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The biogas plant in Kenya is converting waste into biogas to provide energy
Eliminating energy poverty and cutting carbon emissions at one go; that’s exactly what Africa’s first grid-connected biogas plant is doing. A power firm in Kenya is using waste from vegetable and flower production and converting it into biogas to provide energy to country’s electricity network.
The Gorge Farm Energy Park in Naivasha is selling surplus electricity to the national grid, hence, reducing the carbon emissions associated with oil-fuelled power generation. Currently, it produces 2 megawatts (MW) of electricity—more than enough to cultivate its 706 hectares (1,740 acres) of vegetables and flowers. It also produces surplus to meet the power needs of 5,000-6,000 rural homes.
The new plant generates not only electricity, but also heat for the farm's greenhouses, with fertiliser as a by-product.
Located about 76km (50 miles) northwest of Kenya's capital, Nairobi, this Gorge Farm is owned by the Vegpro Group, a leading exporter of fresh vegetables in East Africa. The plant is operated by Biojoule Kenya, an independent power producer that signed an agreement to sell electricity to Kenya Power & Lighting Company (KPLC)—Kenya’s only power distributor.
While diesel-generated power costs $0.38 per kilowatt hour (kWh) to produce, Biojoule Kenya sells power to Gorge Farm and to KPLC for $0.10 per kWh. The plant is not only producing clean but also cost-effective power for the people of Kenya by using locally produced feedstock.
Carbon emission reduction
The biogas is produced by the plant through anaerobic digestion, a process wherein crop residue from the farm is digested by micro-organisms. The biogas produced is then burned in two engines leading to cogeneration—producing both electricity and heat.
It would have required 5 million litres of diesel annually to produce the same amount of energy.
According to Tropical Power, a developer of biogas and solar plants that supplied engines to the Gorge Farm Energy Park, this biogas plant contributes to a 7,000-tonne reduction in carbon dioxide emissions each year.
Potential for biogas-generated electricity
Helen Osiolo, a policy analyst at the Kenya Institute of Public Policy Research and Analysis, believes that biogas could generate between 29 and 131 MW of power, but the challenge is to make the government pay enough for it.
Two immediate challenges that confront the biogas sector are tariff and availability of fertilisers. Firstly, the tariff is too low to attract investors’ interest. Secondly, agricultural and municipal waste is in demand for other uses like fertiliser. This may limit the expansion of biogas generation.
Recenetly, an NGO in Kenya came to limelight for converting faecal sludge into biogas.