Energy and Power Engineering, 2013, 5, 506-512
http://dx.doi.org/10.4236/epe.2013.58055 Published Online October 2013 (http://www.scirp.org/journal/epe)
Dissemination and Problems of African Biogas Technology
Cyimana Mulinda, Qichun Hu*, Ke Pan
Biogas Institute of Ministry of Agriculture, Chengdu, China
Received January 16, 2013; revised February 16, 2013; accepted February 23, 2013
Copyright © 2013 Cyimana Mulinda et al. This is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
ABSTRACT
The present status of biogas technology in Africa was briefly reviewed focusing on biogas market potential, stake-
holders, investments and bottlenecks. Africa is endowed with important biomass reserve considered as a potential for
anaerobic digestion. However, the over reliance on wood and fossil fuels remains significantly overwhelming. This is
due to the number of challenges in the f ield which led to underestimate at some exten t the benefits of biogas techno logy.
Unreliable and inefficient use of biomass fuel, which contribu tes to the greenhou se gas emissions still, h as kept its pref-
erence in primary energy balance. Despite the huge potentialities and biomass resources for anaerobic digestion in Af-
rica, the dissemination rate of biogas in Africa is struggling to meet biogas market demand. Nevertheless, there are a
number of problems to address especially narrowing down the gap between biogas market demand and supply. This
paper consists of an introduction and the status of the energy sector in Africa, and then discusses current dissemination
of biogas development, finance and stakeholder contributions, challenges and a conclusion.
Keywords: African Biogas; Dissemination; Potential; Bottlenecks; Bene fits
1. Introduction
Biogas technology belongs to Biomass energy which re-
fers to a wide range of biomass fuels such as wood, char-
coal, agricultural residues and animal waste. Biomass
fuels are often used in its traditional and unprocessed
form. African countries continue to mostly rely on bio-
mass to meet the bulk of their household energy require-
ments. The wood fuel scarcity issue has been intensified
by overpopulation, need for cropland, deforestation and
high wood fuels demand usually in the form of charcoal,
accelerating the problem.
Africa faces the problem of low energy consumption
especially in rural area. Only South Africa consumes
45% of the total electricity generated in Africa while
North Africa consumes 30%, and this effectively leaves
Sub Saharan Africa where 80% of the continent popula-
tion lives with only 24 % of the total electricity generated
in Africa [1].
Biomass energy conversion would assist in mitigating
the negative impact of wood fuels and high fossil fuel
imports, by producing biogas as alternative energy [2]. It
may also create opportunity towards unemployment re-
duction, livestock industry develop ment; and hence, rural
people’s welfare may be improved. Biogas technology
benefits are not only limited to energy for cooking, light-
ing, power generation or biofuel. There are other benefits
like bio-effluent as fertilizer which farmers need and
used to buy. Its positive effect on the soil quality, bene-
fits associated with animal husbandry and green-house
gas emission reductions should not be sidelined.
Biomass energy resources in Africa are not yet fully
exploited, mainly due to the limited biomass energy pol-
icy and low investment level. Biogas technology has
been introduced four decades ago with a phase marked
by pilot projects and training of technicians [3]. However,
low access level, lower utilization capacity and mainte-
nance deficiency are usually the characteristics of biogas
technology in Africa.
1.1. Review on Household Biogas Designs
There is a good startup in developing household digester
where contribution from various scientists, engineers and
academicians found to be an important endorsement. It is
characterized by different design forms; rectangle, sphe-
rical, ground and underground digesters. Similarly, the
construction materials vary from mild steel to plastic
sheet and masonry works.
The biogas plants today are multi-functional depend-
ing upon their purposes such as sanitation, energy recov-
ery, wastes management and environmental protection.
*Corresponding a uthor.

C. MULINDA ET AL. 507
Their concept basically responds to its specific purposes,
size and anaerobic digestion model. The concept design
and different design options have impact on gas produc-
tion rate, investment cost, digester monitoring and envi-
ronmental conditions. The effective application of these
concepts ensures whether the digester will perform well.
The fixed dome design models are playing a major role
in the dissemination of household biogas technology in
Africa despite an increasing number of designs on the
market, from which the popular ones are as fo llows.
