Retirements of U.S. electric generating capacity to slow in 2024

Operators plan to retire 5.2 gigawatts (GW) of U.S. electric generating capacity in 2024, a 62% decrease from last year when 13.5 GW was retired and the least in any year since 2008, according to our latest Preliminary Monthly Electric Generator Inventory. Coal and natural gas jointly account for 91% of the planned capacity retirements in the United States this year.

Coal. After 22.3 GW of U.S. coal-fired electric generating capacity retired over the past two years, coal retirements will slow down in 2024. The 2.3 GW of coal-fired capacity scheduled to retire accounts for 1.3% of the U.S. coal fleet that was in operation as of the end of 2023. Coal retirements are scheduled to increase again in 2025 when operators expect to retire 10.9 GW. In 2024, coal retirements will come primarily from older units: the capacity-weighted average age of these retiring units is almost 54 years, about 10 years older than the weighted average age of operating coal units. U.S. coal units are retiring as the nation’s coal fleet ages and as coal-fired generators face competition from natural gas and, increasingly, renewables. The largest coal retirements in 2024 will be Seminole Electric Cooperative’s Unit 1 (626.0 megawatts [MW]) in Florida and Homer City Generating Station’s Unit 1 (626.1 MW) in Pennsylvania. The other two coal-fired units at the Homer City Generating Station retired last year.

Natural gas. The 2.4 GW of scheduled retirements of natural gas capacity represent 46% of expected U.S. capacity retirements in 2024 and 0.5% of currently operating U.S. natural gas-fired capacity.

Mystic Generating Station, a six-unit, 1,413-MW combined-cycle facility in Massachusetts, will account for 60% of the natural gas-fired capacity retirements in 2024. One of the nation’s oldest power plants, Mystic Generating Station has been providing power in the Boston area since the 1940s. The other five petroleum- and natural gas-fired units at Mystic have already retired, so with these last unit retirements the entire plant is scheduled to shut down when its cost of service agreement expires in May. The other 32% of the retiring natural gas-fired capacity will come from 16 simple-cycle combustion turbines totaling 754.0 MW at the Tennessee Valley Authority’s (TVA) Johnsonville station.

Petroleum. More than 450 MW of U.S. petroleum-fired capacity is scheduled to retire in 2024. Almost all of the retiring petroleum capacity will be from the TVA’s Allen power plant. The plant is shutting down its combustion turbine site consisting of 20 old combustion turbine units totaling 427 MW. These units supplied power during times of peak demand across the TVA power system. Allen was primarily a coal-fired plant before TVA retired all coal-fired units in 2018, replacing the capacity with the Allen Combined Cycle Natural Gas Plant, which went into operation in May 2018.