US nuclear generation down but share remains the same

Output from US nuclear power plants totalled 778 million MWh in 2021, 1.5% less than the previous year. Nuclear's share of US electricity generation across all sectors was 19%.

Since 2017, the EIA has included all US generating plant retirements since 2002 in its Preliminary Monthly Electric Generator Inventory. Six nuclear units with a total capacity of 4736 MWe have retired since the end of 2017, and three more, with a combined capacity of 3009 MWe, are scheduled to retire in the coming years. These are: Palisades, in Michigan, which is scheduled to retire later this year; and Diablo Canyon, in California, where one unit is scheduled to retire 2024 and one in 2025.

Only one of the five 2021 nuclear retirements that EIA expected, of January that year, actually took place. Exelon Generation reversed the decision to retire the Byron and Dresden plants - each home to two units - following the passage by Illinois of energy legislation supporting their continued operation.

The loss of electricity generation from the only retirement of the year - Entergy Corporation's Indian Point unit 3, which closed in April after nearly 60 years of nuclear power generation at the site in New York state - was partially offset by an increase in the generation of the remaining nuclear fleet at a higher capacity factor, EIA said. The US fleet achieved an average nuclear capacity factor 93% in 2021.

The Bipartisan Infrastructure Law, enacted in November 2021, includes the allocation of some USD6 billion to prevent the premature retirement of existing nuclear power plants.

Vogtle units 3 and 4 in Georgia remain the only nuclear units currently under construction in the USA. The two AP1000 units - each rated at 1114 MWe - are scheduled to come online by the end of 2023.