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14 декабря, 2021
As indicated in Table 3, there are some digesters have been installed in a number of subSaharan Africa. These have mainly been pilot or demonstration projects aimed at testing the technical viability of small-scale biogas technology at a limited scale (Hivos, 2009a). These pilot projects have mostly been funded by non-governmental organizations and built for health clinics, schools, and small-scale farmers. While the small-scale biogas plants are located throughout Africa, only a few of them are operational (Parawira, 2009). There is also limited documentation on whether the existing biogas digesters have been successful in achieving the benefits highlighted in section 3.1. Some country specific examples is Tanzania, Ivory Cost and Burundi, which have produced biogas from animal and human waste using the Chinese fixed-dome digester and the Indian floating-cover digester (Omer and Fadalla, 2003). These have not been reliable and in many cases, poor performance has been reported (Omer and Fadalla, 2003). Thus, the plants have only operated for a short period due to poor technical quality (Mshandate and Parawira, 2009).
Currently, a number of different organizations are establishing biogas initiatives in Africa, particularly in rural areas, in order to supply cleaner burning energy solutions. These initiatives are at different stages of development such as: prefeasibility, feasibility, design and implementation to a limited extent. For instance, Burkard (2009) reports on five biogas case studies in Kenya which were to utilize agricultural leaves, residues from floriculture, and residues from vegetable production and canning. In 2010, it was reported that the Dutch government was to spend 200 million Kenyan Shilling to set up 8000 biogas digesters throughout the country. The initiative was targeting farmers practising zero grazing (Daily Nation, 2010). Similar projects are being implemented in Ethiopia, Uganda, Senegal, Burkina Faso, and Tanzania. There are also some other initiatives such as biogas for better life, which is at various stages of biogas development in Ethiopia, Kenya, Uganda, Sudan, Zambia, Malawi, South Africa, Lesotho, Swaziland, Mali, Senegal, and Ghana1. The Netherland Development Organization (SNV) has been supporting the development of National Biogas programmes in East Africa (Ethiopia, Kenya, Uganda, Tanzania, Rwanda) and West Africa (Senegal and Burkina Faso)[3] [4]. While there are few documented successful small-scale biogas plants in the rural areas of Africa, this section will present some selected country specific biogas projects.
Rwanda has a population of 10.2 million people of which 81% of this population reside in the rural areas in 2010 (United Nations, 2007). One of the famous biogas programmes is the Kigali Institute of Science and Technology (KIST) large-scale biogas plants developed and installed in prisons. The aim of these plants was to treat toilet wastes and generate biogas for cooking. The first plant prison which was operational in 2001, and by 2011, KIST has managed to build and operationalize biogas plants in 10 prisons. Each prison is supplied with a linked series of underground biogas digesters, in which the waste decomposes to produce biogas. After this treatment, the bio-effluent is safe to be used as fertiliser for production of crops and fuel wood. The project was funded by Red Cross and the plant consists of five interlocking chambers. KIST’s project saves 50% of wood for cooking and it won Ashden Award in 2006. The projects construction is managed by KIST, who also provides training to both civilians and prisoners.
Another biogas programme is the National Biogas Programme which is promoted by the Rwanda Ministry of Infrastructure, through the support by the Netherlands development organization. The programme aims at reducing firewood use by the households. The Ministry of Infrastructure estimates that 441 units have been installed to date, and approximately 15 000 households will be using biogas by end of 2011 for cooking and lighting[5]. The Ministry of Infrastructure of Rwanda is also collaborating with other ministries (e. g. Ministry of Education) in order to develop biogas plants in schools, clinics and community institutions.