WASHINGTON — The U.S. Department of Energy (DOE) is celebrating more historic milestones in America’s nuclear renaissance.
(DOE, June 18, 2026) — DOE Reactor Pilot Program participant Valar Atomics’ advanced reactor design, Ward 250, successfully completed a zero-power fueled criticality demonstration. The experiment took place at the Utah San Rafael Energy Lab in Emery County, Utah, and marks the first DOE-authorized reactor built outside of a national laboratory.
“Today marks another historic moment for America’s nuclear renaissance,” said U.S. Energy Secretary Chris Wright. “From the first-ever airlift of a small reactor aboard a U.S. military C-17 to successful zero-power criticality testing, Valar Atomics is delivering achievements that mark a revolutionary moment for advanced nuclear in this country. The Trump administration is proud to support the rebirth of America’s nuclear industry, ensuring Americans have access to affordable, reliable and secure energy for generations to come.”
Ward 250 is the second of multiple advanced reactors anticipated to go critical by the July 4th deadline set by President Trump in his May 2025 executive order. Criticality demonstrates that Ward 250 can sustain a controlled nuclear chain reaction, which must be achieved before the reactor can generate power. Earlier this month, Antares Nuclear’s Mark-0 reactor achieved criticality at Idaho National Laboratory.
“Nine months ago, this was an empty site. Today, there’s a critical reactor on it, built and operated by the Valar team,” said Isaiah Taylor, Founder & CEO of Valar Atomics. “We met the milestone the executive order set. This reactor was built to make power, and that’s exactly where we’re headed. I’m grateful to the Department of Energy, the State of Utah, the local community, and the many people who got us here.”
The Department’s Reactor Pilot Program has catalyzed rapid innovation and progress in furthering American advanced reactor designs. The Reactor Pilot Program leverages DOE authorization to expeditiously certify and construct first-of-a-kind advanced reactor designs for demonstration. Building on the Reactor Pilot Program’s success, DOE recently established the Nuclear Energy Launch Pad to further accelerate the deployment of advanced nuclear technologies.
Learn more about the Reactor Pilot Program.
(DOE / July 1, 2026) Meanwhile, the DOE also announced that its Nuclear Energy Launch Pad initiative, Deployable Energy’s demonstration reactor, Unity, successfully completed a zero-power fueled criticality demonstration at Idaho National Laboratory. Unity, which achieved criticality on June 30th, is the third DOE-authorized advanced reactor to go critical by the July 4th deadline set by President Trump in his May 2025 executive order. This criticality marks DOE’s fulfillment of a precedent-setting directive to reignite nuclear energy innovation in the United States.
With Antares Nuclear’s Mark-0 and Valar Atomics’ Ward 250 Antares reactors achieving criticality under DOE’s Reactor Pilot Program, the United States is the first country in history to achieve criticality in three unique advanced microreactor designs in a single month.
“Last week, I had the opportunity to see the Unity demonstration reactor firsthand and meet with the talented teams from Deployable Energy, INL and DOE whose work made this historic moment possible on the eve of our nation’s 250th anniversary,” Secretary of Energy Chris Wright said. “America’s nuclear renaissance is underway because of President Trump’s bold vision and ambitious goals. Yesterday, we accomplished a significant milestone on a timeline many thought was unachievable. 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.”
Deployable Energy completed the Unity criticality experiment under the Nuclear Energy Launch Pad initiative, managed by the National Reactor Innovation Center at Idaho National Laboratory. The next evolution of the Reactor Pilot Program, Nuclear Energy Launch Pad, leverages DOE authorization to expeditiously certify and construct first-of-a-kind advanced nuclear technologies for demonstration.
“We are proud to be a part of this historic achievement and I want to express Deployable Energy’s gratitude to the administration for setting an audacious goal to have three reactors reach criticality before July 4th, the U.S. Department of Energy for ensuring our ability to meet this goal with safety, quality, and speed, and the Idaho National Laboratory for providing an incredible partnership in execution. I also want to thank my team and supply chain partners of dedicated professionals. We would not have been able to meet this moment without their brilliance, boldness, and grit,” said Bobby Gallagher, Co-Founder and CEO at Deployable Energy.
As the first Nuclear Energy Launch Pad project to achieve the criticality milestone, Unity demonstrates how leveraging the national laboratory’s resources can expedite critical experiments and reactor demonstrations.
Learn more about the Nuclear Energy Launch Pad.
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