated with the following drawbacks.
1. The digester is expensive for rural economy in the absence of subsidy and loan facility,
the provision of which has been made in the national biogas program.
2. The dome is constructed underground where the temperature is lower compared to
surface temperature, whereas the performance of anaerobic digestion is better at higher
temperature.
3. For construction of 6 m3 digester, the free space required is 18x18x18 ft, which may not
be available with many households.
4. The brick construction often develops cracks from which gas can leak. The digester being
underground it will be difficult to locate such cracks. Hence the required quantity of gas
may not be available.
5. The digester needs supervision, which may not be provided by every household.
4. Substrate for biogas generation
In the Government initiated national program of biogas, the substrate used will be cow dung and
human excreta. The philosophy behind this choice is to provide hygienic living environment in
addition to biogas generation. Though the choice of the substrate is ideal, there are psychological
barriers associated with the use of human excreta. Also the size of biogas digester suggested in
the national biogas program is 6 m3 which will need feeding of minimum 20 kg of cow dung per
day. For this every household will need a cattle stock of 4-6 cows. This may not be possible with
every household.
For the reasons stated above, it is suggested in the present project proposal to use food and
vegetable waste which is always available in the household as a substrate for biogas generation.
In the present project proposal it is proposed to overcome the difficulties associated with the
fixed dome digester. It is proposed to use low cost plastic tank digester like the one used for
water storage. The digester will be fixed on the ground. The digester will be easy to supervise
and maintain. It is envisaged that the cost of the proposed biogas plant will be almost half of the
cost estimated in the Government initiated national biogas program.

19. Secondly the choice of the substrate will be kitchen waste in place of cow dung and human
excreta suggested in the national biogas program.
Thus on both accounts i.e the choice of low cost digester technology and the choice of substrate
for biogas generation the present project is different but supplementary to the national biogas
program. It is therefore strongly felt that the outcome of the present project will support the
government initiative in popularizing the biogas technology for better living and to minimize the
danger of deforestation.
3. Objectives
General Objective
The principal aim of the project is to implement low cost biogas generation technology in
addressing environmental and health issues
Specific objectives
1. To use plastic tank digester like the one used for water storage. The tanks will be placed
on the ground rather than underground.
2. To use kitchen waste (left over food and uncooked vegetable waste) as a source for
biogas generation instead of cow dung and human excreta.
3. To study the biogas yield and its sufficiency for meeting the fuel requirements of a
family.
4. Testing the technology in three households to get the feedback for any improvements if
required.
5. To workout the cost and economics of the technology
6. Showcasing the technology in the form of workshop to government and private agencies
and households for further dissemination.
4. Method and Design
The following methodology will be adopted for the implementation of the low cost digester
technology of biogas generation using kitchen waste.
1. Appointment of researcher or 2 Graduate students to work on the project under the
supervision of project investigators
2. Market survey and purchase of suitable plastic tanks and other accessories needed for the
construction of digester.

20. 3. Digester construction
4. Collection of kitchen food waste from student cafeteria in the form of cooked food waste
and uncooked vegetable and other wastes of organic origin.
5. Standardization of parameters for anaerobic digestion of collected waste and estimation
of biogas yield. Most important parameters will be pH, temperature and initial time
required for biogas generation and subsequent feeding of waste for continuous
availability of gas for daily use.
6. Analysis of difficulties faced and their solution.
7. Installation of biogas digester in three households to get the feedback of their experiences
and further improvement if any.
8. Report writing.
9. Conducting workshop inviting the government and private agencies and households for
further dissemination of technology.
5. Project time schedule
S.N Activity Time required
o Months
1 Visit to existing biogas generating sites in/near Bahir Dar Two weeks
2 Appointment of Researcher 1 month
3 Market survey for purchase of items required and assembly of 1 month
digester
4 Collection of food waste and initiation of anaerobic digestion (Initially 2 months
minimum 1.5-2 months are required for generation of biogas).
5 Standardization of process parameters for getting optimum biogas 6 months
yield on continuous basis
6 Field testing of technology by setting 3 biogas digesters in three 6 months
households for feedback and further improvement if needed
7 Report writing 1 month
8 Workshop preparation for inviting stakeholders for further 1 month
dissemination of technology
Total period 18.5 months

21. 6. Project budget
S.No Component Amount
ETB
1 Salary of researcher (2 Graduate students) 27,000
@1500 ETB per month for
18 months
2 4 Plastic tanks and accessories 20,000
For installation of bio digester
(1 for research and 3 for
Field testing of technology)
Estimated ETB 5000 per digester
Including labor charges for
assembly of digester
3 Workshop for technology 10,000
Dissemination (Travel cost, tea, lunch/snacks to invited
stake holders, households,
4 Report writing (Stationary, computer 2.000
Peripherals, secretarial assistance)
5 Travel during the project period 5,000
6 Contingency 6,400
Total 70,400

