EMERY COUNTY, Utah — Valar Atomics has brought its experimental small nuclear reactor online in the Utah desert as part of a U.S. Department of Energy program aimed at accelerating development of advanced reactor technology, marking a milestone for the company’s Ward 250 test system.
The reactor completed a zero-power fueled criticality demonstration at the Utah San Rafael Energy Lab in Emery County, the Department of Energy said on June 18. Criticality means the reactor achieved a sustained nuclear chain reaction under controlled test conditions, but the demonstration was not a commercial power operation.
The Ward 250 reactor is part of the DOE Reactor Pilot Program, which seeks to support the testing of advanced nuclear designs. Valar Atomics said its system is designed around a compact reactor concept using technologies including TRISO fuel, helium cooling and graphite moderation.
The Utah San Rafael Energy Lab said the facility is intended for research and development activities, including validating reactor components, training personnel and supporting future regulatory processes rather than immediate commercial electricity generation.
The project has received support from federal and state officials as part of broader efforts to expand advanced nuclear energy development in the United States. The DOE said Valar’s demonstration represented the first DOE-authorized reactor built outside a national laboratory to reach this testing milestone.
Valar Atomics’ reactor was transported to Utah earlier in 2026 in a joint federal effort involving the Department of Energy and the Department of Defense. The transfer was described by officials as a demonstration of the potential mobility of smaller nuclear systems designed for remote or specialized energy needs.
The company has said the Ward 250 design is intended for future applications including hydrogen production, industrial energy and other uses that require reliable power sources. Those applications remain dependent on further testing, regulatory approvals and future development steps.
Advanced small reactors and microreactors have drawn increased attention from policymakers and energy companies seeking alternatives for power generation, including for data centers and industrial facilities. The DOE has launched additional initiatives to provide testing locations and support for advanced reactor developers, reflecting renewed federal interest in nuclear deployment.
Valar’s Utah demonstration does not represent a commercial reactor deployment, and additional testing and regulatory work will be required before any broader use. The company and government partners have not announced commercial electricity production from the facility, with the project remaining focused on research and reactor validation.
