Frequently Asked Questions

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

The average age of U.S. commercial reactors is about 36 years. The oldest operating reactors are Oyster Creek in New Jersey, and Nine Mile Point 1 in New York. Both reactors entered commercial service on December 1, 1969. The newest reactor to enter service is Tennessee’s Watts Bar Unit 2, which began operation in 2016. The next-youngest operating reactor is Watts Bar Unit 1, also in Tennessee, which entered service in 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:
Status of NRC reactor license renewal applications
Watts Bar Unit 2 Complete and Commercial

Last updated: March 3, 2017

Other FAQs about Nuclear

On This Page:


Conversion & Equivalents





General Energy

Natural Gas





Full list of upcoming reports

Sign up for email notifications

Get the What's New RSS feed

Didn't find the answer to your question? Ask an energy expert.