1.2. Fixed Dome Chinese Digester
It has been experimented in China as early as the mid
1970’s and standardized in 2002 as Chinese GB/T4750-
2002, the profile Figure 1. This model consists of an
underground brick masonry and cement mortar compart-
ment for the digestion chamber with a concrete dome on
the top for gas storage. Thus, in this design the digestion
chamber and the gas storage dome are combined as one
unit. This design eliminates the use of costlier mild steel
gasholder and presents other benefits over Floating drum
digester.
Based on the fixed dome Chinese model principle,
various countries have put forth modified design to suit
out local conditions. The GGC 2047 design model was
adapted in Nepal with some similarities to Chinese fixed
dome model, the profile Figure 2, and in both designs
the size corresponds to the actual volume. The GGC
2047 model is also SNV main promotion methane tank
type. It is now gaining the popularity due to the fact that
it is said to reduce gas leakage often occu rring at the gas
pipe sealing place.
The Center for Agricultural Mechanization and Rural
Technology (CAMARTEC) biogas design model has
Figure 1. Chinese fixed dome model.
Figure 2. GGC 2047 fixed dome model.
come in the same perspective with GGC 2047 model in
Tanzania. It is widely used in East African region known
as CARMATEC design model, the profile Figure 3 [4].
It consists of an underground brick masonry compart-
ment, fermentation chamber, with a dome on the top for
gas storage. In this design, the fermentation chamber and
gas holder are totally combined as one unit. Besides,
there is no scientific recommend ation about those design
models so that the potential client may know which de-
sign model suitable for each specific case.
1.3. Floating Drum Digester
Indian design model which began in the late 1930 and in
1962 the model gained the popularity in India as well as
the sub-con tinent [5]. In the Khad i and Villag e Industries
Commission (KVIC) design, the digester chamber is
made of brick masonry in cement mortar, the profile Fig-
ure 4. A mild steel drum is placed on top of the digester
chamber to store the gas produced.
Thus, there are two separate structures for gas produc-
tion and gas collection. When biogas gas is produced, the
gas pressure pushes the mild steel drum upwards and as
the gas is being used the drum gradually lowers down.
Thus, by observing the level of drum, one can assess the
available gas volume as long as the mild steel drum
floats above the digestion chamber. With the introduction
of the fixed dome Chinese model biogas digester, the
floating drum biogas plant model has become obsolete
due to comparatively high investment, maintenance cost
Figure 3. CARMATEC fixed dome model.
Figure 4. KVIC biogas plant model.

C. MULINDA ET AL. 508
and some design weaknesses.
2. Current Dissemination Status and Market
Potentiality in Africa
Domestic biogas was introduced in some Africa coun-
tries in around four decades ago. However, remarkable
involvement came later in 2008. A number of NGOs
joined in the promotion of the technology and acceler-
ated awareness and dissemination. The result from bio-
gas initiatives and nation al programs showed that there is
a significant increase in number of installed biogas di-
gesters and possible technical skills, co nsidered as prom-
ising upshot for biogas technology in Africa, have been
put in place. This increase is seen in nine countries sup-
ported by SNV where at least 17,000 digesters have been
so far installed in five years, from 2007 to June 2012,
profile Figure 5 [6].
This was a good uptake, but still the dissemin ation rate
is below its expectation and seems to be not convincing
considering biogas market potential and targets in some
selected countries as shown, in profile Figure 6, and
overall target of the year 2020.
The potential for biogas dissemination in Africa may
be defined by biomass resources available for anaerobic
digestion, its affordability and climate versatility. This
potential is a projection of the data available on number
of livestock, agricultural residues, forest residues and
0
500000
1000000
1500000
2000000
2000000
17000
0.85
70000
11172 16
Diges t ernu mbers
Dissemination status
Africa/
WINIROCK
2008
ABPP/ Si x
countries
Figure 5. Target and achievement comp aris on in Africa.
Figure 6. Target and achievement comparison in selected
countries country. Source: Biogas for better life and Africa
biogas partnership program [7].
municipal wastes [8]. This scenario shows that biogas
market in Africa is still potential but making use of these
potentialities is not materialized.
According to the report of biogas for a better life 2007,
the technical potential carried out has found that, for the
continent as a whole, 24% of agricultural households
would qualify for biogas hence they meet the two basic
requirements, sufficient availability of feeding material
and water to run biodigester. Reminding that, the total
cattle population of Africa amounts to 277 million heads
a FAO-2006 figure, with an estimated 168 million do-
mestic cattle heads [9]. Taking some assumptions into
account the technical potential market for domestic bio-
gas in Africa would be estimated at 18.5 million house-
holds [10].
