(pic: cooking on biogas in Nepal)In the first of a new series, Carla Jones highlights some impressive biogas projects in Asia and Africa.
The way biogas works is quite simple: take an airtight container (usually a brick chamber under the ground), fill it with some organic matter (manure, human waste or kitchen waste are the most common), and let the bacteria break it down. What comes out is biogas, that can be burned for cooking. The residue is a nutrient-rich fertilizer for crops.
Typically, a single fixed-dome biogas system is made from brick and sits underground. Many of our winners, though, have taken this design further. VK-NARDEP
has developed a small bamboo-framed model, ARTI
has designed a ‘balcony’ digester for apartments, and KIST
in Rwanda has built a system of five interlocking chambers.