Definition: Coal

From Open Energy Information

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Coal

A combustible black or brownish-black sedimentary rock composed mostly of carbon and hydrocarbons. It is formed from plant remains that have been compacted, hardened, chemically altered, and metamorphosed by heat and pressure over geologic time (typically millions of years). It is the most abundant fossil fuel produced in the United States.[1][2]

Wikipedia Definition



Related Terms
Fossil fuelsBituminous coalAnthracite coalelectricity generationheatfuel cell
References
  1. http://205.254.135.24/tools/glossary/index.cfm?id=coal
  2. http://www.eia.gov/kids/energy.cfm?page=coal_home-basics