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Fission Batteries

Could bite-size nuclear plants become go-to power sources for off-grid homes and businesses? They will if Denver-based Hyperion Power Generation can make good on its vision. About the size of an outdoor hot tub, Hyperion's 25-megawatt fission batteries potentially could be installed just about anywhere, and they need to return to Hyperion for refueling with enriched uranium only about once every eight to 10 years. They're optimized for safety too: Because liquid metal cools the reactors instead of pressurized water (which is what large fission reactors use), radioactive material would not likely spew into the air in case of an accident, says Deborah Blackwell, Hyperion's vice president of public policy. "The fuel would just sit in the bottom of the reactor and become a big paperweight, containing the radioactivity."