Furthermore, the biogas would be seen as a quick
mitigation on pressure associated with low level of rural
electrification, available power generation and a low fi-
nancial investment in this field. Moreover, the depletion
of biomass fuels and soil quality, increase of agricultural
residues, municipal waste threats, pressing need of safe
environm ent an d sust aina ble sanit ati on all just ify t he need to
go for biogas technology.
2.1. Biogas Market Potential in Intertropical
Zone
Lying within tropics equally to north and south of equa-
tor, biomass resources in this zone are unevenly redis-
tributed. They are gradually concentrated in zone ex-
tending from The Democratic Republic of Congo, the
long of the coastal zone of South West of Africa up to
Senegal [11]. It covers also Central, East and South East
of Africa. It is the region with high opportunities with all
suitable conditions and requirements for installation of
biogas digesters. Around 70% of African population lives in
the region.
2.2. Biogas Market Potential in North and South
African Zone
The North Africa is dominated with Sahara desert from
East to West of Africa and the Sahel, the zone between
desert and Sub Saharan Africa. This part of Africa faces
the water scarcity problems and is known for its cattle
grazing and migrant population. It is obvious that most
households in this zone may not meet basic requirement
for installation of biogas digesters
Kalahari semi-arid sandy savannah located South-
West of Africa supports more animals and plants than a
true desert. Biogas technology can be adap ted at a certain
level in this region. Nonetheless, some countries like
Morocco, Tunisia and Botswana, despite their major part
in desert, have been committed to install some biogas
units. The potential for biogas, for example, in one re-

C. MULINDA ET AL. 509
gion Souss-Massa of Morocco was defined to have, ac-
cording to biomass available, approximately 20,000 po-
tential biogas plants [12].
2.3. Biogas Dissemination across Africa
To comply with safe environmental and sanitary con-
ditions, large, medium and household biogas digesters
have been installed in several African countries. It in-
cludes countries like Burundi, Botswana, Burkina Faso,
Cote d’Ivoire, Ethiopia, Ghana, Guinea, Lesotho, Na-
mibia, Nigeria, Rwanda, Zimbabwe, Tunisia, Morocco,
Tanzania, South Africa and Uganda. Those biogas di-
gesters utilize a variety of feedstock such as waste from
slaughterhouses, industrial waste, animal dung and hu-
man excreta. Some few examples are: biogas digesters to
treat chicken manure and dairy farm manure in Burundi,
public latrines block in Kenya, prisons and boarding
schools in Rwanda, health clinics and Sisal waste in
Tanzania [13].
However, as far as biogas and anaerobic technology
are concerned, South Africa is unique in Sub-Saharan
Africa with advanced anaerobic digestion because of its
high level of economic development and many universi-
ties with state of the art research capacities. Thus, house-
hold digester is the most attempted model and is often
fed with domestic animal manure in Africa. This is due
to the fact that this technology is closely linked to pov-
erty alleviation and rural development [14].
3. Initiatives and Investment from
International Organizations
Since 2008, several stakeholders have been engaged in
different Initiatives and Partnership programs supporting
development of biogas technology in Africa [15]. It
comprises mainly Netherlands Development Organiza-
tion (SNV), Netherland Directorate General for Interna-
tional Cooperation (DGIS), German Technical Coopera-
tion (GIZ), WINROCK International, International Hu-
manist Institute for Cooperation with Developing Coun-
tries (HIVOS) and Biogas Institute of Ministry of Agri-
culture, China (BIOMA) which provides technical sup-
port for domestic biogas programs. Their main objec-
tive is to develop marketable biogas technology by pro-
viding access to a reliable and sustainable clean energy in
Africa.
The African Biogas Partnership Program (ABPP) is a
famous partnership working with Netherland Directorate
General for International Cooperation (DGIS) and SNV
provides technical advisor. ABPP aims to support the
establishment of commercially viable domestic biogas
sector in six selected countries in Africa (Senegal, Burk-
ina Faso, Ethiopia, Tanzania, Uganda and Kenya). This
program began in 2008, in cooperation with HIVOS,
with an aim to reach 70,000 households by 2013 and
optimize organizational and institutional capacities al-
ready available in its working zone. In addition, Camer-
oon is developing its program since 2009 and Benin
since 2010 [16].
