The Czech energy giant ČEZ has finalized its entry as a major shareholder in British company Rolls-Royce SMR, now holding a roughly 20 percent stake after completing a two-part transaction initiated earlier this year.

With the deal closed, the companies will begin work on constructing up to three small modular reactors (SMRs) in the United Kingdom and prepare for a similar project in Czechia.

ČEZ first purchased an 11 percent share in Rolls-Royce SMR in March for over 3 billion Czech crowns (€122 million). The company increased its stake to the previously announced 20 percent in July, following Rolls-Royce SMR’s selection by the British government as a preferred supplier for modular nuclear reactors in June. This milestone was a key condition for proceeding with the full investment.

“The collaboration will now continue as planned,” said ČEZ board member Tomáš Novák, as cited by Echo24. “Rolls-Royce SMR will focus on developing up to three modular units in the U.K., with ČEZ contributing as a supplier or subcontractor of specific technologies, potentially through subsidiaries like Škoda JS.”

Meanwhile, groundwork continues for Czechia’s first SMR, expected to be built at the Temelín nuclear site in the first half of the 2030s. Geological surveys have already been conducted, but Novák emphasized that the project remains in its early stages.

ČEZ also has plans to deploy modular reactors at other sites, including former coal-fired power plants such as those in Prunéřov and Dětmarovice. However, Novák confirmed that these would follow the Temelín project.

The Rolls-Royce SMR is a pressurized water reactor with a planned electrical output of 470 megawatts and a projected lifespan of at least 60 years. It employs a combination of active and passive safety systems, a design intended to ensure both efficiency and robust safety.

ČEZ has committed to deploying modular reactors with a total output of three gigawatts by 2050. This would nearly match the capacity of the country’s existing large reactors in Dukovany and Temelín, which each produce about two gigawatts.

On Thursday, ČEZ posted its operating profits for the first half of 2025, which showed profits up 7 percent year-on-year to 73.9 billion crowns (€3 billion).

“We continue to make significant strides in nuclear energy,” noted Daniel Beneš, Chairman of the Board of Directors and CEO of ČEZ.

“In the first half of the year, Elektrárna Dukovany II, in which we now have only a 20 percent stake, managed to sign a contract for the construction of two new units of the Dukovany nuclear power plant. In July, ČEZ completed its investment in the British developer of small modular reactors, Rolls-Royce SMR, thus acquiring a total of 20 percent stake.

“These are important milestones for ensuring energy security and affordable electricity in the Czech Republic,” he added.