Despite the scheduled closure of more than 2,000 megawatts (MW) of nuclear generating capacity by 2019, scheduled additions of more than 5,000 MW of capacity between 2016 and 2020 could result in a net increase in total U.S. nuclear capacity.
Entergy Corp. announced in October its intention to close by mid-2019 the 685 MW Pilgrim Nuclear Power Stationlocated in Massachusetts. The closure of Pilgrim could take place even earlier, as Entergy could choose to shut Pilgrim down during the plant's scheduled refueling and maintenance in 2017. In addition to the just-announced plan to close Pilgrim, the 678 MW Oyster Creek Nuclear Generating Station in New Jersey is also scheduled to shut down in 2019.
There are currently five new reactors under construction in the United States. Watts Bar Unit 2 (estimated 1,150 MW capacity) in southeastern Tennessee, which recently received its operating license from the Nuclear Regulatory Commission, is projected to begin commercial operation in 2016. The Vogtle plant in eastern Georgia and the V.C. Summer plant in South Carolina, which have both experienced significant project delays of two to three years, are each currently scheduled to begin operating two new reactors (each with 1,117 MW capacity) in 2019 and 2020.
Thirty U.S. states have nuclear power plants; most are located east of the Mississippi River. Illinois has the most nuclear capacity of any state, followed by Pennsylvania. Exelon, the utility with the highest amount of nuclear power capacity in its generation assets, operates 17 reactors at 10 plants located in Illinois, Pennsylvania, and New Jersey.
Nuclear reactors are typically larger than natural gas- and coal-fired units—the average nuclear unit capacity is just under 1,000 MW, compared to about 130 MW for natural gas combined-cycle units and 270 MW for coal units. The nation's largest nuclear plant and second-largest power plant of any fuel type is the Palo Verde Nuclear Generating Station in Arizona, which has three reactors with a total capacity of 3,937 MW. The smallest operational nuclear plant is Fort Calhoun Nuclear Generating Station in Nebraska, with a capacity of 479 MW.
Including last year's closure of the 604 MW Vermont Yankee Nuclear Power Plant, four nuclear power plants (five reactors) have been shut down over the past four years, reducing nuclear capacity by more than 6,000 MW and leaving the United States with 99 operating nuclear power reactors at 62 different nuclear power plants.