Like factory-built homes, nuclear reactors are going modular

A rendering of a small-scale power plant.
An artist’s rendering of NuScale Power’s small modular nuclear reactor plant.
Courtesy of NuScale

Updated: Sept. 25, 3:47 p.m. | Posted: Sept. 24, 4:29 p.m.

Last October, Xcel Energy CEO Ben Fowke told Climate Cast that the Minnesota-based utility company is interested in exploring some outside-of-the-box technologies to achieve 100 percent carbon-free energy by 2050.

Now, one of them — a new kind of nuclear reactor — is a step closer to hitting the market.

The U.S. Nuclear Regulatory Commission gave its first design approval for small modular reactors, or SMRs, to a company called NuScale Power in late August. The technology shrinks the cost, footprint and, according to NuScale, the risk of traditional nuclear. And it could help utilities fill gaps in reliable energy left by wind and solar that are currently being filled by coal power plants, natural gas and old nuclear power plants.

The reactors and their 15-by-70-foot containment vessels are assembled in a factory and can power 45,000 homes. Utilities can assemble a power plant using any number of these reactors to fit their needs.

“It’ll look more like an industrial building, as opposed to the large containment domes you associate with nuclear power,” said NuScale Co-founder and Chief Technology Officer José Reyes. “We designed our plants so that we can repurpose coal fire plants, and we can also retrain many of their workers to work at a NuScale plant.”

Reyes said 12 NuScale modules would avoid more than 6 million tons of CO2 emissions a year when compared with coal power plants. A study commissioned by a utility company in the Pacific Northwest found including SMR’s in its energy mix would be the most cost-effective way to reach the state’s zero-emissions mandate.

A safety review earlier this year did cast doubt on NuScale’s claim that the reactors would successfully shut down and remain cool in the event of an accident, according to Science Magazine. Reyes told the magazine that the issue would be resolved before a plant is built.

Reyes spoke with MPR News chief meteorologist and Climate Cast host Paul Huttner. Hear their conversation using the audio player above.

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