US-based Kairos Power has broken ground on a Salt Production Facility to be constructed at the company’s Manufacturing Development Campus at Mesa del Sol in Albuquerque, New Mexico. The facility will produce high-purity, molten salt coolant for Kairos Power advanced reactors, starting with the Hermes Low-Power Demonstration Reactor in Oak Ridge, Tennessee.

The coolant is a chemically stable mixture of lithium fluoride and beryllium fluoride salts known as “Flibe”. The Salt Production Facility will build upon lessons learned from the company’s Molten Salt Purification Plant in Ohio, which produced 14 tonnes of unenriched Flibe for the non-nuclear Engineering Test Unit (ETU 1.0) demonstration in Albuquerque last year.

ETU 1.0 is now undergoing decommissioning. It was the first of three systems that are being built to inform the design, construction, and operation of the Hermes low-power reactor that the company is using to advance the development of its fluoride salt-cooled high-temperature reactor (KP-FHR) technology.

Kairos Power is following a “rapid iterative development” approach to bring its KP-FHR advanced nuclear reactor to market. This means designing, building, and testing multiple prototypes, learning lessons, and improving processes along the way. ETU 1.0 was a full-scale, electrically heated prototype of Hermes. The next iteration, ETU 2.0, is already underway in Albuquerque and will focus on demonstrating the modular design of the reactor. After that, ETU 3.0 will be built in Oak Ridge, Tennessee adjacent to the eventual site of the Hermes reactor.

The new Salt Production Facility will employ a proprietary chemical process to produce large quantities of high-purity Flibe enriched in Lithium-7 that will meet the stringent specifications to be used inside a reactor.

The Salt Production Facility represents a major investment in Kairos Power’s vertical integration strategy. It will enable future process optimisation and establish the competency to scale up reactor-grade Flibe production for the commercial fleet. Kairos said it expects to create 20-30 full-time, high-paying jobs to support the construction and operation of the Salt Production Facility. The project’s general contractor is TIC-The Industrial Company, a subsidiary of Kiewit Corporation.

The project will also use funding from the US Department of Energy’s (DOE’s) Advanced Reactor Demonstration Program (ARDP) to supplement Kairos Power’s substantial private investment. In February, Kairos signed a technology investment agreement with DOE to put into effect the ADRP risk reduction award, the company received in 2020. DOE will provide up to $303m on a performance-based, fixed-price milestone basis to enable the design, construction, and commissioning of the company’s Hermes demonstration reactor. A construction permit for the reactor was issued by the. Nuclear Regulatory Commission (NRC) in December 2023.

A rendering of the Salt Production Facility at Kairos Power’s manufacturing development campus (Credit: Kairos Power)

The Hermes design is for a 35 MWt non-power version of the company’s fluoride salt-cooled high temperature reactor, the KP-HFR. Kairos has also submitted a construction permit application for Hermes 2, a proposed two-unit demonstration plant that would build on the experience of Hermes and would produce electricity and demonstrate the complete architecture of future commercial plants. Kairos says the Hermes demonstration reactors will help to mitigate technology, licensing, supply chain, and construction risk to achieve cost certainty for KP-HFR technology. Kairos is targeting commercial deployments in the early 2030s. Hermes is to be built at Oak Ridge.

The same day Kairos broke ground on the Salt Production Facility, the company held a dedication ceremony for the new Manufacturing Development Campus where it is piloting key manufacturing capabilities. The campus already hosts facilities for advanced reactor component manufacturing, U-stamped pressure vessel production, modular reactor construction, fuel fabrication process development, and large-scale, non-nuclear testing, welding, cutting, machining and, graphite pebble production with more planned.

Kairos is headquartered in Alameda, California and initially expanded to Albuquerque’s Mesa del Sol community in 2019, opening its facility in 2020 to establish a research and development engineering centre for the commercialisation of its advanced reactor technology. Kairos acquired the former Schott solar panel factory and 32 acres of land in the Mesa del Sol development to accommodate its future expansion. In four years, the company has made over $125m in capital investments at the site and more than doubled its initial hiring commitment with a current headcount of 130+ full-time employees. Kairos also has facilities in Oak Ridge (Tennessee) and Charlotte (North Carolina).

Kairos Power Chief Technology Officer and Co-founder Ed Blandford noted: “With the addition of molten salt coolant production, Kairos Power’s Manufacturing Development Campus will soon have all the capabilities we need to deliver the Hermes demonstration reactor and establish a credible path to scale up production for the commercial fleet.”

Alan Kruizenga, Vice President, Salt, said: “This Salt Production Facility is not only a first for Kairos Power, but for the US nuclear industry. This innovative facility establishes domestic production capacity for critical materials that will reduce our dependence on foreign suppliers. Building a domestic supply chain for Flibe is a significant hurdle to clear, but we believe it’s achievable.”

Acting Deputy Assistant Secretary of Nuclear Reactors Brian Smith said Kairos Power continues to make impressive strides towards demonstrating the Hermes reactor. “DOE is pleased with the company’s progress on its Advanced Reactor Demonstration Program Risk Reduction project, and we look forward to seeing what Kairos accomplishes next.”

Researched and written by Judith Perera