Africa biogas initiative was launched in a conference
held in Nairobi-Kenya in 2005 and attended by 135
delegates from 27 African countries, an initiative for in-
stallation of 2 million biogas units by 2020 supported by
WINROCK [17]. Another technical major support in
African biogas technology is provided by Chinese gov-
ernment throughout Biogas Institute of Ministry of agri-
culture (BIOMA) to the technicians and policy imple-
menters from governmental institutions since 1984.
BIOMA has installed biogas digesters in different coun-
tries in Africa and 55 international training courses and
seminars in biogas or renewable energy technology have
been held in BIOMA, Chengdu-China. At least 1300
international biogas experts and technicians from 123
countries have been trained in BIOMA and around 60%
of participants were coming from Africa. This support
from different stakeholders underlines the importance of
biogas technology in Africa, but there is no appropriate
coordination of these partnerships in order to avoid du-
plication or overlapping activities.
The financial conditions and purchasing power for
some households in Africa seems to impede the wide-
spread of biogas techno log y in most of Afr ican countr ies.
Due to this, some stakeholders raise up the idea of sub-
sidy to support and speed up the dissemination. Some
countries in Africa are said to have adopted subsidy
scheme, Rwanda, Ethiopia, and Tanzania among others,
provide subsidies throughout national biogas programs.
The reluctance in providing subsidy seems to be a draw-
back for successful large scale dissemination of the bio-
gas technology, hence it will slow down awareness cam-
paign and targets could not be seen
4. Problems and Challenges
While it is acknowledged for putting in place a good start
and basic foundation, challenges on sustainability and
dissemination rate still are weighing and summarized as
follows.
4.1. Availability of Manure
It is obvious that, after construction of a digester, the
farmer requires to feed his digester regularly with re-
quired amount of animal manure. Biogas digesters in
Africa are usually fed with cattle dung daily. The quan-
tity of manure and the commitment of farmer to entertain
digester is a key to ensuring long term operation.
African family size is relatively big consequently big
digesters and enough amount of animal manure will be

C. MULINDA ET AL. 510
needed to comply with daily gas need. Big digester
means more feeding materials and animal heads. This is
a big concern for farmers when cattle’s breeding is ham-
pered by more difficulties to collect animal feedstock,
water and then sustain the cattle healthy and productive.
The labor need for acquisition of an imal feeding material,
collecting of water for mixing with animal feedstock,
regular maintenance all have increased the stress to the
farmers meaning that the potential biogas users required
to pay more investment and operational cost. These are
seen as drawbacks to the African biogas and any in-
volvement could take into consideration its long term
consequences. Nonetheless, African farmers also didn’t
pay attention to the use of other agricultural waste mate-
rials other than cattle dung as methane raw materials,
such as pig manure, poultry dung and crop straw.
4.2. High Initial Investment Cost
Depending on the size of the digester, its location and
government subsidy availability if any, a potential client
needs to invest in construction of the digester. The
farmer also has to avail the labor required for daily op-
eration and maintenance of digester supervision, storage
and disposal of slurry. The availability of this labor de-
termines if the digester will be well operational. The ini-
tial investment cost is probably the major bottleneck to
the adoption of biogas technology in Africa where an
important number of African population lives under the
poverty line [18].
Considering the total price of digester in selected Af-
rican countries, the cost of 4 m3 digesters is estimated at
around US$ 1000 in Rwan da, US$ 700 in Cameroun and
Kenya, US$ 650 in Tanzania, US$ 600 in Burkina Faso,
US$ 560 in Senegal and US$ 550 in Ugan da, see Table 1.
We also need to remember that, the daily gas need in-
creases with family size, consequently the price will also
increase. Thus, this 4 m3 biogas plant sometimes do not
match with most of African household family size which
means, bigger size and more investment are required.
In this situation, biogas technology seems to be only
affordable by the happy few at the top of demand pyra-
mid. To develop biogas sector in Africa requires effort
from different stakeholders to establish different working
mechanisms, subsidy scheme policies and reliable credit
facilities to ease adoption and region a l adaptability.
