Developers, officials talk advanced reactor outlook with NRC

The public had a rare opportunity Tuesday morning when the Nuclear Regulatory Commission gathered leaders from the Department of Energy, the Canadian Nuclear Safety Commission, TerraPower, Radiant, Westinghouse, and X-energy to share updates on their respective high-profile new nuclear projects and initiatives.

During the meeting, titled "Advanced Reactor Landscape: Current Status and Moving Forward," federal and industry officials presented on their respective endeavors, providing new updates, refreshers on previously announced information, and takeaways from their experiences.

DOE updates: As has been previously reported, three participants in the Reactor Pilot Program-Antares Nuclear, Valar Atomics, and Aalo Atomics-reached criticality on or before the July 4 target date set by Executive Order 14301, "Reforming Nuclear Reactor Testing at the DOE." One participant in the DOE's Nuclear Energy Launch Pad, Deployable Energy, also reached criticality by the Fourth of July.

Assistant Secretary for Nuclear Energy Theodore Garrish updated the public and the NRC on the foursome's post-criticality plans.

• Antares Nuclear: An electricity-producing prototype reactor, Mark-1, will undergo testing in 2027 to demonstrate the reactor's integrated performance. The company also plans to build out manufacturing space in California and testing facilities at Idaho National Laboratory in 2028.
• Valar Atomics: Additional higher-power demonstrations are expected in 2026 and 2027.
• Deployable Energy: Reactor physics testing that includes passive shutdown and decay heat testing are to take place in 2026. Full-power and transient testing is expected by July 4, 2027, with a maritime demonstration by July 4, 2028.
• Aalo Atomics: A full-power test is expected in 2027, followed by the company's first commercial, multireactor deployment in 2028. The company expects to build 1 GW or more of nuclear capacity by the end of 2030.

According to Garrish, three pilot participants have reached criticality; Last Energy, Oklo, and Radiant have had their preliminary documented safety analyses (PDSA) approved; and Atomic Alchemy (now Oklo Isotopes) has had its DSA approved.

CNSC update: International collaboration is part of the mindset at the Canadian Nuclear Safety Commission. For instance, a memorandum of cooperation between the CNSC, the NRC, and the U.K.'s Office for Nuclear Regulation (ONR) facilitates work on small modular reactors. This comes in the form of joint reviews, comparing their respective approaches to advanced reactor regulatory work, prelicensing activities, research, training, and workforce development.

Beth Vary, director general for the CNSC's Directorate of Advanced Reactor Technologies, said international collaboration is shaping the deployment of the BWRX-300 in the U.S. and Canada. In 2022, the CNSC and NRC formed a working group to assess the BWRX-300 design, developing multiple reports that facilitated the review of Ontario Power Generation's License to Construct application. The assessment lasted 26 months rather than the typical 32 months because of the collaboration, she said.

"Additional benefits include strengthening transparency, enhanced training opportunities, improved knowledge sharing, and identification and development of administrative tools for continued collaboration," Vary said. "Together these outcomes support timely, rigorous regulatory reviews and the effective delivery of our mandate."

TerraPower update: TerraPower intends to submit a Part 50 operating license application for its Kemmerer-1 power plant to the NRC by March 2028, according to its presentation on Tuesday. Ahead of this submittal, TerraPower submitted a regulatory engagement plan last October and an updated plan this past March.

TerraPower Senior Vice President of Regulatory Affairs George Wilson said preapplication work has played its part in the crafting of the operating license application. Preapplication meetings have already started, he said, and TerraPower is also weighing the pros and cons of using Part 53 and Part 57 rulemakings.

Preapplication engagement played a major role ahead of TerraPower submitting its construction permit application in 2024. Wilson said the company had more than 60 preapplication meetings with the NRC; took a preapplication readiness assessment; and developed 15 topical reports, three technical reports, and six white papers.

"These preapplication engagements that we had-including several training sessions with the NRC staff-the better the staff was prepared to do our review, the more they knew, the faster the reviews went," he said.

Radiant update: Radiant Chief Nuclear Officer Rita Baranwal listed a few past, present, and future milestones to support her argument that Radiant was "a company of firsts," including the following:

• Becoming the first to use INL's Demonstration of Microreactor Experiments (DOME) test bed.
• Performing a full-scale, full-power extended duration test, slated for later this year.
• Signing an agreement with the U.S. Air Force to deliver a commercial microreactor to Buckley Space Force Base in Colorado.
• Building fueling and manufacturing facilities at Oak Ridge, Tenn.

While Radiant's Kaleidos microreactor did not reach criticality on or before July 4, Baranwal said the company is following a detailed multistep deployment plan that will be completed at DOME this year.

"We have a five-phase plan," she said. "The first is to ship and fuel the reactor at DOME. The second is to achieve zero-power criticality. The third step is to operate at 1 MWt. The fourth step is to ramp up to full power and full temperature. And the fifth step-the most important in this deployment schedule-is to operate for 150 hours continuously without any operator intervention."

Westinghouse update: Westinghouse submitted Revision 20 of the AP1000 design certification document (DCD) to the NRC in the spring, which establishes Vogtle-4 as the standard AP1000 reference plant for U.S. deployment. Westinghouse believes this move will enable a fleet-scale deployment of their flagship advanced modular reactor in the United States, plans that also received a boost this summer with the DOE's announcement of $17.5 billion in conditional supply chain loans to help finance equipment procurements for AP1000 projects.

Nader Mamish, Westinghouse's vice president of global regulatory affairs, used his presentation to explain how Westinghouse's efforts to find licensing efficiencies will impact multiple areas. Incorporating lessons learned from Vogtle should enable future combined license reviews to focus more on site-specific and safety-significant considerations. Furthermore, an updated AP1000 design certification will not only help with domestic deployment, but will also help facilitate international deployment efforts.

X-energy update: X-energy has three advanced nuclear projects in the works in the United States:

• Its TRISO-X commercial advanced nuclear fuel fabrication facility in Tennessee, which would be the first of its kind in North America.
• The deployment of X-energy's Xe-100 at a Dow chemical facility in Texas.
• A 960-MWe deployment of its Xe-100 reactors at Energy Northwest's Cascade Advanced Energy Facility in Washington state, with Amazon pledging its support.

A separate international project involving X-energy and U.K. energy company Centrica would deploy a 6-GW fleet of Xe-100 SMRs across the U.K., the first of which would come to a site in Hartlepool, England. According to the X-energy presentation delivered by Vice President of Regulatory Affairs Jennifer Wheeler, the first electricity generation would be expected in the mid-2030s, pending regulatory approval.