Coal is primarily used as fuel to generate electric power in the United States. In coal-fired power plants, bituminous coal, subbituminous coal, or lignite is burned. The heat produced by the combustion of the coal is used to convert water into high-pressure steam, which drives a turbine, which produces electricity. In 2019, about 23 percent of all electricity in the United States was generated by coal-fired power plants, according to the U.S. Energy Information Administration.
Certain types of bituminous coal can also be used in making steel. Coal used for steel making needs to be high in carbon content and low in moisture, ash, sulfur, and phosphorous content. Coal that meets these specifications is known as metallurgical coal. Coal also has a myriad of other uses, including in cement production, carbon fibers and foams, medicines, tars, synthetic petroleum-based fuels, and home and commercial heating.