There are issues surrounding the lack of willingness to finance biodigester projects at all scales in many SSA countries particularly at the household level, lack of financial arrangements for poorer households where technology is most viable, prevailing climatic conditions beneficial but socio-economic conditions (particularly availability of feedstock and financial capacity of rural users) can be problematic.
Household-scale biodigesters can be an effective solution to providing thermal energy services to rural poor communities in the developing world. However, successful examples of biodigester programs in the past at a government or development-agency scale have mostly been confined to China, India and South-East Asia more widely. Notably, there has been a distinct lack of experience of successful biogas projects in Sub-Saharan Africa. The STEPs research project aims to address some of the reasons behind this, and propose potential solutions.
In theory, the prevailing conditions in Sub-Saharan African countries are mostly beneficial for the introduction of biogas digesters. Climatic conditions, on the whole, are suitably warm, with minimal cold periods to impact digester efficiency. In addition, target users are in abundance in rural areas, if considering the local feedstock regime. Small cattle farming is prevalent in a number of SSA countries, and subsistence farmers in rural areas often keep a small head of cattle. Given also the distributed nature of rural populations in a number of SSA countries (particularly, for example, in Eastern South Africa), household-scale biodigesters are an excellent solution for providing thermal energy services to households.
Potential uses for biogas and waste products. Sovacool, Kryman & Smith (2015) Scaling and commercializing mobile biogas systems in Kenya: A qualitative pilot study. Renewable Energy, Vol. 75, pp 115-125, http://dx.doi.org/10.1016/j.renene.2014.10.070
However, the lack of successful experience of biogas dissemination programs or businesses can be attributed to a number of factors, first and foremost of which is the cost of biodigesters (ranging from US$30 for a rudimentary drum-type system to over US$700 for a larger household system) [1] [2], and the lack of credit facilities/service regimes to enable access to the technology for the poorest consumers. Biodigester technology still represents a significant upfront cost to a typical rural household, and micro-credit services for clean energy technologies are still in their infancy in SSA countries, with some successful experiences in countries like Kenya or South Africa for solar home lighting or electricity systems in Kenya for example, but little widespread knowledge.
This lack of end-user credit is mirrored in a general lack of energy service companies or institutions offering biodigester services, with the cost issue again a driving factor behind this. Given how critical the maintenance factor is in biodigester installations (an issue which will be explored in the next blog), this lack of service companies, integrating credit or fee-for-service business models with a maintenance and servicing regime, has hampered uptake significantly in the region. The final negative factor is in fact the converse of an advantage: whilst some households will have suitable feedstock availability, compared to average heads of livestock or agricultural waste availability in South-East Asia, SSA has a much lower proportion of households with viable feedstock availabilities. Targeting consumers and areas where feedstock regimes are good is a critical step in ensuring the success of programs or business around biogas digesters in SSA.[2]
The next post in this series will investigate maintenance of biodigesters, and the necessity of maintenance and service arrangements with end-users to ensure efficient and successful operation of biodigesters.
– Xavier Lemaire & Daniel Kerr, UCL Energy Institute
[1] Hojnacki et al, MIT (2011) Biodigester Global Case Studies. Available at: https://colab.mit.edu/sites/default/files/D_Lab_Waste_Biodigester_Case_Studies_Report.pdf
[2] Raha, Mahanta and Clarke (2014) The implementation of decentralised biogas plants in Assam, NE India: The impact and effectiveness of the National Biogas and Manure Management Programme. Energy Policy, Vol. 68, pp. 80-91
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