US-based TerraPower and Centrus Energy Corp have signed a memorandum of understanding (MoU) to expand their collaboration aimed at establishing commercial-scale, US production capabilities for high-assay, low-enriched uranium (HALEU). The fuel is needed to supply TerraPower’s first-of-a-kind Natrium reactor and energy storage system.

TerraPower and GE Hitachi Nuclear Energy are developing Natrium technology, which features a sodium fast reactor combined with a molten salt energy storage system. The system features a 345 MWe reactor and can be optimised for specific markets. Its thermal storage has the potential to boost the system’s output to 500 MWe of power for more than five and a half hours when needed. This allows for a nuclear design that follows daily electric load changes and helps customers capitalise on peaking opportunities driven by renewable energy fluctuations. As more renewables are integrated into the grid, the demand for gigawatt-hour-scale energy storage will continue to increase.

In October 2022, Global Nuclear Fuel-Americas (GNF-A), a GE-led joint venture, and TerraPower agreed to build a Natrium Fuel Facility at the site of GNF-A’s existing plant site near Wilmington. The Natrium Fuel Facility will be jointly funded by TerraPower and DOE through the Advanced Reactor Demonstration Program, which aims to speed the demonstration of advanced reactors through cost-shared partnerships with US industry. The Natrium Fuel Facility will use HALEU. The US Energy Act of 2020 authorised DOE to support availability of HALEU for domestic commercial use.

Under the new MoU, Centrus and TerraPower will collaborate to ensure the Natrium demonstration reactor has access to HALEU at the milestones necessary to meet the project’s 2030 operation date. The two companies said they will establish a cost-competitive and timely source of enrichment capacity in the US at Centrus’s HALEU production facility. TerraPower and Centrus have been working together since 2021 when they entered into a contract for services to help expedite the commercialisation of domestic enrichment technology at Centrus’s Piketon, Ohio, facility.

“TerraPower is committed to a successful and timely delivery of the Natrium demonstration reactor,” said Chris Levesque, TerraPower president and CEO. “This expanded collaboration with Centrus represents TerraPower’s commitment to reinvigorating the domestic supply chain as we bring advanced reactors to market within the decade. Generation IV reactors are the solution we need for the energy grid of the future and this MoU will ensure we can fuel these reactors for decades to come.”

“Centrus is ready to pioneer US HALEU production and to meet the needs of TerraPower in bringing their advanced reactor to market,” said Centrus President & CEO Daniel B Poneman. “American HALEU production is vital for deploying US-designed advanced nuclear reactors. Establishing the domestic HALEU supply chain is critical for our energy independence.”

In February, Centrus completed the operational readiness review for its HALEU production facility and in June received permission from the Nuclear Regulatory Commission to begin operation. Under the MoU, Centrus will work toward scaling up production capacity with additional centrifuge cascades to meet TerraPower’s fuel requirements.

TerraPower plans a demonstration plant, planned for Kemmerer in Wyoming to validate the design, construction, and operational features of the Natrium technology. However, in December, TerraPower postponed the expected start date of its Kemmerer reactor by at least of two years. The company had originally hoped to commission the plant in 2028 using Russian-supplied HALEU. The conflict in Ukraine, however, made continuing Russian HALEU deliveries unlikely.

Image: Centrus Energy’s HALEU demonstration cascade (courtesy of Centrus Energy)