MIT Technology Review is reporting that four microreactors in the United States achieved criticality by the July 4 deadline set by the Trump administration. The goal was to see three new microreactors reach this technical milestone, which signifies a reactor's ability to sustain a chain reaction, by the nation’s 250th birthday. The publication noted that Antares Nuclear was the first to achieve criticality in June, followed by Valar Atomics, Deployable Energy and Aalo Atomics, with Aalo meeting the deadline in the early hours of July 4.
It said achieving criticality, specifically zero-power criticality, is a test of starting a nuclear chain reaction without producing meaningful power. This means the reactors are not yet ready to supply electricity to the grid. The companies are projecting aggressive timelines, with Aalo aiming to produce 10 megawatts of electricity by 2027 and Deployable Energy planning commercial reactors by 2028.
MIT Technology Review said significant technical challenges remain, such as adding cooling systems to transfer heat from the reactor core. It also highlighted potential regulatory hurdles with the Nuclear Regulatory Commission, despite a proposed new framework designed to speed up microreactor approvals. The publication also cited Third Way, a public policy think tank, which called the federal focus on the microreactor program an "unhelpful diversion" from increasing nuclear capacity, stating that "artificially accelerating project timelines is a short-term solution, not a long-term fix."
Full Article: Four nuclear reactors hit a big milestone in the US