Energy Department announces advanced nuclear reactor achieves significant critical milestone.
The U.S. Department of Energy announced a significant advancement in nuclear technology with the recent achievement of “criticality” by a small nuclear reactor under development at the Idaho National Laboratory. This milestone, reached by Antares Nuclear Inc., indicates that the reactor can sustain a self-perpetuating chain reaction, paving the way for potential electricity generation within a few years.
Antares Nuclear has become the first private entity to successfully achieve criticality under a pilot program initiated by the Trump administration, designed to enhance nuclear energy production in the country. This collaboration, which includes the support of the U.S. Army and other contractors, demonstrates a comprehensive effort to invigorate the nuclear sector in the United States.
Energy Secretary Chris Wright expressed enthusiasm regarding this progress, suggesting that the success marked a pivotal moment in what he described as an “American nuclear renaissance.” He commented on the capabilities of U.S. innovators and their potential to drive the future of energy technology, reduce energy costs, and strengthen the nation’s energy independence.
The achievement of criticality is seen as a testament to the administration’s efforts to eliminate regulatory barriers that have historically hindered the development of nuclear technologies. These initiatives were formalized through executive orders signed by President Trump in May 2025, which enhanced the authority of the Department of Energy concerning advanced reactor designs and lessened some oversight roles of the Nuclear Regulatory Commission, a body that has traditionally governed the U.S. nuclear industry.
Although the path to commercial deployment remains lengthy for the Antares system, it is initially aimed at military applications. The company forecasts that electricity generation could begin as early as late 2027, with field deployment set for the end of 2028.
Skeptics of nuclear energy caution that while advancements in technology show promise, the long-standing safety concerns surrounding nuclear reactors persist. Critics question whether microreactors can deliver safe and economically viable power. Edwin Lyman from the Union of Concerned Scientists, for example, characterized the recent transport of a microreactor as largely symbolic, arguing that it does not adequately reflect the viability or safety of the technology being developed.
Despite the controversies and challenges, the Department of Energy is moving forward with plans to achieve the criticality milestone for at least three additional test reactors by July 4, in celebration of the nation’s upcoming 250th anniversary. Currently, the agency has identified 11 advanced reactor projects, including that of Antares, as part of a broader Push towards practical nuclear energy deployment.
