The first power plants ran solely on water or coal following the discovery of the fundamental principles of electricity generation by English scientist Michael Faraday in the early 1800s. Today, power plants rely on a variety of traditional energy sources such as coal, natural gas, nuclear, hydroelectric, wind generators, and petroleum, with supplementary amounts from solar energy, tidal power, and geothermal sources. In 2019, U.S. electricity generation from natural gas climbed to about 1.58 trillion kilowatt hours, while consumption of coal energy for electricity generation fell to about 539.42 million short tons in that same year. The net generation of U.S. nuclear power plants stood at around 809 terawatt hours of electricity in 2019.
The 2019 numbers for geothermal electricity generation amounted to approximately 16 billion kilowatt hours. In that same year, U.S. electricity net generation from hydropower, solar and wind sources amounted to nearly 650 billion kilowatt hours of electricity. Emissions from pollutants and greenhouse gases from fossil fuel-based electricity generation account for a significant portion of the world’s greenhouse gas emissions and U.S. electricity generation continues to contribute large shares of global totals.
Nevertheless, U.S. renewable electricity capacity continues to experience steady growth, accounting for some 20.5 percent of the total U.S. electricity generating capacity in 2018.