Oklo completes modern U.S. nuclear reactor build in 229 days

Oklo, a microreactor developer, has completed construction of its Groves One pilot isotope-production reactor in 229 days. While not the fastest in history, CEO Jacob DeWitte noted it is the fastest U.S. non-military reactor build completed under modern Department of Energy (DOE) and environmental regulations.

The project was executed using private capital and commercial suppliers on private land, making it the first DOE Reactor Pilot Program reactor to achieve criticality outside of government-owned property. On August 5, the Groves Isotope Test Reactor achieved criticality, marking a self-sustaining nuclear chain reaction.

Oklo aims to use this project as a repeatable blueprint to meet rising energy demands from American manufacturing and the AI sector. The company plans to generate revenue from an Idaho radiochemistry lab in early 2027, with further commercial Aurora powerhouse projects and deployments at the Idaho National Laboratory targeted for 2027 and 2028.