We also have to recall that, financial support to small
enterprise and serious individuals to set up effective
business operation in the biogas technology seemed to be
neglected. The private sector shows deterrence to invest
in biogas while input from big Enterprises is somehow
lagging behind due to the low in centive profits.
Moreover, lack of flexible community friendly credit
scheme to help poor farmers to own digester seems to be
another issue, while credit agencies aiming at making
profits are often reluctant for such kind of credit. This
may lead potential client to delay or even abandon his
investment decision. Certainly, there will be an immedi-
ate negative effect on the progress of biogas dissemina-
tion, if there are no appropriate measures to tackle those
kinds of probl em.
4.3. Lack of Information Sharing and Recent
Research Information on Biogas Technology
A few number of research works on biogas technology
can be found on internet, but it is quite difficult to know
what is going on at national levels. Lack of data collec-
tion, evaluation and information sharing is regarded as a
barrier to anaerobic digestion technology in Africa. The
numbers of reports for some institutions remain confi-
dential and gathering information action is hampered by
some procedures. Furthermore, research engagements are
not yet fully adopted by academicians and government
institutions sometimes due to lack of funds or roadmap.
These actually have negative impact on biogas dissemi-
nation and also obstru ct joint research programs between
developed countries and developing countries.
Thus, the possibility for technological transfer that
could rise up the technological mindset and satisfaction
of biogas users and implementers will be played down.
Despite the existence of a wide range of business oppor-
Table 1. Cost of 4 m3 digester in selected countries.
Country Bulk Construction Plumbing Appliances Labor Other Total in US$/4m3 digester
Rwanda 521.94 112.51 70.33 226.21 48.09 979.08
Cameroun 410.64 73.08 9.00 205.10 - 697.82
Kenya 359.10 63.54 68.00 174.73 - 665.37
Tanzania 364.39 71.84 50.00 163.16 5.26 654.65
Burkina Faso 300.86 48.09 45.73 144.82 60.98 600.48
Senegal 251.33 51.72 73.17 186.05 22.10 584.38
Uganda 283.99 49.33 37.33 90.00 94.32 554.97
Source: Cost re duction 2010, National Dome stic Biogas Program, NDBP-Rwanda.

C. MULINDA ET AL. 511
tunities in rural areas in Africa, experience has shown
that local entrepreneurs have not yet taken advantage of
such opportunities due to lack of capacity and resources
to develop a robust business plan of research works.
4.4. Political and Security Issues
Some assumption pointed out that security threat in Sub-
Saharan Africa may be also one of the causes that slow
down the biogas technology dissemination. The different
regions of Africa shelter internally displaced persons and
refugees such as DR Congo, Uganda, Kenya, and Soudan
among others. People from unsecured areas are often
hesitant to invest in long-term projects. These insecurity
problems are sometimes linked with food security crisis
that overwhelms economic development at various levels
and may cause direct or indirect effect on biogas tech-
nology.
4.5. Biogas Technology Pilot Phase Failure
Demonstration and pilot phase in Africa took place about
four decades ago but, it is reportedly said that most of
digesters constructed during that period showed various
malfunctions that disrupted biogas dissemination cam-
paign [19]. The technology required some skills, social
acceptance and mind set for reliable operation, which the
beneficiaries lacked. Moreover, a lot of biogas plants
were individual demonstration plants which were not
really wanted by the users, but were more tolerated. Con-
sequently traditional sources of energy continued to be
preferred, henceforth the benefits of biogas technology
has not been capitalized .
5. Conclusion
The need to benefit from African biomass resources is
fully justified by low electric distribution, alarming de-
forestation and the pressing use of clean energy and sus-
tainable environment. Considering the role, importance
and contribution of biogas technology to the welfare of
people, especially those with low income and present
dissemination rate, there is a wide gap to overhaul. Be-
sides, the biogas dissemination will have to go beyond
some hitches like high investment cost, political and se-
curity issues together with pilot phase grievances to en-
sure that marketable biogas technology has been put in
place. There is a need to fully engage and speed up dis-
semination of biogas digesters by designing specific
policies, full support and promotion of anaerobic diges-
tion technology. Granting subsidy and supporting rural
communities to develop biogas industries may seem as
milestone since it would lead to job creation, husbandry
industries and finally, improve rural people’s livelihood
in Africa.
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