The Approval

NuScale Power announced on May 29, 2025, that the U.S. Nuclear Regulatory Commission (NRC) has granted Standard Design Approval (SDA) for its uprated 250 megawatt thermal (MWt) small modular reactor modules, which generate 77 megawatts of electricity (MWe). The approval makes NuScale the only SMR developer to have received two NRC design approvals — its original 50 MWe design was certified first, and the uprated 77 MWe version now follows.

The NRC completed its review earlier than anticipated, with the application originally expected to be finalised later in summer 2025. NuScale remains the only SMR company to have received any design approval from the NRC. No other SMR developer in the United States has yet reached this regulatory milestone.

“We are thrilled that the NRC has approved our second SDA application, this time for our 77 MWe design.”

— John Hopkins, President and CEO, NuScale Power

The uprated design increases electrical output per module from 50 MWe to 77 MWe, a 54% increase in capacity. The underlying safety case and passive safety features are carried over from the previously approved design, with changes made primarily to the power output and select engineering parameters.

Design Specifications

The approved design operates at 250 MWt and delivers 77 MWe of electrical output per module. Sites can accommodate between one and twelve modules, giving a maximum combined output of 924 MWe. The modular structure allows customers to scale capacity incrementally rather than committing upfront to a large fixed-output plant.

NuScale’s design uses passive safety systems — meaning the reactor can shut down safely without operator intervention or external power, relying instead on natural convection and gravity. This was a key feature of the original 50 MWe design and has been retained in the uprated version. Intended applications include electricity generation, data centres, district heating, desalination, and industrial hydrogen production.

“NuScale is proud to have worked with the NRC and to have met its stringent regulatory application process.”

— Carrie Fosaaen, Vice President of Regulatory Affairs and Services, NuScale Power

Whether the uprated design can be deployed at competitive cost remains an open question for the company. NuScale cancelled its flagship UAMPS project in Utah in 2023, citing rising cost estimates. The NRC approval addresses regulatory risk, but construction financing, project economics, and securing off-take agreements remain challenges the company has yet to demonstrate at commercial scale.

Commercialization Outlook

The NRC completed its technical review earlier than the originally anticipated summer 2025 target date. While the approval is a meaningful regulatory step, Standard Design Approval does not authorise construction or operation of a plant — prospective operators would still need to obtain a Combined Licence (COL) from the NRC before breaking ground.

NuScale’s commercialisation strategy runs through ENTRA1 Energy, an independent power platform that holds the global exclusive rights to deploy NuScale’s SMR technology. ENTRA1 is targeting first deployment by 2030. Potential applications include electricity supply for data centres, hydrogen production, and desalination. NuScale also has an active project in Romania through RoPower, with a Front-End Engineering and Design study ongoing as of 2025.

The 2030 deployment target is ambitious given that no NuScale plant has yet entered construction. The company’s previous flagship project — a 12-module plant for the Utah Associated Municipal Power Systems — was terminated in late 2023 after projected costs rose substantially. NuScale has since refocused its commercialisation efforts through the ENTRA1 partnership. The regulatory approval strengthens NuScale’s position in contract discussions, but translating approved designs into operating plants will depend on factors including project financing, fuel supply chains, and the ability to contract customers at viable electricity prices.