The Department of Energy plans to award one or more contracts to deconvert high-assay low-enriched uranium (HALEU) from its post-enrichment gaseous uranium hexafluoride (UF₆) state to other chemical forms, such as metal or oxide. The DOE’s final request for proposals (RFP) for deconversion services was issued November 28 as one part of the agency’s effort—under the HALEU Availability Program—to establish a reliable domestic supply of advanced reactor fuel. The DOE will store the deconverted material until it is required by a fuel fabricator or other end user.

Researchers at Idaho National Laboratory in early 2023 manufactured commercial-grade high-assay low-enriched uranium (HALEU) fuel pellets to the specifications of a General Electric accident tolerant fuel design, INL announced November 21. A team working at INL’s Experimental Fuels Facility at the Material and Fuels Complex fabricated about two dozen uranium dioxide pellets using HALEU enriched up to 15 percent U-235.

In October, staff at Kairos Power’s testing and manufacturing facility in Albuquerque, N. M., began transferring 14 tons of molten fluoride salt coolant into an Engineering Test Unit (ETU)—the largest transfer of FLiBe (a mixture of lithium fluoride and beryllium fluoride) since the Molten Salt Reactor Experiment in 1969.

Richard A. Meserve

Climate change presents a grave threat, demanding increasing reliance on low-carbon energy over the coming decades. Nuclear power today contributes half of U.S. low-carbon generation, and achievement of climate goals requires the continued operation of existing plants. But there are competitors for low-carbon energy, and nuclear’s further role remains uncertain. The National Academies of Sciences, Engineering, and Medicine (NASEM) conducted a study to explore the challenges that must be overcome for widespread new nuclear deployment.¹ This article provides my summary of the study, highlighting and abbreviating some of its principal recommendations. Note that the italicized portions of the article are shortened versions of the recommendations in the report.

The Nuclear Regulatory Commission’s Office of Nuclear Regulatory Research is hosting two workshops on reactor topics before the end of the year.

The Nuclear Energy Agency has announced a new collaboration with the Electric Power Research Institute on an upcoming project that will focus on waste management strategies for small modular reactors and advanced nuclear energy systems.

Just a few hours after a new Speaker of the House of Representatives was elected on October 25, the White House sent a list of funding priorities for “critical domestic needs” to Congress for consideration as legislators restart the stalled annual appropriations process. Those priorities include $2.2 billion for low-enriched uranium (LEU) and high-assay low-enriched uranium (HALEU) enrichment capabilities. And to ensure that investment in domestic HALEU enrichment pays off, the White House is also calling for a long-term ban on enriched uranium from Russia.

The Department of Energy’s National Reactor Innovation Center (NRIC) awarded $3.9 million to three advanced nuclear energy developers on October 23 to design experiments to test microreactor designs in the Demonstration of Microreactor Experiments (DOME) test bed at Idaho National Laboratory.

The Nuclear Regulatory Commission is requesting comments on the regulatory basis for a proposed rule for light water reactor fuel designs featuring high-assay low-enriched uranium (HALEU), including accident tolerant fuel (ATF) designs, and on draft guidance for the environmental evaluation of ATFs containing uranium enriched up to 8 percent U-235. Some of the HALEU feedstock for those LWR fuels and for advanced reactor fuels could be produced within the first Category II fuel facility licensed by the NRC—Centrus Energy’s American Centrifuge Plant in Piketon, Ohio. On September 21, the NRC approved the start of enrichment operations in the plant’s modest 16-machine HALEU demonstration cascade.

American Nuclear Society Executive Director/CEO Craig Piercy visited One White Flint North, where he sat down with U.S. Nuclear Regulatory Commission chair Christopher Hanson for a one-on-one interview on September 18, 2023. The interview is available exclusively to ANS members to watch this week before it is released to the public. ANS members won’t want to miss the hour-long discussion, where Hanson opens up about important topics facing the NRC and the nuclear community and what he sees as the big successes during his first term as chair.

