Southern Company, TerraPower, and Core Power (a U.K.-based firm focused on developing nuclear technologies for the maritime sector) have commenced pumped-salt operations in the Integrated Effects Test (IET) facility, the Atlanta, Ga.-based utility announced Tuesday, marking another milestone in the development of TerraPower’s first-of-a-kind, Generation IV Molten Chloride Fast Reactor (MCFR).

This year’s American Nuclear Society Annual Meeting was filled with great content, some of which was covered in the August issue of Nuclear News (beginning on p. 22). One of the meeting’s executive sessions, “Bringing Nuclear History Forward,” focused on advanced reactor (AR) history and was well attended. The United States—along with many countries around the world—is turning to nuclear to combat climate change. Part of this is funding new and innovative companies to create first-of-a-kind nuclear reactors to provide abundant and clean power. Looking at the current designs of interest to the community brings up interesting comparisons to the test and experimental reactors of the past. Test reactors like the Experimental Breeder Reactor-II (EBR-II), the Fast Flux Test Facility (FFTF), Peach Bottom, Fort St. Vrain, Germany’s AVR, and others now are more important than ever in providing insight, data, and operational lessons learned to develop the next generation of reactors.

Advanced nuclear technology firm TerraPower announced today the selection of four suppliers to support its Natrium reactor demonstration project, in development near a retiring coal plant in Kemmerer, Wyo.

The Department of Energy today released its final environmental assessment (EA) and a proposed finding of no significant impact (FONSI) for the design, construction, and operation of the Molten Chloride Reactor Experiment (MCRE) at Idaho National Laboratory. The draft EA was released earlier this year, in March, for four weeks of public comments.

Concept art of a tank type sodium-cooled fast reactor. (Image: MHI)

The Japanese government has chosen Mitsubishi Heavy Industries (MHI) to head up the conceptual design and research and development of a demonstration sodium-cooled fast reactor, the Tokyo-based engineering firm announced recently.

MHI is to oversee the work in partnership with Mitsubishi FBR Systems Inc. (MFBR), an MHI Group engineering company established in 2007 to develop and design fast breeder reactors.

Conceptual design work is scheduled to commence in fiscal year 2024, with operation of the unit slated for the 2040s.

Reactor roadmap: According to MHI’s announcement, in the strategic roadmap for fast-reactor development adopted by the Japanese Cabinet in December 2018, a policy was defined to assess the efficacy of several types of technologies to be developed following a competition among private-sector companies. The roadmap was subsequently revised by the Cabinet in December 2022, at which time two decisions were made: (1) to select a sodium-cooled fast reactor as the target of the conceptual design of the demonstration unit and (2) to select a manufacturer to serve as the core company in charge of the reactor’s design and requisite R&D.

Small modular reactor firm X-energy and Energy Northwest, owner and operator of the Columbia nuclear power plant in Richland, Wash., announced yesterday the signing of a joint development agreement (JDA) for up to 12 Xe-100 SMRs in central Washington, capable of generating up to a total of 960 MWe.

The JDA defines and details the scope, location, and schedule under which the commercial development of the project will move forward, the companies said, adding that they will also work together to determine the best approaches to licensing and regulatory matters, as well as the project delivery model. Currently, the Xe-100 project is expected to be developed at a site adjacent to the Columbia facility, with the first module coming on line by 2030.

TerraPower and Centrus Energy Corp. announced on July 17 that they have signed a memorandum of understanding to “significantly expand their collaboration aimed at establishing commercial-scale, domestic production capabilities for high-assay, low-enriched uranium (HALEU)” to supply fuel for TerraPower’s first Natrium reactor. Nearly three years ago, TerraPower first announced plans to work with Centrus to establish commercial-scale HALEU production facilities. The two companies signed a contract in 2021 for services to help expedite the commercialization of enrichment technology at Centrus’s Piketon, Ohio, facility.

NuScale Power and TerraPower both signed agreements earlier this week with South Korean entities to support development of the American firms’ respective reactor technologies.

Nuclear energy was the focus of a recent NPR 1A podcast episode, hosted by journalist Jenn White, who welcomed guests to discuss the role of nuclear energy in the future of the United States. The guests—Joe Dominguez, chief executive officer of Constellation Energy; Samantha Gross, director of the Energy Security and Climate Initiative at the Brookings Institution; and Edwin Lyman, director of Nuclear Power Safety for the Union of Concerned Scientists—participated in the episode, titled “Where Does Nuclear Energy Fit in a Carbon-Free Future?”

Portland, Ore.–based PacifiCorp—owner of the soon-to-be-retired Wyoming coal plant selected in 2021 as the future site of TerraPower’s Natrium reactor demonstration project—has released its 2023 Integrated Resource Plan, which recommends the addition of two more Natrium units to the company’s generation resource mix by 2033.

