Is combo with floating wind and hydrogen road to commercial-scale wave energy in Wales?

A new project has been launched in Wales to explore combining floating wind turbines, equipped with electrolyzers that produce green hydrogen, and wave energy devices to drive wave energy deployment off the coast of Pembrokeshire and lower its cost by sharing infrastructure.

The Milford Haven: Hydrogen Kingdom project is investigating whether sharing offshore infrastructure between wave energy converters (WECs) and up to nine 15 MW floating offshore wind turbines, each with an integrated electrolyser, can deliver a credible, bankable revenue pathway for commercial-scale wave energy in Wales.

The proposed development is located inside the Pembrokeshire Demonstration Zone (PDZ), a 90 km2 Crown Estate lease, positioned some 15 kilometers south-west of Milford Haven.

Marine Energy Wales, which supported the Innovate UK project, notes that the concept is especially attractive as wave devices could plug into the same system that wind uses, making the power cheaper to deliver, instead of each project developing its own consent and energy export infrastructure. Energy would be brought ashore as hydrogen rather than electricity, bringing extra financial benefits if industrial users are willing to pay a higher premium for green hydrogen. 

Deploying wave devices around just one floating wind turbine would be very costly, however, the proposed project includes nine units, each with 1.75 MW of spare electrolyser capacity, adding up to 15.75 MW in total. By spreading wave devices across all of them, the project can take advantage of economies of scale, which means costs per unit fall sharply, making wave energy far more competitive, the company said in its report.

The cost range identified in this study – £327/MWh for a 1.75 MW starter block falling to £181-206/MWh at 15.75 MW scale – shows that early deployments may need targeted financial support, while larger roll-outs can unlock economies of scale that push wave energy toward commercial viability.

The report states that every megawatt of wave energy installed could bring about £0.6 million in economic value and one or two jobs over the project’s life. A full 15.75 MW project could create around 20 long-term jobs and £9.5 million in value, as well as many more short-term construction jobs. 

However, this is not without its challenges, as only one company is truly ready to deliver wave arrays at scale right now, wave energy at the site is strong in winter but weak in summer, and storms and strong tides make the site technically challenging. 

Nine technical recommendations have been produced, outlining a pathway to move the wave-to-hydrogen concept from an idea to a plan that’s ready for serious investment, including, among others, comissioning detailed studies on how often wind “gaps” align with wave energy, publishing a clear roadmap for site readiness and consents, securing hydrogen offtake agreements to guarantee revenue, and investing in local supply chains so benefits stay in Wales.

“This concept that combines wave, floating wind and green-hydrogen infrastructure suggests that, if scaled quickly, wave energy in Pembrokeshire could finally break through to commercial viability, supporting Wales’ clean energy future and creating local economic benefits,” the report writes.