Field experience with leaf litter-based biogas plants

Biogas plants answer a major search for clean cooking fuel in rural areas of the developing world where there is a dire need for replacing the existing fuel, wood. Biogas plants that use non-dung herbaceous biomass residues such as leaf litter and agro-residues have a large potential and promise for the future. These plants however need to operate on principles different from those of the slurry-based dung fermenters known in the past. In this article the dissemination experience of a brick masonry-based plug-flow-like biomass-based biogas plant is described. Field experience shows that biogas plants based on green/dried weeds can be constructed in rural India and made to produce biogas, which has the potential to alleviate the drudgery of cooking. The designs need to be made location-suitable. As fuel-wood is still available in most areas, to become successful new biogas plants need to use biomass feedstocks collected with less effort than that required to gather fuel-wood. Economic analysis suggests that there is potential to bring down costs to such low levels that they can become attractive in the future.