On Friday, the U.S. Nuclear Regulatory Commission (NRC) announced that it will issue certification to a new nuclear reactor design, making it the seventh nuclear reactor to be approved for use in the United States, Ars Technica reports. But in some ways, it’s a first: The design, from a company called NuScale, is a small, modular reactor that can be built at a central facility and then moved to the site where it will be operated.
The design is expected to be moved after it is approved in a final safety assessment in 2020.
Small modular reactors have been touted as avoiding many of the problems that make large nuclear plants so expensive to build. They are small enough to be assembled on the factory floor and then shipped to the sites where they will operate, eliminating many of the challenges of custom, on-site construction. In addition, their construction allows passive safety, requiring no operator action to shut down the reactor if a problem arises.
Many small modular designs involve different technologies than traditional reactors, such as using molten uranium salt as reactor fuel. NuScale has a more traditional design with fuel and control rods, and energy is delivered via boiling water. Its hands-free safety features include setting the entire reactor in a large pool, control rods inserted into the reactor by gravity in the event of a power failure, and convection-driven cooling from an external water source.
NuScale began the certification process in 2016. According to the NRC, the process required the company to submit technical information for the committee to evaluate.
"The application must closely analyze the appropriate response of the design to an accident or natural event. The application must also list inspection, testing, analysis, and acceptance criteria to verify the construction of key design features. In addition, the NRC requires design certification applicants to evaluate how the design will protect the reactor and spent fuel pool from the impact of a large commercial aircraft."
Once completed, the certification will be published in the Federal Register, allowing the design to be used in the United States. Friday’s announcement said the NRC is ready to take the publication step.
The NRC will still have to weigh in on where any of these reactors will be deployed. One such site is currently in the works: a project called the Carbon Free Power Project, which would be located at Idaho National Laboratory. The project is expected to be operational by 2030 but has been facing some financial uncertainty. Utilities that might use the electricity produced there have become hesitant to commit funds to the project.