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Money for bioslurry: how to improve the commercial viability of Benin’s national biodigester programme


Oroua Saadou and his brother Sisi are farmers from Gbakayèrè, a remote rural area in north-east Benin, 325 miles from the capital city of Port Novo. Together with their 6 wives and 17 children, they grow corn, sorghum, rice and cotton on their 10 hectares of land. They also breed cows which they sell as livestock.

Oroua’s family has recently installed a biodigester on their farm: an airtight tank in which organic materials mixed with water are ‘digested’ through anaerobic microbe action to produce biogas for cooking and lighting.

The women in our house are responsible for cooking food and go through a lot of pain, every day, to collect firewood, which is increasingly hard to find. They also spend all day preparing meals on open fires. As a result, their eyes are red and their lungs are always congested,

says Oroua.

Most people in rural areas of Benin, about 80% of the population, face similar challenges to Oroua as they depend on firewood for cooking. With forest areas cut by roughly 210,000 hectares each year for fuel and farming, the country’s wood reserves and its precious biodiversity are under threat. Farming communities are also increasingly affected by climate change-related droughts and flooding, which disrupt growing cycles and yields.

In November 2020, with funding from the Swedish Postcode Lottery Foundation (SPLF), Energy 4 Impact teamed up with Netherlands Development Organisation SNV and Beninese NGO ALAFIA, to support the development of the biodigesters sector through a market-based pilot project, which aims to improve the economic viability of Benin’s National Biodigester Programme.

As a predominantly agricultural country, with agricultural waste largely unutilised, market potential for biodigesters development in Benin is high. In its outline for a National Biodigester Programme, the Government of Benin estimates that a minimum of 150,000 systems could be installed across the country.

The government recognises the potential of domestic biogas for addressing the current deforestation problem and reducing rural energy poverty, so it has committed to boost the adoption of clean cooking solutions from 15% in 2015 to 30% by 2030. However, it has estimated that €13 million will be required to develop the first phase of its National Biodigester Programme .

The current approach by the government is based on heavy subsidies, amounting to 40% of the investment cost, assumed to be €850 per biodigester (including the fee for construction and after-sales service). Concerns around the technology’s economic viability are making it more challenging for the government to raise funds from external donors to support its implementation.

The Energy 4 Impact-led project, Piloting Biogas in Benin towards National Scaling, intends to demonstrate that the biodigester market can be scaled-up if it is driven by the economic opportunities offered by the bioslurry, a by-product of the biodigesting process that can be transformed into organic compost.

“Although the National Biodigester Programme was designed in 2012, the programme has not taken off because the government’s subsidy approach requires financial resources which it does not currently possess”, says Anick Kemonoudavo, Energy 4 Impact’s Country Manager.

By focusing on developing the market for compost, our intention is to improve the commercial viability of digestors, and reduce the requirement for a government subsidy, making it easier for the government to promote a more efficient, more sustainable programme to donors.

The monetisation of the bioslurry can have a considerable impact on the technology’s affordability, which will eventually require minimal subsidies, making it economically viable. If the pilot performs as expected, it will provide a springboard for the fundraising strategy of the government’s National Biodigester Programme by showing this model can be replicated at scale.

Meanwhile, Oroua and his large family are amongst the first farmers to experience first-hand the benefits of their newly installed biodigester. Since it was built at the end of March 2021, the gas hobs are on for 10 hours a day to prepare meals and to heat up water for bathing the children.

Baké, one of Orua’s wives says:

When our husband told us we were going to install something which uses cow dung to produce gas for us to cook we all laughed. But then we said if such a thing exists, we commit to load it with dung and use it every day to cook, forget about the fire!

One day, Baké recounts, the masons arrived at the Saadou’s farm, bringing sand, iron and pipes. Orua and his younger brother dug a large hole and the women drew water to make bricks and gathered fresh dung. After the biodigester was built, it was loaded up with dung and water. Three days later, a plumber installed the gas stove and lamp in the kitchen, then Baké was asked to try out the new stove out. She put the water on and 10 minutes later it was boiling! The women all took turns to prepare a dish that day. “This is how we got a taste for cooking with biogas,” says Baké, “and we never turned back to using wood.”

What I personally like about biogas is that meals are cooked very fast, my utensils are always clean and there is zero risk of getting sick because there is no smoke. Since I no longer need to go look for wood, I have time to concentrate on other activities such as milking the cows, making cheese and selling it at the market in Kassakou,

Baké continues.

The women are even more excited at the prospect of generating additional income from the sale of the bioslurry, a commercial operation that they will oversee. It is estimated that each farmer household could produce up to 20 tonnes of bioslurry per year, using part of it for their own crops and selling the remaining part to generate €500-900 of turnover per year. In addition, easy access to bio-fertiliser is projected to result in at least 20% increase in yield and additional revenue for farmers.

The business model behind the pilot is quite simple: an initial grant from SPLF funds 80% of the cost of the biodigesters (about Euros 850 per unit) while the farmers cover the remaining 20%, mainly through in-kind contributions (labour and materials). Biophyto, a Benin-based company that produce organic agricultural inputs, will run the compost processing unit as a commercial operation: it will buy the bioslurry from the farmers and sell the resulting organic compost to interested farmers generating income that could fund the installation of more biodigesters.

Working with 120 smallholder farmers in Borgou and Alibori in Northern Benin, Energy 4 Impact with its partner SNV will be closely monitoring the costs and revenues at both the farms’ and the processing unit’s level, while also assisting with the marketing and sale of the organic compost.

Energy 4 Impact is now looking into developing a financial mechanism based on the compost value, whereby the businesses that sell the compost, in a future scale-up phase, could pre-finance the construction of new biodigesters for farmers, thus reducing the amount of subsidies that the government would have to pay otherwise.

Building on the data and lessons gathered during this pilot project, Energy 4 Impact will be able to advise the Government of Benin on the best course of action to modify its strategy for the highly subsidised National Biodigester Programme. It will facilitate the adoption of a market-based approach that delivers better and improved biodigester technologies, more developed supply chains, more enabling policies for investing in the sector, and more favourable conditions for smallholder farmers and businesses to access finance.

Having such a well-developed biodigesters programme in place could not only have a transformational impact on farmers’ and women’s livelihoods, it could also help mitigate climate change by preserving ecosystem biodiversity in Benin.