Abstract The total available cow dung is enough to feed only 20% of the Gobar gas plants required in rural India. Therefore a new, manually operated straw biogas plant has been successfully developed for those ruralities having insufficient cow dung to feed their small plants. The new family size unit operates on nonlignified mature or green vegetative waste (cut into small pieces) on a continuous fermentation basis. The rectangular masonry digester is provided with two stirrers and covered with a rectangular free-floating mild steel gas-holder. The stirrers are operated for a few minutes twice daily by one person. The slurry handling problems have been totally eliminated during routine operations. The new plant is comparable with the family size KVIC Gobar gas plant. Complete details for installation, operation, maintenance, and economics of the vegetative waste biogas plant have been described.