First US test of modular reactor reaches criticality

In a significant advancement for nuclear energy, a startup named Antares has announced that its test reactor at the Idaho National Laboratory has achieved criticality. This milestone, which was celebrated on Thursday, marks the first time a new reactor design has reached this important threshold since the Trump Administration's executive order aimed at fast-tracking the development of nuclear power in the United States. The executive order, issued over a year ago, tasked the Department of Energy with ensuring that three distinct reactor designs would reach criticality within a year. While the modular reactor ecosystem has seen the emergence of various innovative designs, Antares stands out as the first to successfully reach this significant milestone. It's important to note that reaching criticality indicates that the nuclear reactions within the reactor have become self-sustaining, but it does not imply that the reactor is generating power at this stage. Antares’ reactor utilizes a new fuel system known as TRISO, which simplifies some of the complexities and safety concerns associated with traditional reactor designs by focusing on the fuel itself. The TRISO fuel consists of small pellets featuring a uranium oxide core, encased in multiple layers of carbon designed to regulate the energy released during fission reactions. Additionally, these pellets are protected by a robust ceramic shell that can endure the extreme temperatures generated by the contained uranium, showcasing a promising evolution in nuclear technology.