The Improved Biogas Systems Project: results and future work

A simple, batch-fed, improved biogas system under development in India may offer a number of advantages over conventional digesters. Compared with existing designs, the new systems are less costly, they can be constructed quickly in a few days using unskilled labor, they can digest any type of biomass, they require less water, labor, and dung, and they are easily repaired and moved. The IBSP design can be constructed on different scales, from meeting family needs to providing irrigation-pumping or a small village “utility”. These latter options could generate revenues to make them self-financing, without subsidies. Technical, economic, and organization aspects of the new design are discussed, followed by a review of next steps required for further dissemination. The work to date shows the need to move well beyond using scarce dung merely to provide families with cooking fuel. The new biogas design creates opportunities to use energy from available biomass to meet broader rural needs for irrigation, drinking water, cooling, and shaft power. Monthly user charges seem competitive with other energy technologies which do far less useful work. The costs of providing these services can be recovered through local organizations without depending on complex bureaucratic programs and government subsidies.