Swedish utility Vattenfall has taken a significant stride in its quest to build new nuclear capacity, narrowing its small modular reactor (SMR) supplier selection to two finalists: GE Vernova Hitachi Nuclear Energy’s (GVH) BWRX-300 and the Rolls-Royce SMR. This decision marks a pivotal moment in what could become Sweden’s first new nuclear build project in over four decades, potentially setting a precedent for the European energy landscape.
The utility’s board formally decided in July 2025 to proceed with the project, citing the need to meet rising electricity demand, bolster energy security, and advance the country’s net-zero targets. The selection process, which began in 2024 with 75 potential suppliers, has been rigorous and methodical. The shortlist initially included four candidates, but Vattenfall has now honed in on the BWRX-300 and Rolls-Royce SMR designs, which could provide a total output of 1,500 MWe.
“Our goal is a successful project on the Värö Peninsula, and by that we mean that there are conditions to get it into operation within a reasonable time and budget on the site we have at our disposal,” said Anna Borg, Vattenfall president and CEO. “A successful project also lays the foundation for more nuclear power projects. We are already looking at the next step to be able to build additional reactors where Ringhals 1 and 2 are located today.”
The choice of SMRs over large-scale designs is driven by site constraints. The Värö Peninsula, home to the Ringhals nuclear power plant, is cramped and hosts ongoing life extension projects for Ringhals 3 and 4. SMRs offer a more manageable solution, requiring fewer construction workers and less construction area, thereby reducing the risk of delays and increased costs.
“Building a series of smaller units provides clear cost advantages; they take up less space, require a significantly smaller workforce and involve more manageable logistics. It also increases the possibility of finding, housing and transporting employees during the construction phase, which reduces the risk of increased costs,” said Desirée Comstedt, head of New Nuclear Power at Vattenfall.
The BWRX-300 has established itself as a frontrunner in the race to deploy SMRs in the West. Construction of the first unit is underway at Ontario Power Generation’s Darlington site near Toronto, with commercial operation expected by the end of the decade. In the U.S., the Tennessee Valley Authority has submitted a construction permit application for deployment at its Clinch River site. GVH highlights the BWRX-300’s competitive advantage, leveraging licensed fuel designs and proven boiling water reactor technology, avoiding the high-assay low-enriched uranium (HALEU) requirements that constrain competing designs.
Meanwhile, the Rolls-Royce SMR has gained significant traction through strategic government and utility partnerships across Europe. The UK design stands as the continent’s leading SMR technology with a clear pathway to mid-2030s deployment. Recent strategic agreements with key suppliers point to a maturation of its European supply chain, positioning the Czech Republic to become one of the first countries to host the UK-designed SMR by the mid-2030s.
Financing and next steps remain critical. Vattenfall will now negotiate a final supplier selection between GE Vernova and Rolls-Royce and submit an application for state risk-sharing. The utility is also looking at building another 1 GW in a “next step” on a site near Ringhals 1 and 2, with final investment decisions to be made later in the process.
This development could shape the future of nuclear energy in Europe, demonstrating the viability of SMRs in meeting energy demands and achieving net-zero targets. The success of this project could pave the way for more nuclear power initiatives, not just in Sweden but across the continent.