Ameren Missouri’s 40-year operating license of the center was set to expire in 2024.

The license was renewed following a six-year review of the design and inspections.

Ameren Missouri design engineering director Sarah Kovaleski said: "The NRC’s review process for our license renewal application has been extremely thorough and provides verification that Callaway has the proper programs and plans to operate for 20 additional years."

The Callaway Energy Center is capable of generating electricity enough to power 780,000 average households annually.