Natural gas is the single-largest source of energy used to generate electricity in the United States, making up 43% of electricity generation in 2023. Natural gas-fired power plants accounted for the second-most U.S. generating capacity additions in 2023, trailing only solar. Combined with increasing domestic supply and relatively low natural gas prices, the versatility of natural gas-fired power plants to meet a wide range of requirements across many U.S. markets is one of the main reasons for their growth. However, the dispatchability, efficiency, and broad regional coverage of natural gas-fired power plants vary significantly. In addition, decades of advancements in natural gas turbine efficiency mean that the age of natural gas-fired plants affects how those plants are used.