The secret power of human waste that can save forests
Felix Chambo, an inmate at the Malanje prison in the southern African country of Malawi, gets up early in the morning and prepares food for his colleagues. Together with a few inmates, Chambo is responsible for preparing food for about 200 inmates by 7am.
In the past, the prison used an average of two square meters of wood for cooking a day, and the process took about five hours.
But then an unusual alternative to wood was introduced. The prison is equipped with a biogas plant digest system that converts organic matter, including human waste, into energy. This system made of plastic sheets has an entry point into which waste is dumped and submerged inside the machine.
This water is intended to create an anaerobic environment in which bacteria convert biomass to natural gas methane. This gas is sent through pipes to run stoves in prison kitchens.