A tiny 200-kWt reactor the Department of Energy says would be the first critical fast-spectrum circulating fuel reactor and the first fast-spectrum molten salt reactor (MSR) could be built and operated inside the Zero Power Physics Reactor (ZPPR) cell at Idaho National Laboratory’s Materials and Fuels Center (MFC). Details included in the Molten Chloride Reactor Experiment (MCRE) draft environmental assessment (EA)—released on March 16 for two weeks of public comment (later extended to four weeks, through April 14)—covered the potential environmental impacts associated with the development, construction, operation, and decommissioning of MCRE at INL, facilitated by the National Reactor Innovation Center (NRIC).

The Department of Energy’s commitment to breaking down market barriers with initiatives, programs, and access to facilities is making it simpler and more efficient than ever for industry to partner with national laboratories. It is especially timely, as the country continues to face evolving security, economic, and clean energy challenges. Partnering opportunities via the DOE’s Cooperative Research and Development Agreements (CRADAs) and Strategic Partnership Projects (SPPs) are particularly prevalent in the commercial nuclear community and have seen a tremendous amount of funding and support dedicated to advancing the development, demonstration, and deployment of new reactor technologies.

TerraPower, the advanced nuclear company backed by Bill Gates, announced last week that the start date for its Natrium reactor has been pushed back. As Russia is currently the only commercial source of the high-assay low- enriched uranium (HALEU) the plant requires, the company faces a lack of fuel availability. TerraPower originally planned to use Russian fuel to get its demonstration reactor up and running by 2028, but Russia’s invasion of Ukraine has dashed those plans.

Advanced reactors and small modular reactors with strikingly different coolants and sizes offer an array of different benefits, but when it comes to fuel cycle issues, including spent fuel and waste, they have a lot in common with conventional light water reactors. Two reports released within the last week—a National Academies of Sciences, Engineering, and Medicine (NASEM) consensus committee report two years in the making and a Department of Energy study released by Argonne National Laboratory—address the timely topic of advanced reactor fuel cycle issues. While the NASEM committee ventured to define research and infrastructure needs to support the entire nuclear power fuel cycle, inclusive of new technologies, for decades to come, the DOE report compares the front- and back-end fuel cycle metrics of three reactor designs (from NuScale Power, TerraPower, and X-energy) that have been selected for DOE cost-share–funded demonstrations within this decade. Together, these reports provide assurance that the fuel cycle needs of a fleet of new reactors can be met and point to near-term research and planning needs.

Since at least June of last year—when TerraPower and PacifiCorp announced plans to site the Natrium reactor demonstration project at one of Wyoming’s retiring coal plants—the concept of repurposing those plants to host nuclear reactors has been a popular topic of conversation among the energy cognoscenti.

Nuclear technology firm TerraPower and utility partner PacifiCorp have launched a study to evaluate the feasibility of deploying up to five additional Natrium reactor and integrated energy storage systems in the utility’s service territory by 2035, the companies announced yesterday. (PacifiCorp’s business units—Pacific Power and Rocky Mountain Power—serve customers in California, Oregon, and Washington, and in Idaho, Utah, and Wyoming, respectively.)

Global Nuclear Fuel–Americas (GNF-A) and TerraPower announced their plans to build a Natrium fuel fabrication facility next to GNF-A’s existing fuel plant near Wilmington, N.C, on October 21. While more than 50 years of fuel fabrication at the site have supported the boiling water reactor designs of GE (GNF-A’s majority owner) and GE Hitachi Nuclear Energy (GEH), the Natrium Fuel Facility will produce metallic high-assay low-enriched uranium (HALEU) fuel for the sodium fast reactor—Natrium—that TerraPower is developing with GEH.

“The world's largest chloride salt system developed by the nuclear sector” is now ready for operation in TerraPower’s Everett, Wash., laboratories. Southern Company, which is working with TerraPower through its subsidiary Southern Company Services to develop molten chloride reactor technology, announced on October 18 that the Integrated Effects Test (IET) was complete. The multiloop, nonnuclear test infrastructure follows years of separate effects testing using isolated test loops, and it was built to support the operation of the Molten Chloride Reactor Experiment (MCRE) at Idaho National Laboratory that the companies expect will, in turn, support a demonstration-scale Molten Chloride Fast Reactor (MCFR).

The Department of Energy’s management of its commercial-scale reactor demonstration projects has “generally been consistent with requirements to address risk,” according to a Government Accountability Office (GAO) report published recently. The GAO found that the DOE has met existing project management requirements, and that the two offices managing the awards—the Office of Nuclear Energy (NE) and the Office of Clean Energy Demonstrations (OCED)—plan to introduce additional project management tools, such as external independent reviews. The GAO recommended that the DOE adopt those plans as institutional best practices for other large energy projects, and the DOE concurred.

U.S. nuclear technology company TerraPower announced yesterday the close of a $750 million equity raise—one of the largest advanced-nuclear investment drives to date, according to the announcement—with $250 million of that contributed by South Korean firms SK Inc. and SK Innovation.

Both firms are subsidiaries of the Seoul-based conglomerate SK Group, South Korea’s second-largest conglomerate, after Samsung Group.