Biogas is the product of anaerobic digestion (decomposition without oxygen) of organic matter. It is mostly made up of methane and carbon dioxide, as opposed to natural gas, which is composed of nearly all methane and other hydrocarbons. When its composition is upgraded to a higher standard of purity, it can be called renewable natural gas and used as an alternative fuel in the same forms as conventionally-derived natural gas: compressed natural gas (CNG) and liquefied natural gas (LNG).

Biogas Links
Department of Energy’s Alternative Fuels Data Center – Learn the basic about biogas.
Pennsylvania State University’s Biogas Information Page – Information on anaerobic digestion and biogas safety.
Biogas Consultants, Equipment Dealers & Funders – Get in contact with biogas experts and funders