Xcel Energy’s Prairie Island is the probable location for the nation’s first demonstration of high-temperature steam electrolysis at a nuclear power plant. Idaho National Laboratory, which plays a key role in a hydrogen demonstration project launched last year with Xcel Energy, Energy Harbor, and Arizona Public Service (APS), announced on November 9 that Prairie Island, which houses two 550-MWe pressurized water reactors, would likely be chosen over the one-unit boiling water reactor plant at Monticello.
Minneapolis-based Xcel Energy will work with INL to demonstrate a system that uses the plant’s steam and electricity to split water. The resulting hydrogen will be used at the power plant, but excess hydrogen could be sold to other industries. Hydrogen has applications in transportation and in industrial sectors, including steel and ammonia production.
More than $10 million in federal funding for the Xcel Energy demo was announced by the Department of Energy on October 8. It is just one phase of a project that showcases collaboration between the DOE’s Office of Nuclear Energy and Office of Energy Efficiency and Renewable Energy. Commercial hydrogen production via low-temperature electrolysis is being demonstrated at Energy Harbor’s Davis-Besse plant. APS, which operates the Palo Verde generating station, will build on the Xcel Energy demo to develop an initial design and feasibility assessment for plant modifications to integrate a reversible hydrogen electrolysis system with the plant’s secondary system and will include hydrogen storage infrastructure.
Specifics: According to an October 15 article in Minneapolis’s Star Tribune, Xcel is putting $2 million of its own money into the project and will do engineering and planning work on the pilot plant through next year, with construction expected to start in 2022. It is projected to come online in 2023.
According to the project abstract, a pilot plant capable of producing about 4 kg of hydrogen per hour will first be commissioned and operated at INL. It will then be commissioned by Xcel Energy to monitor performance and interactions with the nuclear power plant and with electricity distribution systems. Connections for steam and electrical power output between the electrical grid and electrolysis unit will be developed, tested, and refined.
A recent analysis performed under the DOE’s H2@Scale initiative estimated that hydrogen produced by high-temperature steam electrolysis at a nuclear plant could be cost-competitive in the current hydrogen market.
What they’re saying: “Xcel Energy was the first major American utility to pursue a vision of 100 percent carbon-free electricity, and now we’ll be the first company to produce carbon-free hydrogen at a nuclear plant using this technology,” said Tim O’Connor, Xcel Energy’s chief generation officer. Xcel Energy has a large amount of wind in its energy generation portfolio, which offers an opportunity to demonstrate how a nuclear plant’s electricity could be used to make hydrogen when wind energy satisfies grid demand.
Richard Boardman, national technical lead for the DOE Light Water Reactor Sustainability Program’s Flexible Plant Operations and Generation Pathway, said, “This is a game-changer for both nuclear energy and carbon-free hydrogen production for numerous industries. It offers a view of the energy structures of the future, which will integrate systems to maximize energy use, generator profitability, and grid reliability, all while minimizing carbon emissions.”