Above: (L) Topsoe's Solid Oxide Electrolysis Cell (SOEC) technology; (R) Visualisation of a Rolls-Royce SMR plant

Netherlands-based ULC-Energy, Denmark's Topsoe and the UK's Rolls-Royce SMR have signed an agreement to jointly investigate the production of hydrogen using Topsoe's Solid Oxide Electrolysis Cell (SOEC) technology with power and heat produced by a Rolls-Royce SMR NPP.

UKC-Energy said nuclear energy combined with SOEC technology could produce clean hydrogen more cheaply than alternative electrolysis processes because:

  • The electrolysis would take place at a high temperature, reducing the amount of electricity is needed to produce hydrogen.
  • The NPPs could produce energy on average up to 95% of the time, significantly higher than alternative variable energy sources.
  • Nuclear energy can supply heat as well as electricity. By using heat directly, energy losses in the steam turbine could be avoided, increasing the effective energy capacity of the plant above its electric power rating.

The joint investigation will include a valuation of the operational flexibility of the Rolls-Royce SMR/Topsoe SOEC combination in the future green energy market. The Rolls-Royce SMR is a 470 MWe pressurised water reactor that is manufactured in modules in central factories. These are assembled under a turnkey contract on the customer site. The design has successfully completed step 1 of the UK Generic Design Assessment and is progressing with step 2.

The Rolls-Royce SMR can, when required, switch to deliver power to the grid, providing back-up to variable power sources when these sources are not available. This is expected to be a competitive solution compared with alternatives such as long duration energy storage solutions or hydrogen combustion for electricity generation.

In August 2022, Rolls-Royce SMR signed an exclusive agreement with ULC-Energy to work together to deploy Rolls-Royce SMRs in the Netherlands. ULC's aims for site selection and contract negotiations to takeplace next year, with a formal licensing application in 2025 and construction of a first SMR unit beginning in 2027 for start-up in the 2030s.

ULC-Energy CEO Dirk Rabelink said hydrogen will play an increasingly important role in balancing future energy markets. “We expect nuclear energy, especially in combination with high temperature electrolysis, to be able to produce zero-emission hydrogen competitively on a stand-alone basis. Additional value associated with the operational flexibility will further enhance the business case for this solution. We are particularly pleased that this study has been made possible by the support from a number of national and international companies,” he noted.

Jack H Carstensen, Topsoe Business Development Director said SOEC is a modular design that leverages high-temperature electrolysis that enables industrial-scale production of clean hydrogen using clean energy. “Due to the nature of the intrinsic fast-reaction kinetics and optimised conductivity found in high-temperature electrolysis. He added: “Topsoe’s SOEC technology produces more hydrogen per total power input when compared to the alternatives of alkaline and PEM electrolysis. Additionally, when coupled with a heat-producing technology such as nuclear, SOEC allows for the lowest levelised hydrogen cost with the highest level of energy efficiency.”

Harry Keeling, Rolls-Royce SMR’s Head of Industrial Markets, said production of low-cost hydrogen is a critical step on the pathway to decarbonising our wider society. “This agreement with ULC-Energy and Topsoe is an exciting step toward unleashing the potential of the Rolls-Royce SMR as its ability to flexibly provide thermal and electrical energy supports a wide range of industrial applications, chief amongst these being the large-scale generation of low-cost hydrogen.”