How human waste can protect Malawi’s forests - BBC Future
▻https://www.bbc.com/future/article/20210420-the-underappreciated-power-of-human-poo
At Mulanje Prison in southern Malawi, convict Felix Chimombo wakes up early every morning to prepare food for his fellow inmates. With a handful other prisoners, Chimombo’s responsibility is to make sure that by 7:00 AM, they have prepared food for 200 or so inmates at the prison. The prison previously used an average of two cubic meters of wood to prepare the day’s food, an arduous process that could last for five hours.
But then came a rather unconventional replacement for the wood. The prison was installed with a biogas digester, a system that converts organic matter – including human waste – into energy. Made from plastic sheets, the system has an inlet that feeds the poop and other waste into a digester, where they are submerged in water. The water creates an anaerobic environment that allows bacteria to break down the biomass into methane, which is pushed through a piping system to the gas stoves in the prison’s kitchen.
via @reka