The United States has begun construction of its first Small Modular Reactor

The advanced nuclear technology company, Oklo Inc., has begun construction of the Aurora-INL reactor. This is a sodium-cooled fast reactor that uses metallic fuel and builds upon the design and operational legacy of the Experimental Breeder Reactor II (EBR-II), which operated from 1964 to 1994.

Oklo obtained the recovered EBR-II fuel through a competitive process managed by the U.S. Department of Energy (DOE) in 2019. In November 2025, the company announced that it had received approval for the Nuclear Safety Design Agreement (NSDA) to manufacture its initial core at the Aurora Fuel Fabrication Facility (A3F) located at Idaho National Laboratory (INL).

Kiewit Nuclear Solutions Co., one of North America’s largest construction and engineering firms, will serve as the lead constructor, collaborating on design, procurement, and construction under a Framework Agreement established in July 2025.

This project is one of three in which Oklo participates under the DOE’s Advanced Reactor Demonstration Program. The program was created in response to executive orders signed in May 2025 to accelerate the deployment of advanced nuclear technology and modernize the licensing process.

With this milestone, the United States joins the race for Small Modular Reactors (SMRs), marking a new era in nuclear technology.