A U.S. Energy Information Administration chart ranks the 10 U.S. power plants that generated the most electricity in 2019. Nine of them were nuclear plants, and the tenth was the West County Energy Center, a natural gas plant in Florida. Together the 10 generated 230 million megawatthours, which was 5.6 percent of all U.S. electricity generation that year.

Palo Verde in Arizona ranked first at nearly 32 million megawatthours. Browns Ferry in Alabama followed, then Peach Bottom in Pennsylvania, South Texas Project in Texas and Oconee in South Carolina. Susquehanna in Pennsylvania, Braidwood and Byron in Illinois, and Vogtle in Georgia completed the list.

The mix changed over the decade. In 2010 the top 10 combined nuclear and coal plants. Coal's share of U.S. electricity generation fell from 45 percent in 2010 to 23 percent in 2019. Palo Verde, Browns Ferry and Oconee have stayed among the top 10 consistently because they are the only nuclear plants with three reactor units. Comanche Peak in Texas was in the 2010 top 10 but dropped out in 2019 because scheduled refueling and maintenance reduced its availability.

Capacity ranged from 2,300 megawatts at Byron to 3,937 megawatts at Palo Verde. Grand Coulee, the Washington hydroelectric facility with 6,809 megawatts of capacity, generated 16.6 million megawatthours in 2019, below every plant in the top 10.

Nuclear plants posted the highest capacity factor of any U.S. energy source, at 94 percent fleet-wide in 2019. The nine nuclear plants in the top 10 ranged from 89 percent at Browns Ferry to 99 percent at Byron and Peach Bottom. Natural gas combined-cycle units ranked second at 57 percent.

Source: U.S. Energy Information Administration - https://www.eia.gov/todayinenergy/detail.php?id=45276