Seeking to expedite construction of advanced nuclear power facilities, the U.S. Nuclear Regulatory Commission has created a new licensing framework for microreactors that are 100 MWe or smaller, eyeing them as fast-deploying energy sources for AI data centers and other users that can be mocular, factory built and deployed without grid dependence.
Published May 1 in the Federal Register with a 42-day comment period, the proposed Part 57 rule outlines a “streamlined, risk-informed and flexible licensing pathway” that NRC claims could save up to $11.8 billion and shorten construction permit and operating license timelines to one year or less. The rule is the latest to emerge from the agency’s overhaul of regulations, prompted by the Biden-era ADVANCE Act to boost U.S. nuclear energy and by more recent presidential executive orders. It is also the latest framework developed for advanced reactor designs that represent a shift from light water technology.
«We are developing new licensing frameworks that are designed for safety, scale and speed,” NRC Chairman Ho K. Nieh said. U.S. microreactor startups have gained more than $1.2 billion in private capital, with a $6.8-billion global market expected by 2030, said one market report.
The proposed rule focuses on approval of fleets of identical reactors, use of alternative design standards, streamlined environmental reviews of projects with “limited impacts” and pathways for limited construction ahead of Commission permitting. It sets criteria based on a “consequence limit” and a “fuel mass limit,” allowing a design that meets those thresholds to use the framework.
“It’s not for us to choose which technology society … deploys,” Nieh said. “But if there’s a need for it …and a design that’s viable for licensing, we are going to have a framework ready to produce a safety decision.”
The commission’s newly created Office of Advanced Reactors will license and oversee new and advanced reactors, and lead the team issuing permits and licenses for new facilities and doing construction inspection.
The U.S. Energy Dept. said last month that three of four firms selected for its new federal Nuclear Energy Launch Pad program are developing microreactors. It allows them to begin discussions with the commission on “enhanced technical, regulatory and deployment support.”
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These include California-based Radiant Industries Inc., which is developing the Kaleidos microreactor that is designed to deliver reliable power in mission-critical environments, the firm says. It will test the 1-MW reactor this year at the DOE Idaho National Laboratory site and start deployment in 2028. The firm, which says it has raised more than $500 million in private funding to date, is building «the world’s first» factory to mass produce portable nuclear reactors in Oak Ridge,Tenn., representing an estimated $280-million investment.The facility’s Nuclear Regulatory Commission review is set for completion in December, Radian says.
The department will provide no funding to Launch Pad participants, but there are other options for design and construction support, according to the program website.
The Union of Concerned Scientists contends that the rule, among others, risks loosening proven nuclear power safety mandates. At a House Energy subcommittee hearing April 22, commissioners were queried on radiation safety measures, as well as on agency transparency and workforce supply. “Any potential nuclear renaissance will be cut short if the NRC can’t guarantee its independence,” said ranking member Rep. Frank Pallone (D-N.J.).
Also of concern—to both lawmakers and even commissioners—was the 8% reduction in the agency’s $892.3 million budget request for fiscal 2027 compared to what is enacted for fiscal 2026, including 2,606 full-time employee equivalents, a decrease of 7% from the current fiscal year
“The agency is being directed to do more with less despite a growing workload and aggressive new timeframes for agency licensing and oversight activities,» said Commissioner Bradley Crowell. «This is an unsustainable dynamic.»
