Waste into Energy in Africa

Students at the MIT Sloan School of Management have drawn up a business model for a company called Sanergy (it begins with sanitation and ends with energy). The idea is to build a network of "sanitation units" in Kenya, collect and process the waste, and then convert it into energy and fertilizer. 

Social and environmental challenges, such as, demolition, health emergencies, a lack of a social safety net, and flooding in the rainy season are all frequent occurrences in the informal settlements. The consequences of these events are devastating. Sanergy is social enterprise which provides solutions to the sanitation-related diseases in Africa’s slums by making sanitation accessible, affordable, and sustainable.

The first part of the model is to build, and franchise a dense network of low-cost sanitation centers, eventually expanding to every block of the slum. Each center will provide basic high-value services: hot showers and clean toilets. Having a small footprint and low cost to construct, each center is designed to service a customer base of 77 people.

These centers will be franchised to local entrepreneurs with direct financing from a local microfinance bank, and the day-to-day operation of the facility. The franchisees earn income through pay-per-use fees, membership plans, and sales of complementary products to toilet users. The income generation potential is a natural incentive for the franchisees to maintain the facilities and provide good customer service.

Rather than septic tanks, pit latrines, or sewer systems, the Ecosan system used in the sanitation centers deposits the waste in air- tight containers. These containers of urine and feces are collected on a daily basis by a waste collector using handcarts. Each day, Sanergy employees collect the full containers of waste from our operators and provide them with clean empty containers. The containers full of waste are brought to our central processing facility.

The processing facility will efficiently convert human waste into biogas through industrial-scale anaerobic digestion process. By centralizing the processing of waste, the yield of the conversion process can be significantly increased through economies of scale when compared to small household and village level biodigesters. The biogas will be combusted in CHP engines to generate electricity that will be sold directly to the KPLC and the national grid through long term power purchase agreements. Finally, the output from the biogas generation will be processed into high-quality organic fertilizer, which will be sold to commercial farms and small hold farmers.

The long term objective is to build and scale viable sanitation infrastructure in the slums of Nairobi. The model involves four parts:
1. Building a network of low-cost sanitation centers in slums
2. Distributing them through franchising to local entrepreneurs
3. Collecting the waste produced
4. Processing it into electricity and fertiliser. At each step, this model creates jobs and opportunity while simultaneously addressing serious social needs