By Brian Moseti
Among the common sights at homesteads in the Ewaso Kedong region of Kenya’s Kajiado County are mounds of manure, sometimes covered with tarpaulins or plastic bags.
Being pastoralists, members of the Maasai community who live in the area typically have many cows, goats and sheep, which overnight, generate tonnes of waste within their bomas (holding areas).
It is this waste that is commonly gathered and piled away for sale to buyers from other regions, who collect it in lorryfuls for as little as KSh1,000 thousand per load.
But the situation is different in Ene Moipei’s home where you cannot come across the telling mounds of manure, a resource he channels to produce biogas. Biogas is a biofuel that is naturally generated from the decomposition of organic waste.
When organic matter, such as animal waste, breaks down in an anaerobic environment (one without oxygen), a blend of gases comprising methane is released. It is this methane that is harvested as a clean fuel to power gas cookers and sometimes light fixtures.
The Moipei homestead has 23 cows and hundreds of goats and sheep, all of which produce enough waste matter to generate more gas than is needed every day, saving his family KSh8,000 per month in firewood costs. This is besides the added benefit of living in a smokeless environment.
“Like everybody else here, I used to sell this manure until I learned that it can be used to produce cooking gas,” said Moipei, 56, whose extended family comprises 17 members.
To produce the gas, Moipei collects the animal waste in two flexible digesters (tarpaulin bladders) each with a capacity of 6,000 liters and costing KSh87,000. About 20Kg of waste is added into each bladder daily to produce enough gas for the whole family.
“It is easy to maintain the system because all that is required is the once-a-day feeding of the system with fresh animal waste; nothing else,” said Moipei.
As the waste sits in the digester, decomposition happens producing methane that rises to the top and is then directed to where it is needed via pipes.
The digester is designed in such a way that once fresh matter is added into the bladder, expended waste is pushed out another end. The digested matter is free of smell but contains enough nutrients for fertilizing crops.
Presently, Moipei lets this effluent run through his farm as he works to set up an irrigated crop-production enterprise.
“Most of us who live here have plenty of land, but it is only now that we are learning to use it productively. I am planning to start watermelon farming and I am sure that the waste from my biogas system will come in handy to fertilize my plants,” he said.
For more information on the flexible biogas digesters, call Flexi Biogas Solutions on 0722700530 or email firstname.lastname@example.org