With 25 kilos of cow dung, you get cheap cooking gas

Rehau Home Gas is a low maintenance unit made up of a cylindrical, mini-biogas unit running on cow dung and water

It is the desire of every household to access cheap and clean energy. That is a reality now. Researchers from Jomo Kenyatta University of Agriculture and Technology (JKUAT) have developed a cheap and reliable form of energy that will cut use of firewood.

The Rehau Home Gas is a low maintenance unit made up of a cylindrical, mini-biogas unit running on cow dung and water.

To power, it only needs 25 kilos of cow dung mixed with 25 litres of water per day to give more than four hours of continuous clean cooking gas.

“Rehau home gas is designed for rural and semi-urban households. The equipment is made using a special black polymer material imported from Germany, capable of withstanding UV light and tropical weather conditions,” says Eunice Auma, the projects manager at JKUAT.

How gas is produced

The project was launched in 2015 by a team of engineers from JKUAT and Germany to empower small scale dairy farmers on how to make use of cow dung which is a waste matter on most farms.

According to Auma, this technology is the most effective way of producing cooking gas with 80 per cent production efficiency.

“The digester uses cow dung from four to six cows. But the dug from one cow can be enough to produce gas that can be used at home for a whole day. It depends on amount of cow dung your cows produce,” she says.

The researcher explains that production of the gas starts once the cows excrete the dung. After they produce the dirty waste, the farmer cleans the cowshed and mixes the dug with water.

Next, the farmer feeds the mixture into the digester through the 6 meters long feed stock in-let that lets in the mixture into the digester.

When the mixture is fed into the digester, anaerobic reaction takes place and the gas is produced. Later, it is stored in the normal storage bags that are made of PPI material which can store more than 3 cubic metres of the gas.

Installed at JKUAT

She explains the process: “It only takes four hours for the anaerobic digestion to take place once the dug is fed into the digestion bags and in the absence of oxygen, bacteria works on it to produce this cooking gas,” says the researcher.

Since the Rehau home gas was invented, it has received positive reviews.

The system is locally assembled at JKUAT’s Agricultural Engineering workshop in Juja. It can be distributed throughout the country at the clients cost.

The system costs Sh58,000.