Biomass is material derived from recently living organisms, which includes plants, animals and their byproducts.  Manure, garden waste and crop residues are all sources of biomass. It is a renewable energy source based on the carbon cycle, unlike other natural resources such as petroleum, coal, and nuclear fuels.
Simple use of biomass fuel (Combustion of wood for heat). Animal waste is a persistent and unavoidable pollutant produced primarily by the animals housed in industrial-sized farms.
There are also agricultural products being grown for biofuel production. These include corn, switchgrass, and soybeans, primarily in the United States; rapeseed, wheat and sugar beet primarily in Europe; sugar cane in Brazil; palm oil and miscanthus in Southeast Asia; sorghum and cassava in China; and jatropha in India. Hemp has also been proven to work as a biofuel. Biodegradable outputs from industry, agriculture, forestry and households can be used for biofuel production, using e.g. anaerobic digestion to produce biogas, gasification to produce syngas or by direct combustion. Examples of biodegradable wastes include straw, timber, manure, rice husks, sewage, and food waste. The use of biomass fuels can therefore contribute to waste management as well as fuel security and help to prevent or slow down climate change, although alone they are not a comprehensive solution to these problems.
- AGORES – Biogas Biofuel Lille (PDF)
- AGORES – Biogas Biofuel Stockholm (PDF)
- University of Adelaide – An Introduction to Biogas
- Prometheus Energy Company
- Biogas in Rural Costa Rica
- Landfill Gas Generation
- Solid Waste Association of North America
- Landfill Gas Symposium
- Biogas in Spain
- Biogas in UK & Europe