Three US Microreactors Reach Criticality in Historic First for American Nuclear Energy
By
Economy Desk
Summary
Three US nuclear startups — Antares Nuclear, Valar Atomics, and Deployable Energy — achieved criticality with their advanced microreactor designs within weeks of each other in mid-2025, marking the first time in over 40 years that the US has seen three unique reactor designs reach this milestone in a single month. Deployable Energy's Unity reactor reached criticality in just 150 days from construction start, a pace unthinkable during decades of nuclear stagnation. The achievement signals a potential renaissance in American nuclear energy, driven by compact, deployable microreactor technology.
Source
bskyThree US Microreactors Reach Criticality in Historic First for American Nuclear Energyeasternherald.comKey quotes
· 3 pulledWhen engineers at the National Reactor Innovation Center brought Deployable Energy's Unity reactor to self-sustaining criticality on July 1, the compact machine completed the journey in roughly 150 days from construction start.
It was a pace that would have seemed implausible to anyone familiar with the past four decades of American nuclear stagnation.
Unity was the third advanced microreactor to go critical in the United States within a single month.
You might also wanna read
Antares achieves first criticality of Mark-0 microreactor at Idaho National Laboratory under DOE program
Antares has achieved initial criticality of its Mark-0 microreactor at Idaho National Laboratory under the DOE Reactor Pilot Program, becomi
antaresindustries.com·4d agoStartup Targets Datacenters With 3D-Printed Nuclear Reactor Module
Nuclear Startup Aalo Atomics Achieves Criticality With Mini Reactor, Meeting Trump's July 4 Deadline
Nuclear startup Aalo Atomics has achieved criticality with its Aalo-X mini nuclear reactor at a site near Idaho National Laboratory, meeting
forbes.com·1d ago
Idaho National Lab celebrates first advanced nuclear reactor startup in over 40 years under Trump program
U.S. Energy Secretary Chris Wright visited Idaho National Laboratory to celebrate the startup of the first new-age nuclear reactor to go onl
idahostatesman.com·5d ago
Startup unveils 3D-printed nuclear reactor module to power AI data centers —touted as ‘the world’s first subcritical, solid-state, factory-built thorium nuclear reactor’
Comments
Sign in to join the conversation.
No comments yet. Be the first.