IEA, Difference in the levelised cost of electricity between natural gas (CCGT) versus coal plants (supercritical) in the United States, 2013-2017, IEA, Paris https://www.iea.org/data-and-statistics/charts/difference-in-the-levelised-cost-of-electricity-between-natural-gas-ccgt-versus-coal-plants-supercritical-in-the-united-states-2013-2017, Licence: CC BY 4.0