Newsflash: Human Feces Powers Rwandan Prisons

The feces or thousands of inmates at a Rwanda prison is being converted into combustible 'biogas' (methane gas) that can be used for cooking. It has reduced by 60 percent the annual wood-fuel costs which would otherwise reach near $1 million.

The Rwandan biogas facilities, which are currently in half of the 30 prisons around the country, now contribute half of the energy needs for cooking and lighting in each location. Rwanda's biogas facilities are among the most ambitious in the world - they range up to 1,000 cubic meters in something resembling a beehive shape. The process requires putting a given amount of human or other animal waste into a 'digester' which ferments it using bacteria to release methane gas that can be captured and then burned as fuel. Attached is a 'compensating chamber' that replenishes the supply of bacteria to keep the operation self-sustaining.

Wired News via Earthnow.org