Deployable Energy’s Unity project has become the third advanced reactor to reach zero-power criticality by July 4.
Houston, Texas-based Deployable Energy, founded in 2025, achieved this milestone under the DOE’s Nuclear Energy Launch Pad Initiative, which is the successor to DOE’s reactor pilot program. The Launch Pad, established in March, is based at the National Reactor Innovation Center at DOE’s Idaho National Laboratory (INL).
Last year, DOE, under Executive Order 14301, established a reactor pilot program with the goal of having at least three test reactors reach zero-power criticality by July 4 this year. Deployable Energy applied to be in DOE’s reactor pilot program last year, but was not selected.
The company’s test microreactor, named Unity, joins Antares Nuclear’s sodium-heat-pipe-cooled, tri-structural isotropic – or TRISO-fueled reactor and Valar Atomics’ high-temperature gas-cooled reactor. Both of these test reactors went critical under DOE’s reactor pilot program.
Deployable Energy is developing a one-megawatt water moderated, gas-cooled deployable nuclear microreactor. The company said this technology could be used for remote communities, emergency response operations, defense missions and industrial needs.
Criticality is the point where a nuclear reactor holds a controlled, self-supporting chain reaction. Deployable Energy reached the threshold days after DOE approved its documented safety analysis on June 18. Its preliminary design safety analysis was approved by DOE on May 22.
Deployable Energy said in a Wednesday press release that the company reached this milestone in “record time”, with “roughly 150 days since project kick-off with INL” to reach criticality.
“Having instrumental partners in the Department of Energy, INL, and our suppliers has been crucial to the success of this criticality test,” said Bobby Gallagher, Co-Founder and CEO at Deployable Energy. “This accomplishment demonstrates the dedication of our team and partners and moves us collectively one step closer to delivering reliable, resilient, and deployable nuclear energy solutions by leveraging the expertise and capabilities at INL and the existing fuel supply chain.”
Secretary of Energy Chris Wright called Deployable Energy’s achieving criticality a “significant milestone on a timeline many thought was unachievable.”
“Last week, I had the opportunity to see the Unity demonstration reactor firsthand and meet with the talented teams from Deployable Energy,” Wright said.
INL and DOE “made this historic moment possible on the eve of our nation’s 250th anniversary,” Wright continued, “Advanced nuclear technologies like Unity will help power the next generation of American industry, strengthen our energy security, and ensure the United States remains the world’s nuclear innovation leader.”
With the criticality of the Unity test reactor achieved, Deployable Energy said the reactor will enter a phased testing program. This will include further validation of its reactor physics, safety and full-power operations.
“These tests will provide additional data to verify reactor performance and support future licensing and commercialization efforts,” Deployable Energy said.
Though Deployable Energy became the third non-light water reactor to reach this milestone, Aalo Atomics could become the fourth test reactor to do so before the July 4 deadline. Last week, Wright said that he signed off on the company’s authorization permitting the reactor to go online.
Austin, Texas-based Aalo is developing its test reactor Aalo-X, a sodium-cooled extra modular reactor that will use low-enriched uranium dioxide fuel.