By Virginia Nyambura
Biogas refers to a type of biofuel naturally produced from the decomposition of organic waste. Organic waste such as food and animal waste breaks down in an environment without oxygen and release a blend of gases namely carbon dioxide and methane.
A biogas digester must resemble the stomach hence, must have an inlet, an outlet and the ability to stir the materials as it grids them.
There are normally three designs of biogas plants, the floating drum, fixed dome, and a flexible bag. The fixed dome and the floating drum plants have all the qualities of a stomach which make them more long-lasting than the flexible bag designs.
The fixed dome plant design, however, is famous for its ease of the day to day operation, low operating expense and the ability to produce gas regularly on a daily and annual basis despite the climate conditions varying. This type of biogas unit, if constructed by a qualified and experienced technician, can last for as long as 50 years making it recommendable.
Zeddy Rotich, a coffee farmer from Kericho County, explained to CNN how she uses cow dung to power her biogas stove. Zeddy noted that she was faced with challenges to get dry firewood, especially during the rainy season, this hence pushed them to come together as a group of three hundred women to construct biogas units, at least ten every year.
“It produces clean energy. It does not produce soot, and even my silverwares are stainless compared to the other older type of energy where I used to cook using wood fuel. As it is a government regulation not to fall down trees, it is so hard to get even firewood to cook and you have to cook for the family. Nowadays I don’t even use wood for cooking. Because initially I used to wake up early in the morning and collect firewood fast, and it will consume a lot of time. And that one also means I go to my coffee farm very late hours after taking a lot of time collecting firewood,” Zeddy stated beaming with pride.
“In the morning I wake up, feed my cows. And in turn they give me cow dung, after collecting the cow dung; I put it into the mixing chamber. Then I add water at a ratio of 1 to 1, thereafter, I drain the mixture into my digester from where I can easily get my biogas,” Zeddy explained.
Zeddy Rotich encouraged other homesteads to adopt the biogas units stating that it is also environment-friendly and the advantages outweighed the disadvantages.