In 2018, US nuclear power plants achieved a record generation of 807.1TWh despite the closure of several plants since the previous peak of 807.0TWh in 2010.
The Energy Information Administration (EIA) attributed the increase to capacity additions from plant uprates, combined with shorter refuelling maintenance cycles. The US nuclear fleet in 2018 also saw its highest capacity factor on record at 92.6%.
Since 2010, the only new nuclear capacity in the USA is the Tennessee Valley Authority's 1.2GWe Watts Bar 2. However, there were 2.0GW of thermal uprates to US reactors between 2010 and 2018, which EIA said is "nearly the equivalent" of adding two new Watts Bar 2 reactors. A total of 98 reactors at 60 plants were in operation at the beginning of 2018, but seven plants with a combined capacity of 5.3GWe have retired since 2013.
Two plants - Pilgrim in Massachusetts and Three Mile Island - are expected to retire this year, and the closure of a total of twelve reactors by 2025 will see US nuclear capacity fall by 10.5GWe. Georgia Power's Vogtle 3 and 4, which are due to come online in 2021 and 2022, will not match this capacity.
Opportunities for further uprates are also "shrinking", the EIA said, with the US Nuclear Regulatory Commission anticipating only 60MW of thermal uprate applications up to 2020. According to the EIA's Annual Energy Outlook 2019 Reference case, net electricity generation from US NPPs is projected to fall by 17% by 2025 to be offset by output from new natural gas, wind and solar power plants.