More research needed to tap Africa's biogas potential
Lack of local research is preventing countries in Sub-Saharan Africa producing energy from waste, according to a report.
The region has abundant raw materials for producing biogas. Waste and polluted water from industry — including slaughterhouse remnants, animal dung and sewage — can be converted into carbon dioxide and methane through anaerobic digestion. The biogas can be used for cooking and vehicle fuel, and the waste product as a fertiliser.
But a recent assessment of efforts to research and apply biogas technology says production plants are not widespread because biogas research is impeded by poor infrastructure, a lack of human resources, and a lack of funding for the purchase and maintenance of essential equipment and running costs.
"Biogas production can provide high-quality organic fertiliser for use in fields, increasing yields," says co-author of the research Anthony Mshandete from the University of Dar es Salaam in Tanzania.
Such units also reduce the risk of pollutants contaminating rivers and landfills and lower the demand for wood and charcoal, both of which are implicated in climate change and respiratory illnesses, he told SciDev.Net.
The technology to produce biogas for farms and households has been in use in Africa for three decades but high maintenance costs are restrictive, says Mshandete.
Smaller plants, which typically power households or schools, can be of ''poor technical quality'', are ''not reliable and have poor performance in most cases'', the report found.
These smaller plants, found in many countries including Burkina Faso, Ghana, Lesotho, Morocco, Nigeria, Senegal, Tunisia, Uganda and Zambia, were often installed by nongovernmental organisations.
Instead, the authors recommend investment in large-scale fermentation plants which can take more than 100 cubic metres of waste at a time, as found in Botswana, Cote d'Ivoire, Egypt, Ethiopia, Malawi, Rwanda, South Africa, Tanzania and Zimbabwe.
For example, a pilot project running since July 2006 in Tanzania's Korogwe district can yield 150 kilowatts of electricity from sisal waste, enough to provide power to a rural community, says Mshandete.
But researchers must determine which locally available materials are most appropriate to fuel such plants and investigate how to optimise the process, say the authors.
For this they suggest joint research programmes between African and developed countries, which should also explore technology transfer.
The review was published in the African Journal of Biotechnology in January.