Oklo Inc. and Centrus Energy announced a new memorandum of understanding on August 28 to support the deployment of Oklo’s microreactor design, dubbed Aurora, near the Piketon, Ohio, site where Centrus plans to operate a high-assay, low-enriched uranium (HALEU) enrichment demonstration under contract to the Department of Energy by the end of the year.

It’s been almost 35 years since Illinois last added a nuclear power reactor to the grid (Braidwood-2, a pressurized water reactor operated by Constellation, reached commercial operation in October 1988). And it’s been 63 years since a research reactor reached initial criticality at the University of Illinois–Urbana-Champaign (UIUC). The university’s TRIGA Mark II started up in August 1960 and was shut down in 1998. For about 25 years, UIUC—the flagship public university in a state that generates more power from nuclear energy than any other—has lacked an operating research reactor.

Advanced reactors are promising energy systems that can enable the world to transition to a more sustainable energy matrix. These concepts are potentially more fuel efficient and safer, compared with previous generations of nuclear reactors. Many designs, like high-­temperature gas reactors (HTGRs) and molten salt fast reactors (MSFRs), target high outlet temperatures, allowing for their operation in processes where high heating is required, such as for hydrogen production and desalination.

Nuclear thermal hydraulics—for light water reactors or advanced reactors cooled by gas, metal, or salt—is all about defining safety and performance margins as things heat up.

Five pronuclear organizations—the Breakthrough Institute, Clean Air Task Force, ClearPath, Nuclear Innovation Alliance, and Third Way—have together penned a letter to the Nuclear Regulatory Commission, calling on the agency to take action on its emergency preparedness for advanced reactors rule—which, despite the explosion of interest in these technologies over the past few years, has yet to be finalized.

A large, bipartisan group of Capitol Hill lawmakers last Friday wrote a letter to the members of the Nuclear Regulatory Commission urging them “to carefully review and modify as necessary” the 10 CFR Part 53 draft licensing framework for advanced nuclear reactor technologies.

Take note! Registration closes today for the U.S. Department of Energy Conference for Newcomers: Understanding Exports of Advanced Reactor Technologies, scheduled for July 26–27 at Argonne National Laboratory in Lemont, Ill.

Contact Mercedes Trent (mercedes.trent@nnsa.doe.gov) to sign up for the conference. Additional information will follow upon registration.

Advanced reactors may be key to a clean energy future, but to prove it they’re going to need fuel—and that fuel will be derived from limited uranium resources and managed throughout the nuclear fuel cycle, whether that cycle is open (like the current fuel cycle) or closed (with reprocessing). Six panelists convened on June 12 during the Annual Meeting of the American Nuclear Society for the executive session “Merits and Viability of Advanced Nuclear Fuel Cycles: A Discussion with the National Academies.” They discussed those fuel cycles and the findings of a National Academies of Science, Engineering, and Medicine (NASEM) consensus committee released as a draft report in November 2022 and published earlier this year.

At the 2023 ANS Annual Meeting, Steven Arndt (as of the close of the meeting, ANS immediate past president) led a president’s session on the mission of the Nuclear Regulatory Commission—a not particularly surprising topic, given that he spent over 30 years at the agency in various roles.

Sola Talabi

Advanced reactor risk management creates awareness, assessment, and action on issues of uncertainty to ensure safe, cost-effective, and on-schedule deployment of advanced reactors. It requires people, processes, and tools to identify and assess risks both qualitatively and quantitatively.

For safety risk, this requires characterizing how advanced reactor features such as natural convective cooling may reduce or retire risks. It also includes identifying and assessing new risks that may be introduced by advanced reactor features. Retired and reduced safety risks include certain loss-of-coolant accidents because the pumps and piping systems associated with these accident scenarios are eliminated. New safety risks that may be introduced include resuspension of fission products due to the higher containment aspect ratios that some advanced reactors have. New transportation risks may arise in the case of irradiated microreactors after service. Hence, advanced reactor risk assessments should include a mechanistic assessment of the net effect of the retired and new risks to quantitatively characterize overall plant safety. This may be achieved with probabilistic risk assessment procedures and tools.