And before you ask   no, it doesn’t smell. A Kenyan public company has found a way to manufacture human waste into fuel briquettes that can be used for cooking and heating in the home.

The poo briquettes actually fulfil two functions: not only are they an efficient and safe source of fuel, but the collection of the waste needed to make the briquettes has also improved sanitation in towns and villages.

The process used by Nakuru Water and Sanitation Services Company (NAWASSCO) starts with human excrement, collected from pit latrines and septic tanks around the region of Nakuru, north west of Nairobi. The waste is then taken to a processing plant, where it is dried out for two to three weeks in drying beds in a greenhouse. The hot temperatures in the greenhouse take out around 70 per cent of moisture from the sludge, which prepares it for carbonisation.


Briquettes being used in fires. Photo: Nakuru Water and Sanitation Services Company

The dried waste is then heated in a kiln at temperatures of about 700 to 800 degrees Celsius, which burns off harmful gases (and the smell). It’s ground up finely, before being mixed with sawdust that has also been carbonised. Molasses are also added at this stage to bind the materials, and it is formed into little balls.

Briquettes being formed in the rotating drum. Photo: Nakuru Water and Sanitation Services Company

Briquettes ready for packaging and sale. Photo: Nakuru Water and Sanitation Services Company

Cooking a local meal with the briquettes. Photo: Nakuru Water and Sanitation Services Company

The combined materials of milled sawdust and sludge are fed into a rotating drum machine, while molasses (a binding agent) are added gradually until the mixture forms a ball of about 2.5 cm in diameter. Photo: Nakuru Water and Sanitation Services Company

Reuters reported that there was slow uptake of the product at first, because of the stigma of human faeces, but locals are now convinced. France 24 spoke to a local who prefers this new type of fuel, after initial scepticism of the idea.

“They’re easier to light, and stay lit longer”

Isaac Wafula is a tuk-tuk driver who lives in the Nakuru region. He and his wife recently started using the briquettes.

When I first heard about the idea, I thought it was really funny – I didn’t understand how they are able to transform it. I was one of the people who criticised it and didn’t bother testing it because I thought it wouldn’t be good. Then I saw them for the first time at a neighbour’s house. Now I think these briquettes are better than others.


Normally I use kerosene for cooking, but I use these briquettes when food takes a long time to cook. For example, we use it when we cook beans, and my wife uses it to cook French fries that she sells. These briquettes are much easier to light, and they stay lit longer than coal. So they are good but they are a little expensive for me.

People have started selling them everywhere in Nakuru; if I want them I can find them easily. One package of them costs 65 Kenyan shillings [0.53 euros].

Meat being cooked over the briquettes. Photo: Nakuru Water and Sanitation Services Company

From left to right, Internal Audit Manager Joseph Githinji, Site Manager John Irungu, and NAWASSCO's Managing Director Eng. James Ng'ang'a viewing the drying briquettes

“The briquettes are also helping with sanitation and pollution problems”

Reinilde Eppinga, an advisor for SNV Netherlands Development Organisation, which partnered with Nakuru Water and Sanitation Services Company for the project, says that they’re hoping to increase production of the briquettes from the current two tonnes a month to ten tonnes a month and eventually ten tonnes a day.

The product has become popular, and we’re creating awareness campaigns so that people know about it. The briquettes are being used in hotels and restaurants for cooking and space heating, in schools, in people’s houses, and by poultry farmers who use them to warm breeding houses for hens.


Inspection of the output of briquettes. Photo: Nakuru Water and Sanitation Services Company

The selling price is comparable to that of ordinary charcoal but the benefits surpass charcoal and firewood, in terms of money saved [because they last longer] and also the health benefits [because the poo briquettes produce less smoke].


Cooking over the briquettes. Photo: Nakuru Water and Sanitation Services Company

Collection of human waste is also helping to deal with sanitation problems in Nakuru. In low income areas, the collection of sludge is challenging because of the types of constructions and terrain. Many residents have constructed pit latrines, which are difficult to empty because they have not been lined properly and so there is a danger of them collapsing. Some areas do not have road access for exhauster trucks to get through. But now NAWASSCO, in collaboration with Nakuru County Public Health Department, has an onsite solution: pits in low income areas are manually emptied by certified workers. Now residents can have their pits emptied safely and hygienically, whereas before people would empty their own pits at night, burying the waste anywhere or leaving it in drainage systems.


Only one out of every four residents in Nakuru has access to the town’s sewage system, and so poorly disposed of waste was polluting the environment, with harmful pathogens entering Lake Nakuru. Eppinga says that apart from providing solutions to environmental concerns and creating a use for a waste material, the briquettes could also have a direct economic benefit in the future: if the business continues to develop, “it may generate income for jobless youths in the country while providing clean and affordable sources of fuel for large populations.”


Thanks to Clebert Bigirimana for his help reporting this piece.


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Article written with
Catherine Bennett

Catherine Bennett , Anglophone Journalist