Deployable Energy's Unity microreactor achieves criticality at Idaho National Laboratory after ~150 days of construction

Deployable Energy/Unity Microreactor

Deployable Energy's 1 MWe water-moderated, helium-cooled Unity microreactor reached criticality at Idaho National Laboratory on June 30, 2026, approximately 150 days after construction began. The reactor achieved full nuclear operation in its closed Brayton cycle power conversion system. Unity was the third of four US microreactors to reach criticality by early July 2026.

• 1 MWe water-moderated, helium-cooled microreactor reached criticality June 30, 2026 at INL
• Achieved full nuclear operation and sustained fission chain reaction in 150 days from project launch
• Uses standard low-enriched uranium fuel and closed Brayton cycle for electricity generation
• Third of four US microreactors to reach criticality by early July 2026, part of DOE's Nuclear Energy Launch Pad initiative
• Next phase is power conversion testing and full-power operation and endurance validation