TL;DR
Nuclear reactors are getting small, and two of the smallest American designs are now one review away from switching on. In October the Department of Energy approved the safety analyses for Radiant's Kaleidos, a 1-megawatt reactor (roughly enough electricity for several hundred homes) cooled by helium and fueled with grains of uranium sealed in ceramic shells, and for a pilot reactor Last Energy is building at Texas A&M. Each is now at step four of a five-step process, with only a readiness review left before startup. A third company, Antares, cleared an earlier step for its first electricity-making design. These reactors are built for places such as military bases, where a small plant of their own, with no long power line to the outside, could change what is possible. The approvals are reported by Nuclear News, a secondary report. To see our odds on when these tiny reactors start up, and the timeline of breakthroughs from the first chain reaction to a reactor powering a base, subscribe.
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