New Era for U.S. Nuclear Power: A First in 40 Years
After over four decades, the United States has unveiled a privately designed nuclear reactor, marking a significant milestone in its energy landscape.
On June 4th, the Antares Nuclear Mark-0 reactor achieved criticality at the Department of Energy’s Idaho National Laboratory. This novel reactor, developed by Valar Atomics, is unique as it generates heat from a nuclear core housed within a tent-like structure in the Utah desert. The Department of Energy heralded this event as the “rebirth of America’s nuclear power industry.”
“For far too long, nuclear power in America has been characterized by empty promises and delays,” an official remarked, adding that this achievement signifies a step towards fulfilling those commitments.
Former President Trump has expressed skepticism about large conventional reactors, considering them “too big, too complicated, and too expensive.” However, he is optimistic about the potential of small modular reactors. He has made a commitment to streamline the approval process for new nuclear reactors to “overcome bureaucracy.”
In May 2025, he signed several executive orders aiming for at least three small reactors to be operational by July 4, 2026, coinciding with the nation’s 250th birthday.
The Department of Energy kicked off a reactor pilot program that fast-tracked the approval of 11 new reactor designs, bypassing the lengthy traditional process of the Nuclear Regulatory Commission—previously a process that took over 20,000 hours. With this shift, the Department of Energy has taken a more hands-on role in oversight.
Jordan Bramble, CEO of Antares, commented on the pace of progress: “We promised criticality by 2026, power generation by 2027, and operational capabilities for our fighter jets by 2028. Today marks the first of these commitments on schedule.”
Nick Toolan, chief nuclear officer at Ocean Atomics, emphasized that these new reactors differ significantly from traditional mega-plants, which have an average age of 44 years. The latest designs, such as Radiant, utilize small fuel balls likened to gobstoppers; they are mass-produced for deployment in various settings, from military bases to disaster zones. To meet the timeline set by Trump, the third reactor must also reach criticality by July 4.
This month, the Trump administration announced plans for $17.5 billion in financing to construct ten large-scale conventional nuclear power plants, leveraging Westinghouse technology, with a construction start date targeted for 2030.
John Wagner, Director of Idaho National Laboratory, clarified the broader goal: “The objective goes beyond just achieving criticality; we’re aiming for 400 gigawatts of nuclear capacity by 2050.”
However, not all voices are in agreement. Edwin Lyman from the Union of Concerned Scientists has criticized the push as a “public relations stunt” and cautioned that relaxing regulations could undermine decades of safety advancements, arguing, “This takes us back to the 1950s, and that’s not progress.”
The fast-tracked program skipped the usual public comment period and environmental review often required by the DOE, with officials stating that such measures were unnecessary.
