Nuclear Energy Generation by State

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According to the most recent monthly data available from the U.S. Energy Information Administration (EIA), nuclear power generated 71,172 thousand megawatt-hours in July 2026. Nuclear energy accounted for 15.7% of U.S. utility-scale electricity generation that month.

Choose Energy’s October 2026 Nuclear Energy Generation Report compares nuclear electricity generation by state using July 2026 EIA data. The tables below show state rankings, monthly and annual changes, and nuclear power’s share of each state’s utility-scale electricity generation.

Illinois generated more nuclear electricity than any other state in July 2026, producing 8,610 thousand MWh. Pennsylvania ranked second with 6,678 thousand MWh, followed by South Carolina with 4,939 thousand MWh. Together, the top 10 states accounted for 63.8% of U.S. nuclear generation that month.

Illinois has more operating commercial nuclear power plant sites than any other state. The U.S. Nuclear Regulatory Commission (NRC) lists six operating sites with 11 reactors: Braidwood, Byron, Clinton, Dresden, La Salle County and Quad Cities. Pennsylvania and South Carolina each have four operating nuclear plant sites, with eight reactors in Pennsylvania and seven in South Carolina.

As of March 2026, the United States had 94 operating commercial reactors at 54 nuclear power plants across 28 states, according to the EIA. Plant and reactor totals differ because one nuclear power plant may contain multiple reactors. The NRC provides a complete list of operating nuclear reactors and their locations.

U.S. nuclear electricity generation increased 3.5% from June to July 2026, reaching 71,172 thousand MWh. Connecticut recorded the largest percentage increase, rising from 1,259 to 1,550 thousand MWh, while Minnesota recorded the largest decrease at 5.6%.

Generation figures are shown in thousand megawatt-hours (thousand MWh). States with no reported utility-scale nuclear generation in July 2026 are excluded from the nuclear generation rankings and comparisons: Alaska, Colorado, Delaware, Hawaii, Idaho, Indiana, Iowa, Kentucky, Maine, Massachusetts, Montana, Nevada, New Mexico, North Dakota, Oklahoma, Oregon, Rhode Island, South Dakota, Utah, Vermont, West Virginia and Wyoming.

U.S. nuclear electricity generation increased 0.6% year over year, rising from 70,781 thousand MWh in July 2025 to 71,172 thousand MWh in July 2026. Missouri recorded the largest percentage increase, rising 34.5% from 661 to 889 thousand MWh. Michigan recorded the largest decrease, falling 12.4% from 2,425 to 2,125 thousand MWh.

Annual changes compare July 2025 with July 2026. All 28 states with reported nuclear generation in July 2026 had comparable generation data for July 2025.

Nuclear power accounted for 15.7% of U.S. utility-scale electricity generation in July 2026. New Hampshire had the highest statewide nuclear share at 50.1%, followed by South Carolina at 47.6% and Illinois at 45%. These percentages compare nuclear generation with total utility-scale electricity generation in each state.

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