In the slums of the Kenyan capital, Nairobi, visiting the bathroom usually means one of two things; a trip to the local pit latrine or the ‘flying toilet’.
The former entails letting nature take its course in a rickety outhouse perched atop a hole in the ground—a facility also used by hundreds of other people in the neighborhood.
The latter meanwhile consists of relieving oneself in a plastic bag before throwing the offending item away in the street.
A 2011 report by the Bill and Melinda Gates Foundation found that these arrangements led to environmental contamination and the spread of diseases such as typhoid and tuberculosis.
But within this primitive sewage system recent MIT graduate, David Auerbach, has spied an opportunity he believes could one day be worth millions of dollars.
Alongside a group of fellow MIT alumni and local Kenyan partners, Auerbach has helped found Sanergy—a start-up that aims to make a business out of cleaning up Nairobi’s sanitary mess.
It plans to collect human waste in a series of custom-built toilets before transforming it into compost and fertilizer products that can be sold to the local agriculture industry.
The Sanergy model works by first installing a network of low cost sanitation centers, which provide access to clean toilets, at various locations in the slums.
These premises—that trap the waste in air tight containers—are then franchised out to local entrepreneurs at a cost of 45,000 shillings (roughly $500) a year, with a renewal fee charged to continue after this period.
Franchisees are funded primarily by micro-finance loans, explains Auerbach. They charge residents a small fee, usually 5 Kenyan Shillings ($0.06) to use their facilities in order to make their money back.
The waste is processed and broken down to be transformed into a variety of organic fertilizer products that are then sold on to commercial farms.
“Currently we have 25 facilities up and running . . . we’re collecting about three metric tons of waste per week which can all be converted into fertilizer,” says Auerbach.