Santa Clara’s Oklo gets federal clearance to run its Texas test reactor without limits, moving from proving it works to research and training
The small reactor will train operators, test parts and gather data for Oklo’s planned power plants and a facility to make a cancer-treatment isotope.
Oklo, a Santa Clara company developing small nuclear power plants, said Nov. 11 that the U.S. Department of Energy has cleared its Groves-1 test reactor in Lockhart, Texas, for unrestricted operations. That lets Oklo move the reactor from a one-time demonstration into regular use for research, equipment testing and training of nuclear workers, according to the company’s announcement.
Groves-1, short for Groves Isotope Test Reactor, reached first criticality in August 2026, Oklo said. Criticality means a reactor is sustaining a steady nuclear chain reaction on its own. Oklo said it got there at low power less than a year after breaking ground, and that it was the first reactor in the Energy Department’s Reactor Pilot Program to do so on private land. That program lets companies build and run test reactors under Energy Department authorization rather than the usual, slower license from the Nuclear Regulatory Commission.
What the reactor will be used for
- Training and qualifying operators who will run Oklo’s future reactors.
- Testing equipment, including the control rod drives, the motors that move rods in and out of the core to speed up or slow down the reaction.
- Improving the control room. Oklo said operators wore eye-tracking glasses during a recent startup to record where they looked, to guide design changes.
- Measuring how the reactor’s chain reaction responds to changes, data Oklo says could help its own designs and possibly the large water-cooled reactors that make most U.S. nuclear power.
The work also feeds Groves-2 Forge, a planned Oklo pilot plant to make and process medical isotopes, radioactive forms of elements used in medicine. Its first focus is lutetium-177, which is used in targeted cancer treatments, the company said.
Why it matters
Oklo’s main goal is the Aurora powerhouse, a small “fast” reactor, one that uses faster-moving neutrons than today’s reactors and can run on recycled fuel. No Aurora plant is operating yet. Groves-1 is a low-power test reactor, not a power plant, and it does not send electricity to the grid. Oklo says lessons from running it will help it build more reactors faster. “Taking Groves-1 from greenfield to criticality in less than a year was an important demonstration,” said Jacob DeWitte, Oklo’s CEO and co-founder. Oklo is listed in its federal securities filings as based in Santa Clara.