Blue Flames and Golden Fertilizer: A great opportunity for Kenya’s circular economy

The United Nations Environmental Program (UNEP) estimates that annually 14,300 people die in Kenya from exposure to household air pollution, because of cooking on open fires or traditional stoves. Traditional domestic energy sources for cooking and lighting are mainly based on biomass (wood, charcoal) and these sources are rapidly diminishing. Moreover, the Food and Agriculture Organization (FAO) estimates that 33% of world soil is moderately to highly degraded due to erosion, nutrient depletion, acidification, urbanization, and chemical pollution. Kenya is no exception with over 12mln people living in areas with degraded lands.

> Click here for the Dutch version

Green Energy

Bio-digesters essentially convert organic waste matter into combustible methane. Using biogas as cooking fuel, bio-digesters reduce dependency on firewood and charcoal for rural households. Households with just three cows or seven pigs can generate sufficient gas to meet their basic domestic and/or productive energy needs: clean cooking/heating and basic lighting. 

Koken op biogas

The use of biogas helps reduce indoor air pollution and consequent health hazards such as lung and eye diseases, and decreases deforestation and greenhouse gas (GHG) emissions. Further, it increases the safety, productivity and incomes of households, benefitting women in particular.

Bio-slurry, the process residue, can be used as a potent organic fertiliser to enhance agricultural productivity and sustain soil fertility. Crops assimilate the nutrients in bio-slurry easier than from raw manure, thus increasing productivity on average by 25% while improving the structure and water retention capacity of the soil.

Bemesting met bio-slurry

Closing the nutrient cycle

Increasingly, and in particular in developed countries, the production of animal feedstock and food products is based on nutrients originating from “foreign soils”, depleting their organic matter and nutrient content.

“It is essential to work towards achieving a circular economy, where nutrients are as much as possible re-circulated in the cycle. Kenyan dairy farmers who have bio-digesters are increasingly closing the nutrient cycle by using bio-slurry to fertilise their fodder crops, providing a higher quality and quantity of feedstock for their dairy cows, which in turn will result in a higher quality and quantity of milk production.”

An average-sized household bio-digester in Kenya will produce approximately 600 cubic metres of biogas per annum (6 tonnes of gas), and 30 tonnes bio-slurry (with 15 tonnes of organic waste, manure, and 15 cubic meter of water) which can fertilise at least 1 hectare of arable land. Farmers can also use the bio-slurry to make compost which then could fertilise up to 3 hectares. Excess bio-slurry and/or compost is increasingly being sold to fellow farmers who are aware of the potency bio-slurry/compost has for improving their soils and the crops they grow. The use of a digester will substitute on average 6 tons of biomass based fuels, and about 200kg of mineral fertiliser, while mitigating greenhouse gas emissions with 4 tons of CO² equivalent per digester per year.

Biogas is becoming increasingly popular as the farmers earn back their financial investment in a bio-digester in less than 2 years on average. This is due to the fact that small farmers spend less money on charcoal and firewood. The prediction is that the total market for household bio-digesters in Kenya is  1.64 million households [1]. This demonstrates that there is a huge potential with many opportunities for for accelerated development of Kenya’s circular economy.

UN Sustainable Development Goals

The Africa Biogas Partnership Programme (ABPP)

ABPP is a Public Private Partnership between Hivos, SNV and the Directorate General for International Cooperation (DGIS) of the Dutch Ministry of Foreign Affairs. The ambition of the programme is to make bio-digesters the preferred farmer solution in Africa for clean cooking and higher agricultural yields.  The programme intends to achieve this objective by focusing its work in each country on 4 different pillars: (1) demand, (2) supply, (3) innovative finance and (4) the enabling environment.

In 2017 more than 60,000 biogas digesters have been constructed in the five ABPP countries (of which 18,000 in Kenya), providing 300,000 people access (90,000 in Kenya) to a sustainable source of clean renewable energy and natural fertiliser, directly contributing to UN Sustainable Development Goals as per the figure on the left.

Biogas and other technical innovations are welcomed with open arms in Kenya. Biogas is one of the many innovations that can result in wonderful business opportunities for (Dutch) business, from biogas installation to bio-slurry Kenya is ready! We are aware that there is a large variety of innovations and therefore we encourage companies to share their stories with us and our readers. We open our website for you, would you like to share the story of you company? Please send an email to and we can discuss the possibilities.

[1] households that hold improved dairy cattle in (semi) zero-grazing regimes