The Flexi Biogas system is a flexible above-ground biogas system manufactured in Kenya that is simpler and less costly to build and operate than traditional fixed dome biogas systems. It consists of a plastic digester bag housed in a greenhouse tunnel. Organic waste placed in the bag produces biogas through anaerobic digestion, which is then piped to appliances. The Flexi Biogas system is portable, inexpensive at $410, and takes only one day to install compared to $1,000 and 21 days for fixed dome systems. It also has a shorter retention time of 15 days versus 45 days.