Frequently Asked Questions

How much electricity does a nuclear power plant generate?

As of December 1, 2016, there were 99 operating nuclear reactors at 61 nuclear power plants in the United States. The R. E. Ginna Nuclear Power Plant in New York is the smallest nuclear plant in the United States, and it has one reactor with an electricity generating capacity1 at 508 megawatts (MW). The Palo Verde nuclear power plant in Arizona has three reactors and has the largest combined electricity generating capacity1 of about 3,937 MW.

The amount of electricity that a power plant generates depends on the amount of time it operates at a specific capacity. For example, if the R. E. Ginna  reactor operates at 508 MW capacity for 24 hours, it will generate 12,192 megawatthours (MWh). Most power plants do not operate a full capacity every hour of every day of the year.

1Net summer capacity.

Learn more:
How many nuclear power plants are in the United States, and where are they located?
What is the difference between electricity generation capacity and electricity generation?
Capacity factors for utility scale generators primarily using fossil fuels
Capacity factors for utility scale generators not primarily using fossil fuels
U.S. nuclear generation and generating capacity (historical monthly capacity and generation by state and reactor)
Nuclear energy (historical monthly and annual data on the total number of U.S nuclear reactors, electricity capacity and generation, and capacity factors)
U.S. Nuclear Industry
Nuclear Power Plants

Last updated:  December 7, 2016

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