Sanitation woes are helping to fuel green energy in Kenya's largest slum, where human excrement is being transformed into an asset.
Kenya's growing urban population has made it difficult for the government to tackle sanitation, with an urgent need for innovative solutions.
In Kibera slum, seven kilometres from Nairobi, human waste is being turned into biogas thanks to initiatives supported by the community, the Health Ministry and others.
Tree Hill School is one of nine bio centres – sanitary blocks that use a biodigester system to treat waste and produce biogas – that has been opened.
It has backing from the Umande Trust civil society group and other partners including the French Development Agency.
Benazir Douglas, of the Umande Trust, said her team looked for ways the community could make money from efforts to make their surroundings healthier and safer. Using readily available items, such as fecal matter, made sense.
"They not only collect money from the sale of biogas but also through a small fee from members of the public who use these toilets," she said.
Teachers, locals on board
Tree Hill teacher Rose Muthoni said enrolment had increased since the bio centre's opening had spurred a food program and improved sanitation conditions. However parents were reluctant at first.
The school previously had only two toilets.
A neighbouring grocer, James Kariithi, said he often visited the bio centre.
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