U.S. power companies retired more than 546 coal-fired power units, between 2010 and the first quarter of 2019, and these units comprised nearly 102 gigawatts of generating capacity, according to the U.S. Energy Information Administration (EIA). By 2025, plant operators expect to retire another 17 gigawatts of coal-fired capacity.
Coal-fired plants have been operating under significant economic pressure, and many operators have retired the plants because of flat electricity demand growth and increased competition from natural gas and renewables, according to the EIA. Operators in 2018 retired more than 13 gigawatts of coal-fired generating capacity, and this is the second-highest number of U.S. coal retirements. The highest number was 15 gigawatts in 2015.
Coal-fired units that have been retired since 2015 are larger and younger. The average retired unit in 2018 had a capacity of 350 megawatts and an age of 46 years. Those retired before 2015 had an average capacity of 129 megawatts and an average age of 56 years.
When a coal-fired plant is retired, it goes through four main phases: retirement, decommissioning, remediation and redevelopment. Decommissioning includes removing equipment and demolishing buildings. Remediation includes site clean up to allow for a new use. Redevelopment includes repurposing the new site or repowering for another generation technology.
Repowering a plant with natural-gas fired technology, such as a combined-cycle natural gas turbine plant, requires less space than a coal-fired plant, which can cover hundreds of acres. Repowering a former coal-fired plant with natural gas-fired elements has been an option because much of the infrastructure is already on site, such as transmission lines, substations and water.