22. References
1. Urban Fuel Demand in Ethiopia, Zenebe Gebreegziabher, Arie J. Oskam and Demeke Bayou,
Environment for Development, (August 2010)
2. Wood fuel demand and sustainability of supply in south western Ethiopia (2009), Kiflu haile,
Mats Sandewall, Kaba Urgessa, Research Journal of Forestry, 3(2), 29, 2009
3. Human waste based biogas plant design for Universities in Ethiopia; a case study in Bahir-Dar
University, faculty of engineering, Moges Ashagrie MSc thesis 2009
4. Biogas Generation from Human Excreta A multi-dimensional Sanitation Approach- Experience
of Lem Ethiopia, Mogues Worku, Presented at the 3rd International Dry Toilet Conference,
Tampere, Finland August 12-15/ 2009
5. Biogas in Ethiopia: From Skepticism to Enthusiasm, Willem Boers & Getachew Eshete, SNV
Ethiopia Document 2009
6. National Biogas Program-Ethiopia, Program Implementation Document
January 2008
7. Biogas for better life: An African initiative, A cost-benefit analysis of national and regional
integrated biogas and sanitation programs in Sub-Saharan Africa , April 2007
8. Commercialisation and business development in the framework of the Asia Biogas Program,
Wim J. van Nes, Seminar on “Policy options for expansion of community-driven energy service
provision” Beijing, China, 11-12 March 2007
9. Household determinants of fuel wood choice in urban Ethiopia: a case study of Jimma town,
Abebaw, Degnet, Journal of Developing Areas, 2007
10. Biogas Bonanza for Third World Development http://www.i-
sis.org.uk/BiogasBonanza.php, 2005
11. Use of biomass-Ethiopia, GTZ, Germany, 2004
12. The economics of a biogas
digestorhttp://www.ilri.org/InfoServ/Webpub/fulldocs/Bulletin30/economi.htm
13. Kitchen Waste Based Biogas Plant, http://www.dae.gov.in/ni/ninov02/biogas.htm
14. Wood fires that fit, http://journeytoforever.org/at_woodfire.html
15. Occupational, Health Hazards of Improper Garbage Disposal,
www.addisfortune.com/agenda.htm
16. Household Energy Use in Ethiopia http:// http://www.hedon.info/Ethiopia
17. The making of Injera/Enjera: http://www.zelaleminjera.com/products.html
18. Cook stove for Ethiopia, http://newscenter.lbl.gov/feature-stories/2010/06/29/berkeley-lab-
makes-cookstoves-for-ethiopia/

23. 9. Curriculum Vitae of investigators
1 Dr. Solomon Libsu
Prof. R B Chavan
Educational background
No Field of study Degree Class Year university
completion
1 Chemistry B.Sc.(Hons) First 1964 Marathwada Univ. India
2 Textile B.Sc.(Tech) First 1966 University of Bombay, India
Chemistry
3 Textile M.Sc. First 1968 University of Bombay, India
Chemistry (Tech)
4 Textile Ph D (Tech) 1974 University of Manchester,
Chemsitry Inst. of Science and
Technology England
Academic achievements
S.No. Academic achievements Number
1. Total teaching experience at 30 years
Indian Inst. of Technology, Delhi,
India
2. Experience as Professor 20 years
3. Head of Department 3 years
4. Industrial experience 04 years
5, No. of Ph.D students guided 11
6. No. of M.Tech students guided More than 50
7. Publications
International 30
National 53
Paper presentations 43
Total 126
8. Sponsored projects
International Agency 01
Govt. Agency 03
Industry 03
Major consultancy INR120 million 01
Books edited 04
Books published 02
Special Journal issue edited 01

24. Chapter contribution in International 01
Book on dyeing
Book accepted for publication (Book 01
on Ethiopian textile Ind. written after
joining Bahir Dar University in 2009
Present employment
Professor, Inst. of technology for Textile, Garment and Fashion design (IoTex), Bahir Dar
Univerisy, Bahir Dar, Ethiopia
Period
October 2009 till date.
Research profile
1. Technical interventions for the development of hand spinning and hand weaving sector
in rural India
Manual spinning and handloom weaving is prevalent in rural India. Fabric thus produced is
known as khadi. Khadi and Village Industries Commission under the Ministry of Micro, Small,
and Medium Enterprises (MSME) is responsible for the development of the Khadi sector. The
sector provides employment opportunities to large number of rural population. The
manufacturing activities being carried out on small scale using traditional technologies, the
sector is deprived of modern technical interventions.
Following technological inputs have been provided and implemented in the field
1. Preparation of Quality assurance manual for yarns and fabrics
2. Product design development
3. Transfer of the technology of fabric and garment finishing
4. Standardization and transfer of the technology of dyeing with natural colors
5. Development of solar energy operated mini-spinning unit for removal of drudgery of
manual spinning operation and improvement in productivity and quality of yarn
produced. The technology has been accepted by the Ministry of MSME and
implemented in the khadi sector on all India basis
2 Environmentally friendly chemical processing
The research activities were supervised at the master and Ph D level in the following areas

25. 1. Replacement of hazardous sodium sulphide with eco friendly glucose during dyeing of
cotton with sulphur dyes.
2. Development of eco-friendly reducing system based on sodium gluconate for dyeing of
cotton with vat dyes.
3. Transfer printing of cotton and polyester cotton blends
4. Development of solubility parameter concepts for better understanding of transfer
printing mechanisms