Radiant Industriesa young Californian company specializing in nuclear innovation, recently passed a crucial test for its microreactor prototype, Kaleidos. The strong point? A passive cooling system which does not require electricity to operate. This technology allows the reactor to shut down and cool itself, even in emergency situations.
But there’s more. Tests have shown that Kaleidos can activate complete shutdown in just 300 milliseconds. An extraordinary speed, which makes it one of the safest nuclear solutions ever designed. These revolutionary features not only promise greater safety for the management of nuclear energy, but also open up the possibility of installing microreactors in previously unthinkable contexts, such as densely populated urban areas.
A historic step: testing of microreactors by 2026
The future of Kaleidos is linked toIdaho National Laboratory (INL)the first center in the world entirely dedicated to microreactor testing. Here, starting from mid-2026, Kaleidos will be among the first projects to undergo operational trials. Meanwhile, Radiant Industries has completed the phase FEEED (Front-End Engineering and Experiment Design)a crucial piece for the commercialization of the project.
A further milestone was reached with the approval for the phase DEEP (Detailed Engineering and Experiment Design) by the US Department of Energy. This step involves the drafting of thePreliminary Documented Safety Analysis (PDSA)bringing the Kaleidos design to the 90% complete.
The real strength of microreactors like Kaleidos lies in their flexibility. Small size, advanced security and simplified management make them the ideal choice for remote communities, military bases and industrial applications. But not only that: thanks to the passive cooling system and the speed of response, they could also find space in urban areas, where large traditional reactors are unthinkable.
If Kaleidos goes live by 2026, it will be the first design of operational nuclear reactor in the United States in 50 years. This milestone would mark a historic turning point, not only for the American nuclear industry, but for the entire global energy landscape. With thenuclear energy back at the center of the debate as a sustainable alternative to fossil fuels, Kaleidos could represent a new, safer and more efficient alternative, at least on paper
