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Frequently Asked Questions

How old are U.S. nuclear power plants, and when was the newest one built?

As of June 2019, the average age of operating U.S. commercial reactors is about 39 years. The oldest operating reactor is Nine Mile Point 1 in New York, which entered commercial service in December 1969. The newest reactor to enter service is Tennessee’s Watts Bar Unit 2, which began operation in June 2016. The next-youngest operating reactor is Watts Bar Unit 1, also in Tennessee, which entered service in May 1996.

The U.S. Nuclear Regulatory Commission (NRC) licenses U.S. commercial nuclear reactors for 40 years. Prior to termination of the original license, companies may apply to the NRC for 20-year license extensions.

Learn more:
Does EIA have data on each power plant in the United States?
Nuclear power plant data
Watts Bar Unit 2 Complete and Commercial
Status of NRC reactor license renewal applications

Last updated: July 10, 2010


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