Nuclear power plants in the United States

Nuclear units in the 2025 EIA-860 data total 103.7 GW of nameplate capacity, 7.5% of the US fleet. It is the main source at 56 plants; Illinois has the most, with 12.4 GW. More of today’s nuclear capacity came online in 1986 than in any other year (9,991 MW). The oldest unit still working went into service in 1969 at Nine Mile Point Nuclear Station, New York.

When today’s nuclear capacity was built

Above the line: capacity still operable in 2025, by the year each unit came online. Below: nuclear capacity retired in each year, including plants that have closed completely (EIA’s retired-generator file).

States with the most nuclear capacity

Illinois12.4 GW
Pennsylvania10.5 GW
South Carolina6,875 MW
Georgia6,506 MW
Alabama5,630 MW
North Carolina5,395 MW
Texas5,139 MW
Tennessee4,981 MW
Michigan4,314 MW
Arizona4,210 MW
Florida3,914 MW
Virginia3,654 MW
New Jersey3,631 MW
New York3,398 MW
California2,323 MW

Largest units

The single biggest nuclear generator is unit 2 at Peach Bottom, rated at 1,499 MW.

Plant	State	Unit size	Online
Peach Bottom	Pennsylvania	1,499 MW	1974
Grand Gulf	Mississippi	1,440 MW	1985
Palo Verde	Arizona	1,403 MW	1986
Palo Verde	Arizona	1,403 MW	1986
Palo Verde	Arizona	1,403 MW	1988
Peach Bottom	Pennsylvania	1,377 MW	1974
South Texas Project	Texas	1,354 MW	1988
South Texas Project	Texas	1,354 MW	1989

The 25 largest nuclear plants

Rank	Plant	State	Runs on	Capacity	First unit	Operator
1	Vogtle	Georgia	Nuclear	4,658 MW	1987	Georgia Power Co
2	Palo Verde	Arizona	Nuclear	4,210 MW	1986	Arizona Public Service Co
3	Browns Ferry	Alabama	Nuclear	3,854 MW	1974	Tennessee Valley Authority
4	Turkey Point	Florida	Nuclear	2,978 MW	1972	Florida Power & Light Co
5	Peach Bottom	Pennsylvania	Nuclear	2,876 MW	1974	Constellation Nuclear
6	South Texas Project	Texas	Nuclear	2,709 MW	1988	STP Nuclear Operating Co
7	Oconee	South Carolina	Nuclear	2,667 MW	1973	Duke Energy Carolinas, LLC
8	Watts Bar Nuclear Plant	Tennessee	Nuclear	2,540 MW	1996	Tennessee Valley Authority
9	TalenEnergy Susquehanna	Pennsylvania	Nuclear	2,532 MW	1983	TalenEnergy Susquehanna LLC
10	Braidwood Generation Station	Illinois	Nuclear	2,450 MW	1988	Constellation Nuclear
11	Byron Generating Station	Illinois	Nuclear	2,450 MW	1985	Constellation Nuclear
12	Sequoyah	Tennessee	Nuclear	2,441 MW	1981	Tennessee Valley Authority
13	McGuire	North Carolina	Nuclear	2,441 MW	1981	Duke Energy Carolinas, LLC
14	Comanche Peak	Texas	Nuclear	2,430 MW	1990	Luminant Generation Company LLC
15	Catawba	South Carolina	Nuclear	2,410 MW	1985	Duke Energy Carolinas, LLC
16	PSEG Salem Generating Station	New Jersey	Nuclear	2,382 MW	1971	PSEG Nuclear LLC
17	LaSalle Generating Station	Illinois	Nuclear	2,340 MW	1984	Constellation Nuclear
18	Diablo Canyon	California	Nuclear	2,323 MW	1985	Pacific Gas & Electric Co.
19	Donald C Cook	Michigan	Nuclear	2,285 MW	1975	Indiana Michigan Power Co
20	Limerick	Pennsylvania	Nuclear	2,277 MW	1986	Constellation Nuclear
21	Millstone	Connecticut	Nuclear	2,260 MW	1975	Dominion Energy Nuclear Conn Inc
22	St Lucie	Florida	Nuclear	2,160 MW	1976	Florida Power & Light Co
23	Dresden Generating Station	Illinois	Nuclear	2,019 MW	1970	Constellation Nuclear
24	Quad Cities Generating Station	Illinois	Nuclear	2,019 MW	1972	Constellation Nuclear
25	Brunswick Nuclear	North Carolina	Nuclear	2,003 MW	1975	Duke Energy Progress (NC)

All 56 in the finder