Scientists Achieve Major Milestone in Molten Salt Nuclear Fuel Production

Researchers at the Idaho National Laboratory (INL) have made a significant advancement in nuclear energy by successfully producing enriched fuel salt for the Molten Chloride Reactor Experiment (MCRE). This experiment marks the first full-scale test of a molten chloride salt fast reactor, a groundbreaking step in the field of nuclear technology.

Bill Phillips, technical lead for salt synthesis, stated, “This is the first time in history that chloride-based molten salt fuel has been produced for a fast reactor.” He emphasized that this achievement signifies a major milestone for American innovation and reflects the nation’s commitment to advancing nuclear energy.

Collaboration and Future Prospects

The MCRE project is a public-private partnership involving Southern Company, TerraPower, CORE POWER, and the U.S. Department of Energy (DOE). This collaboration aims to demonstrate innovative nuclear technologies, with potential applications in the maritime sector. The MCRE will be the first reactor experiment hosted at the Laboratory for Operation and Testing in the United States (LOTUS), a facility being developed by the DOE’s National Reactor Innovation Center at INL. Operations are projected to commence by 2030.

Molten salt reactors differ fundamentally from traditional reactors, which typically utilize solid fuel rods and water for cooling. Instead, molten salt reactors employ a liquid fuel composed of a mixture of salts containing fissile material. This design offers several advantages, including higher operating temperatures, improved fuel efficiency, and enhanced safety. Additionally, it paves the way for new applications, such as compact nuclear systems suitable for ships and remote installations.

Jeff Latkowski, senior vice president of TerraPower and program director for the MCRE, remarked, “The Molten Chloride Fast Reactor represents a paradigm shift in the nuclear fuel cycle.” He noted that the successful synthesis of this unique fuel illustrates the collaborative progress being made in Generation IV nuclear technology.

Implications for Maritime Industry and National Goals

The potential benefits for the maritime industry are substantial. Don Wood, senior technical advisor for the MCRE, explained, “Molten salt reactors could provide ships with highly efficient, low-maintenance nuclear power, reducing emissions and enabling long-range, uninterrupted travel.” He believes this technology could catalyze the emergence of a new, mobile, and scalable nuclear sector.

Mikal Boe, CEO of CORE POWER, highlighted the importance of private sector investment in this venture. He stated, “With substantial private sector investments, including from the maritime industry, and with continued funding support from the DOE, this milestone accelerates completion of the MCRE.” Boe expressed confidence that this breakthrough will help revitalize the U.S. merchant shipping fleet and enable it to compete effectively with China.

The fuel salt production process commenced in 2020, with INL scientists aiming to convert 90% of uranium metal into uranium chloride and produce 18 kilograms of fuel salt per batch. Initial attempts yielded only 80% conversion, but in 2024, the team achieved a major breakthrough, reaching 95% conversion and full-batch production. They have demonstrated the ability to produce a batch in as little as one day. The first batch of fuel salt was delivered at the end of September 2023, with plans to produce four additional batches by March 2026.

The work aligns with national objectives to advance nuclear energy, as outlined in a 2025 executive order by former President Donald J. Trump. Jacob Yingling, a research scientist for fuel salt synthesis, noted the promise of molten chloride reactors, stating, “They offer the best blend of fuel efficiency, safety, and long-term sustainability.”

National policy is increasingly supportive of nuclear power advancements. Jess Gehin, INL’s Associate Laboratory Director for Nuclear Science & Technology, pointed out that recent executive orders have significantly impacted the nuclear energy sector, enabling acceleration in technology development.

As the MCRE progresses, its implications extend beyond fuel production. James King, MCRE project director, asserted, “This milestone isn’t just about producing fuel—it’s about proving that the U.S. can lead in next-generation nuclear innovation.” He emphasized that the MCRE is laying the groundwork for a more secure energy future, marking just the beginning of what is possible in advanced nuclear energy.