The Nuclear Regulatory Commission (NRC) issues licenses for commercial power reactors to operate for up to 40 years. These licenses can be renewed for an additional 20 years at a time.

As of June 15, 2023, 87 of the 92 commercially operating nuclear reactors in the U.S. have had their licenses extended to 60 years. Furthermore, owners can apply for subsequent license renewal (SLR), which would authorize units to operate for another 20 years. Among owners interested in this option is the Tennessee Valley Authority (TVA), which has said it plans to submit SLR applications for its Browns Ferry reactors by December 2023.

Manu Sivaraman, site vice president for the Browns Ferry Nuclear Plant, talked about the SLR process as a guest on The POWER Podcast. “There’s a lot of analysis that you do when you’re going to submit for a license renewal, especially a second license renewal,” he said. “So, number one is we benchmarked other sites that have done a 60 to 80 license application, because it’s not like this has been done hundreds of times. There’ve been a few sites that have done it, some similar to ours—a boiling water—so we took all those lessons learned and then built the project plan around: ‘How did everybody else do it?’ ”

While a great deal of analysis is required to complete the SLR process, Sivaraman said even more work must be done to ensure the plant can operate reliably for another 20 years. “It’s a living process,” Sivaraman explained. “We’ve got close to 100 major capital projects laid out for the next 20 years. And when we say major, we’re not talking go replace a small pump, we’re talking change the turbine rotor out—all the blades, the rotor, generator change outs, cooling tower replacements for long-term operation.” He suggested having TVA’s backing and commitment to extending the lives of the units, allows planning for prolonged operation and not simply trying to manage stop-gap projects from year to year.

“There’s also a whole host of modernization things we’re going to do—main control room modernization, digitalization of different systems, rad monitor change outs,” Sivaraman said, noting that many companies and industry groups, including the Electric Power Research Institute (EPRI), are regularly developing improvements to nuclear plant systems that enhance operations and safety.

Meanwhile, having a long-term plan is also good for employee morale and helps in attracting new workers, because people can have confidence in the plant being a steady source of employment for many years to come. “It’s a great opportunity to retain people because they know they’ve got a place to work and what they do matters,” said Sivaraman.

Notably, 80 years may not be the end of the line for nuclear plants. “It’s very preliminary, but there are conversations occurring in different pockets like EPRI—even the NRC—that I think have to do with ‘Okay, what does a 100-year extension look like?’ ” said Sivaraman. “It’s at its infancy, probably, right? But the fact that that discussion is happening, we can’t focus on just trying to get to 80, we need to think as though it can go past that.”

Sivaraman suggested the long-term planning process is the key to success. “It is not a once and done thing. It’s a living process that needs to have intelligence built into it as you go,” he said.