TVA's next-gen small nuclear reactor will open at Clinch River site in Oak Ridge

The Tennessee Valley Authority will introduce the next generation of nuclear power at its Clinch River site just miles from the cradle of some of America’s most important nuclear research.

TVA is not acting alone. As part of an agreement announced March 23, TVA will work in concert with GE Hitachi Nuclear Energy, Ontario Power Generation in Canada and Synthos Green Energy in Poland to finance and design a new small modular reactor.

Small modular reactors hold the promise of swifter and less expensive construction and safer operations, as well as a much less obtrusive footprint in the regions they serve.

If successful, this version of small nuclear reactors could be deployed in the U.S., Canada and Poland, lowering costs, mitigating risks and combining knowledge from each of the companies.

The investment – about $400 million jointly from the four organizations – could pay off in two ways: bolstering the diversity and reliability of the electric grid, and expanding the footprint of small modular reactors in the U.S. and abroad.

More on TVA and SMRs:How TVA plans to make East Tennessee a leader in the next generation of nuclear energy

What is a small modular reactor?

A small modular reactor is any nuclear reactor that generates about 300 megawatts or less of electricity, Greg Boerschig, vice president of TVA’s Clinch River Project, told Knox News in an exclusive interview Feb. 27. The major components of these reactors can be manufactured in factories and shipped to a site to be put together. This would cut down on time and money spent, two issues that previously weighed down construction of the currently operating nuclear reactors.

The goal of successful small nuclear reactors is to improve on the problems with current nuclear reactors. According to TVA, this includes:

• Being less expensive

• Taking up less room

• Taking less time to construct

• Improving safety measures

How could this agreement reduce risks?

Nuclear reactors can be expensive and take a long time to build. In the past, TVA has started projects for traditional nuclear plants – the huge complexes notable for their massive cooling towers – that have fallen through, leading to a loss of investment.

“The best experience you get is when things don't go the way you want them to,” TVA CEO Jeff Lyash told Knox News in an exclusive interview. “And when things don't go the way you want them to, the key is to learn from it and not repeat the same mistakes, not ‘Never do that again.’”

In order to mitigate the risk of this new venture into nuclear, the joint agreement between the four companies could allow them to reduce their individual costs while also using knowledge from one another.

For example, Ontario Power Generation is closer to deploying this small modular reactor design than TVA, and expects to complete construction at the end of 2028, according to the news release. Lyash said the Canadian company is running about 18 to 24 months ahead of TVA.

Due to the difference in timeline, TVA can learn from Ontario Power Generation’s process of constructing and deploying the small nuclear reactors.

Ontario Power Generation, meanwhile, can use TVA’s knowledge of operating light water reactors, including “three of the world’s largest boiling water reactors,” Lyash said.

More news in Oak Ridge:How could uranium have caught fire at Y-12?

TVA plans to test technology before deploying it

In addition to the agreement, TVA announced it will be testing steel bricks for the reactor building, Lyash said. While the technology has been used in other construction, it hasn’t been used in nuclear construction.

The bricks are manufactured and then assembled on site into modular units. Lyash said the bricks will be put into an excavation, assembled and then filled with concrete, “So you have a composite steel concrete building, but it’s modular in nature rather than traditional construction, which drove a huge amount of cost and schedule overrun at Vogtle." (That facility is a traditional nuclear reactor owned by Southern Company that was recently constructed in Georgia.)

The composite brick technology will be tested at the the Clinch River site, where a steel brick structure will be built to “perfect the technology, the process, the procedures, the workforce in advance and take all those lessons learned,” Lyash said.

The project will allow TVA to learn what it will be like to use this technology on its site before actually using it for the small modular reactor.

“It goes to your question, of why are you going to do better than Vogtle; that’s a great lesson learned where the first time they tried to build that shield building was on site at Vogtle with a workforce and a set of engineers and they struggled mightily with it,” Lyash said. “And so we’ve said ‘Fine, we’re not going to repeat that mistake.’”

Where is the money coming from?

The TVA Board approved up to $200 million for TVA's New Nuclear Program in 2022 and Lyash said the money for TVA’s portion of the $400 million will come from that budget.

What is the small modular reactor design?

The small modular reactor these three utilities will use is GE Hitachi’s BWRX-300, a generation three light water boiling water reactor, Boerschig told Knox News last month in an exclusive interview.

This type of reactor is similar to TVA’s Browns Ferry reactors, which are also light water boiling water reactors. The new technology for the small modular reactor design wouldn’t be too different from the older reactors, and there is an established supply chain and proven technology due to GE’s experience building these reactors.

Boerschig also said there would be reduced financial risk from cost overruns or delays. There is an established supply chain for the small modular reactor's fuel, which is the same as the fuel used at Browns Ferry.

During a visit to the Clinch River site by Tennessee Gov. Bill Lee and U.S. Rep. Chuck Fleischmann, R-Chattanooga, on March 3, Joe Shea, a TVA senior technical advisor for the project, said the site could house four small nuclear reactors. One small nuclear reactor is about the size of a football field.

The smaller size also means the emergency response zone for the site would be smaller than current nuclear power plants, which have emergency zones that span 10 miles around the plant. For the Clinch River site, the emergency response would go only as far as the site’s boundary.

More:TVA prepared in case of an emergency at Watts Bar Nuclear Plant; its neighbors should be, too

What is the timeline for building the new nuclear reactors?

All four companies will need to go through regulatory processes on their end to deploy GE Hitachi’s SMR at their locations.

Lyash said that there is a “gated” process for TVA to move forward in deploying the SMR.

“But the gates are not on ramps; they’re off ramps,” Lyash said. “Where you'd say, ‘Hey, it's not looking exactly like I thought, there's reason to pause, let's get off the highway and take a rest,’ or ‘There's some fatal flaw, let's get off this road altogether.’”

TVA is currently working on a construction permit application it will need to submit to the Nuclear Regulatory Commission, the federal agency in charge of civilian use of radioactive material. Once the application is ready, TVA will decide whether to proceed on its path to deploying the SMR at the Clinch River site. Lyash previously told Knox News he anticipates the decision will be made during the first half of 2024.

Additionally, TVA is looking at other sites to deploy SMRs, according to a TVA news release.

Anila Yoganathan is a Knox News investigative reporter. Email: anila.yoganathan@knoxnews.com. Twitter @AnilaYoganathan. Support strong local journalism by subscribing at knoxnews.com/subscribe. 

This article originally appeared on Knoxville News Sentinel: TVA's next-gen small nuclear reactor will be built near Oak Ridge