Vattenfall Narrows SMR Field to Two Finalists: GE Vernova’s BWRX-300 and Rolls-Royce SMR
Swedish utility Vattenfall has narrowed its small modular reactor (SMR) supplier selection to two finalists—GE Vernova Hitachi Nuclear Energy’s (GVH’s) BWRX-300 and the Rolls-Royce SMR—for potential construction of new nuclear capacity adjacent to its Ringhals plant site on Sweden’s Värö Peninsula. The announcement represents a critical step in what could become Sweden’s first new nuclear build project in more than 40 years.
While the utility ultimately intends to select one SMR supplier from the two finalists, the selections unveiled on Aug. 21 stem from a rigorous process Vattenfall launched in 2024 to identify potential suppliers for Sweden’s first new nuclear project. Vattenfall said the project is necessary to meet rising electricity demand, bolster energy security, and advance the country’s net-zero targets.
The Swedish utility’s board formally decided on July 18, 2025, to build the new project following an extensive evaluation process that began with 75 potential suppliers and was narrowed to four candidates in fall 2024. The shortlist included GVH’s 300-MWe BWRX-300 SMR, Rolls-Royce’s 470-MWe pressurized water SMR, a large-scale design from Westinghouse, and a large-scale design from Électricité de France (EDF).
Vattenfall on Thursday said it is now planning a project with either five BWRX-300 SMRs or three Rolls-Royce SMRs, which could provide a total output of 1,500 MWe. “For comparison, a 500 MW SMR has the same capacity as the first large-scale reactor in Oskarshamn,” which began operation in 1972 with a design output of approximately 440–494 MWe.
“Among other things, an application for state risk sharing will be submitted and a final supplier selection will be made,” the company said. However, the utility is also looking at building another 1 GW in a “next step” on a site near Ringhals 1 and 2. “Final investment decisions will be made later in the process,” it said.
“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.”
Site Constraints Drive SMR PreferenceVattenfall said it chose SMRs because the Värö Peninsula site, located in southwest Sweden just south of Gothenburg, imposes strict physical limits. The peninsula hosts the Ringhals nuclear power plant, which comprises four reactors, two of which remain in operation, and is one of the few nuclear plants to house both boiling water and pressurised water reactors. The first unit (Ringhals 1) operated from 1976 to 2020, while Ringhals 2 ran from 1975 to 2019. Ringhals 3 and Ringhals 4, commissioned in the early 1980s, remain in service and are slated for life extensions into the 2040s.
The utility said modular reactors will “have less impact on the existing operations at the Ringhals nuclear power plant compared to the alternatives, as a result of fewer construction workers on site and less construction area.” The site is “cramped,” requiring use of land in the Biskopshagen nature reserve, while Ringhals 3 and Ringhals 4 undergo life extensions to 80 years, creating overlapping, logistics-intensive operations. By selecting SMRs, Vattenfall reduces workforce needs and ensures “manageable logistics,” which it said “significantly reduces the risk of delays and increased costs.”
Although all four designs relied on proven technology, Vattenfall concluded that the SMRs offered superior characteristics, including that their modular approach “features a simplified design that incorporates learnings from previous nuclear power projects around the world.” Because no new reactor has yet been built in Europe, the utility acknowledged that “the first reactor built in Sweden will therefore involve learning costs.” SMRs may offset that by carrying lower investment costs and allowing multiple units to be built in series, transferring lessons from one to the next, it said. Vattenfall also determined that the two SMR suppliers could deliver electricity at a “relatively lower cost” than the large-scale options. Another major consideration was that all the fuel used by the original contenders “Vattenfall has experience with and has developed supply chains for.”
“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 the frontrunner in race to deploy SMRs in the West. Construction of the first unit is officially underway at Ontario Power Generation’s (OPG’s) Darlington site near Toronto following final provincial approval in May 2025. The project is expected to achieve commercial operation by the end of the decade. In the U.S., the Tennessee Valley Authority became the first U.S. utility to submit a construction permit application to the Nuclear Regulatory Commission (NRC) in May 2025 for deployment at its Clinch River site in Oak Ridge, Tennessee. The NRC is expected to complete it regulatory review in December 2026.
GVH says the BWRX-300’s competitive advantage lies in its use of licensed fuel designs and proven boiling water reactor (BWR) technology, which allow it to leverage existing supply chains and avoid the high-assay low-enriched uranium (HALEU) requirements that constrain competing designs. An international consortium including Ontario Power Generation, Tennessee Valley Authority, Duke Energy, and Synthos Green Energy in Poland are involved investing in the reactor’s standard design. TVA is also leading an $800 million U.S. Department of Energy grant application to accelerate the nation’s first SMR construction.
The Rolls-Royce SMR, meanwhile, 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. In October 2024, Czech utility ČEZ selected Rolls-Royce SMR for up to 3 GW of capacity and acquired a 20% stake in the company, followed by the signing of an Early Works Agreement in July 2025 to begin site-specific activities at the Temelín nuclear site. The 470-MWe pressurized water reactor design also recently secured selection by the UK government through Great British Energy in June 2025 for domestic deployment.
The technology’s modular construction approach leverages 90% of its components manufactured in factory conditions and limits on-site work to assembly of pre-fabricated modules, promising to drastically reduce construction schedules and project risks compared to traditional nuclear builds. Recent strategic agreements with key suppliers, including ŠKODA JS for critical component manufacturing and Curtiss-Wright for reactor protection systems, point to a maturation of its European supply chain. For now, site-specific licensing and environmental work at Temelín are positioning the Czech Republic to become one of the first countries to host the UK-designed SMR by the mid-2030s.
Vattenfall said the process will now continue on two parallel tracks: negotiating a final supplier selection between GE Vernova and Rolls-Royce and submitting an application for state risk-sharing. At the same time, the company is preparing applications under Sweden’s Environmental Code and Nuclear Activities Act, while deepening collaboration with the Industrikraft consortium, a coalition of Swedish industrial companies, to support potential co-investment.
The Industrikraft consortium, has expanded to include 17 leading Swedish industrial companies: Alfa Laval, Boliden, SKF, Stora Enso, Volvo Group, ABB, AFRY, Alleima, Billerud, Epiroc, Hitachi Energy, Höganäs AB, Saab, SSAB, Södra, Vectura, and Volvo Cars. “The process of building new nuclear power reactors has taken a big step forward and there is a clear and feasible project on the Värö Peninsula,” said Tom Erixon, Industrikraft chairman on Thursday. “Industrikraft views the development positively and will work together with Vattenfall to create the conditions for the planned co-investment in the project company.”
The announcement marks a pivotal new direction for Sweden’s nuclear policy, but it reflects broader European recognition of nuclear power’s role in decarbonization. Sweden’s government removed the country’s limit on nuclear reactor numbers in late 2023 and allocated over SEK1 billion ($97 million) in 2025 for fossil-free electricity expansion, including nuclear pilot projects.
“Our focus is now to agree with the state on the parameters of the financing and risk-sharing model and to carry out a negotiation and in-depth dialogue process with the two remaining suppliers,” Comstedt noted. “There is no turnkey solution on the market when it comes to purchasing a new nuclear power plant. Much work remains, even after a final supplier selection, where long-term, constructive and positive cooperation with the supplier will be very important.”
—Sonal Patel is a POWER senior editor (@sonalcpatel, @POWERmagazine).
powermag
