Oklo’s Groves Isotope Test Reactor has successfully achieved criticality under the U.S. Department of Energy’s (DOE) Reactor Pilot Program, marking another milestone for advanced nuclear technology in the United States.
The achievement was announced after testing at Oklo’s facility in Lockhart, Texas. It makes the Groves Isotope Test Reactor the fifth DOE-authorised advanced reactor to reach criticality this summer, highlighting the accelerating pace of next-generation reactor development.
The successful demonstration will provide operational data to support the design of a future commercial reactor capable of producing critical isotopes for healthcare, advanced manufacturing, scientific research, space missions and national security applications.
Commenting on the landmark achievement, Jacob DeWitte, Oklo co-founder and CEO, said: “Reaching criticality in less than a year is an incredible milestone for our team.
“Oklo developed Groves from a greenfield site on private land, completed full-scale civil excavation and construction, manufactured or commercially procured all components, including fuel, and developed its operating programs in-house.
“Taken together, we believe these accomplishments establish a new benchmark for the Reactor Pilot Program and set the stage for the future of advanced nuclear deployment at scale.”
Supporting the next generation of isotope production
The test reactor is intended to validate technologies that will underpin a commercial-scale isotope production system.
Medical isotopes play a vital role in cancer diagnosis and treatment, while other specialised isotopes are increasingly important for industrial processes, scientific research and emerging space technologies.
By achieving criticality, Oklo has taken an important step towards demonstrating that advanced reactor technologies can be developed more rapidly through alternative regulatory pathways while maintaining federal oversight.
DOE pilot programme accelerates advanced reactor deployment
Oklo joins Antares Nuclear, Valar Atomics, Deployable Energy and Aalo Atomics as companies that have progressed from reactor design to operational demonstration through the DOE Reactor Pilot Program.
The initiative provides technical support and authorisation for first-of-a-kind advanced reactor projects, enabling developers to test innovative reactor concepts more quickly than has traditionally been possible.
According to the DOE, the new authorisation pathway is intended to demonstrate how regulatory reform can accelerate advanced nuclear innovation while supporting the wider deployment of next-generation reactors across the United States.
With five advanced reactors reaching criticality this summer, the programme is being positioned as a key driver of renewed momentum in the US nuclear sector and future commercial deployment of advanced reactor technologies.
