U.S. Oklo's Isotope Test Reactor Approved for Unrestricted Operation

Recently, the Groves-1 isotope test reactor of U.S. company Oklo, located near Lockhart in Caldwell County, Texas, officially received approval from the U.S. Department of Energy (DOE) for unrestricted operation. Since the test reactor first achieved criticality in August of this year, less than a year has passed since groundbreaking, setting a new record for advanced nuclear reactor construction.

It is reported that Groves-1 is one of 11 advanced reactor pilot projects selected by the U.S. Department of Energy in August 2025. With the DOE formally lifting the final operating restrictions on the facility, the reactor has smoothly entered the research, testing, and training phase. Oklo CEO and co-founder Jacob DeWitte stated that the team will use this valuable platform to build a professional workforce and establish operating systems, accumulating key experience for the efficient delivery of future nuclear projects and the construction of the flagship-class "Aurora" fast neutron reactor.

The routine operation of the facility will directly serve multiple cutting-edge testing and personnel training missions. Groves-1 will not only serve as an important training and qualification platform for future nuclear power personnel, but will also continuously evaluate the performance and reliability of control rod drive mechanisms and conduct criticality and reactivity benchmark tests. These measured data will effectively support Oklo's isotope production capacity, engineering design models, and even provide data support for fuel performance and power uprates of future light water reactors and large light water reactors.

Under the U.S. Atomic Energy Act, the U.S. Department of Energy has the authority to authorize reactors for research, development, and demonstration. In response to the executive order issued in May 2025, the DOE has greatly streamlined the authorization pathway to accelerate the commercial deployment of advanced reactors. Meanwhile, the Nuclear Regulatory Commission (NRC) also recently finalized a new rule allowing applicants to directly use test data from DOE or Department of Defense reactor demonstration projects to support commercial license applications, thereby significantly improving the efficiency of independent safety reviews.