Facing energy crisis and climate change, the world is in need of a green, efficient, carbon-neutral energy source to replace
fossil fuels. Biogas, produced by biomethanation of organic materials, contributes to sustainable, reliable and renewable
energy. There is potential for biogas production from animal manure, energy crops and industrial wastes not only because
the wastes themselves can be treated to minimize the environmental impact, but also for biofuel methane, which holds
promise for the future. In the present study biomethanation of fresh water hyacinth, dry water hyacinth, poultry litter, cow
manure and primary sludge were studied in a series of laboratory experiments using 250 ml biodigesters with 7% total
solids and 60 days retention time. The digester fed with poultry litter produced highest biogas of 0.39 liters/g VS followed by
the digester fed with primary sludge (0.28 liters/g VS).
Key words: Biomethanation, biogas, water hyacinth, poultry litter, cow manure, primary sludge.