A total of 121 U.S. coal-fired power plants were repurposed to burn other types of fuels between 2011 and 2019, the Energy Information Administration reported.
Most of those plants, 103 of the 121, were converted to burn natural gas or replaced by a gas-fired plant.
At the end of 2010, there were 316.8 gigawatts (GW) of coal-fired capacity in the United States. By the end of 2019, 49.2 GW of that capacity was retired, 14.3 GW had boilers converted to burn natural gas, and 15.3 GW was replaced by a gas-fired combined cycle plant.
The decision for plants to switch from coal to natural gas was driven by stricter emission standards, low natural gas prices, and more efficient new natural gas turbine technology, according to the EIA.
The EIA expects more conversions to take place in the future, especially in the Midwest and Southeast, as the owners of coal-fired plants continue to manage the challenges posed by emission standards and low natural gas prices.
The federal agency says it has been notified of eight planned gas-fired combined-cycle projects, five of which are already under construction, that will replace existing coal plants.
Investor-owned Alabama Power had the most conversions between 2011 and 2019, switching 10 generators at four coal plants totaling 1.9 GW. Those conversions, which took place between 2015 and 2016, were mostly done to comply with the requirements of the Environmental Protection Agency’s Mercury and Air Toxics Standards (MATS) rules.
The EIA noted that there are generally two different methods used to switch coal-fired plants to natural gas. The first is to retire the coal-fired plant and replace it with a gas-fired combined-cycle plant. The second is to convert the boiler of a coal-fired steam plant to burn other types of fuel, such as natural gas.
Between 2011 and 2019, the EIA found that the owners of 17 coal-fired plants chose replacement, installing 15.3 GW of new gas-fired capacity, which was 94% more than the 7.9 GW capacity of the coal plants they replaced. The increase in capacity is largely a result of the advanced technology of the gas-fired combined-cycle plants installed, the EIA said.
In the same 2011-2019 time frame, the owners of 104 coal-fired plants converted those plants to burn other fuels. Eighty-six of those plants were converted to burn natural gas. Others were configured to burn petroleum coke, waste materials from paper and pulp production, or wood waste solids. A few of the plants maintained the ability to burn either coal or gas, depending on which is most economically efficient.
To see the full EIA report, click here.