Operators and owners of plants that burn gas (mostly methane, CH4) to produce electricity and usable heat. The gas is captured at landfills, swamps, digesters and coal mines. Methane is released during anaerobic digestion of manure, municipal solid waste (MSW) and other biodegradable matter. Also released is (often) carbon dioxide and other gases which should be separated from methane before burning. If the plant produces the gas mainly as (vehicle) fuel for others to consume it will be found in "Biogas Producers" within the "Biofuel" group.
