Hydrogen from seawater

Offshore production of hydrogen using renewable electricity offers many opportunities for the future energy system. In the seawater-to-hydrogen project, (Sea2H2), Wageningen researchers and project partner Hydron Energy make ultrapure water from seawater which is subsequently electrochemically converted by Hydron Energy into hydrogen.

End-of-life platforms offer opportunities

The ongoing rapid extension of the offshore wind energy capacity in the North Sea area combined with the envisioned decommissioning of end-of-life oil and gas platforms. This offers opportunities for offshore hydrogen production by means of water electrolysis installations. Large scale hydrogen production on offshore locations powered by renewable electricity from offshore wind and solar farms can benefit from existing gas infrastructure. They can decrease transport costs and avoid large investments in electrical grids, since transporting gases is less expensive than transporting electricity additionally already existing gas infra structure can be used. Although very promising, offshore hydrogen production by means of water electrolysis does impose technical and economic challenges.

First of all, electrolysis technology is currently too expensive for cost-competitive hydrogen production. Secondly, the electrolysis process requires ultrapure water, which is an expensive feedstock.

Hydrogen from seawater
Hydrogen from seawater

Decreasing investment and operating costs

To fully capture the potential of offshore green hydrogen production, both investment and operating costs of ultrapure water production and water electrolysers need to be decreased. To make this possible, Wageningen researchers and Hydron Energy want to demonstrate the technical, ecological and economic feasibility of producing hydrogen from seawater via a hybrid technology based on cascading membrane distillation and water electrolysis.

The ultimate goal is to lower the cost of green hydrogen production from the current level of 4 to 10 euro per kg H2 towards 2 euro per kg H2 in 2050. The project goal of SEA2H2 is to develop and test an integrated pre-pilot installation. The researchers envision that after the completion of the project a scaled-up pilot project will be initiated