How partners in the H2Mare flagship project intend to produce hydrogen on the high seas

At sea, the conditions are ideal for generating renewable electricity. The direct production of green hydrogen from wind power in offshore facilities without grid integration can significantly reduce costs compared to onshore production. The H2Mare flagship project will therefore explore the offshore production of green hydrogen and other power-to-X products.

The picture is a sketchy representation of hydrogen production at sea with an electrolyser directly in an offshore wind turbine.
Graphic: Project Management Jülich on behalf of the BMBF

Offshore wind turbines produce considerably higher amounts of electricity more regularly than their onshore counterparts. The average nominal power of onshore wind turbines, for example, is approximately 3.5 megawatts; for offshore turbines it is 5 megawatts. The hydrogen flagship project H2Mare aims to exploit this potential by using renewable electricity offshore to produce hydrogen and its secondary products.

The future partners strive to integrate the water electrolyzer directly into a wind turbine and thus provide innovative technologies to produce green hydrogen offshore. The direct coupling of wind turbines and electrolysers will minimize the costs of hydrogen production, since infrastructure costs can be significantly reduced when a connection to the power grid is not needed. In addition, the decoupling of electrolysis and grid relieves the local grid structures. Another advantage of offshore hydrogen production compared to onshore production is that there are much larger potential areas for the generation of wind energy.

Due to the numerous advantages of offshore production, H2Mare also works on solutions to directly produce secondary products such as green methanol or green ammonia in addition to green hydrogen (i.e. offshore power-to-X). To ensure their success, the partners also aim to pursue pioneering approaches such as steam electrolysis and seawater electrolysis. Furthermore, additional carbon dioxide and nitrogen, which will be extracted from the air or seawater, are required as starting materials for the power-to-X products. In addition, solutions will be developed for outstanding issues concerning safety and potential environmental impacts as well as life cycle assessments and technology evaluations.

The H2Mare project OffgridWind creates the conditions for integrating an electrolyzer directly into a wind turbine. This requires a new type of wind turbine and a different foundation than previously used. OffgridWind is conducting research into both as well as the storage of the hydrogen produced in the wind turbine and its transport to the mainland. Moreover, OffgridWind simulates the operation and calculates the costs throughout the entire life cycle of the wind turbines for offshore hydrogen production. This makes it possible to determine under which conditions turbines – such as the one developed as part of H2Mare – can be operated profitably.

The H2Mare project H2Wind is investigating the electrolyzer that H2Mare aims to integrate into a wind turbine. This novel, compact water electrolyzer is intended to work in an efficient and virtually self-sustaining manner despite rough conditions at sea. To this end, H2Wind is developing water treatment and supply processes for electrolysis but also for the storage of the hydrogen produced. Furthermore, H2Wind simulates the operation and calculates the costs of the electrolyzer in the wind turbine. This will help to identify the conditions for operating the facility profitably.

Within the scope of the H2Mare project PtX-Wind, the offshore production of further power-to-X products – e.g. methanol and ammonia – is being tested. To this end, CO2 and nitrogen are required in addition to water, which will be extracted locally from the air or the sea. In addition, PtX-Wind focuses on steam electrolysis and seawater electrolysis. If the use of seawater electrolysis is successful, the water extracted from the sea no longer needs to be desalinated before electrolysis.

TransferWind aims to answer overarching issues concerning all H2Mare projects. This includes dealing with safety and environmental issues as well as infrastructure requirements. In addition, TransferWind combines the results of the other H2Mare projects and establishes a continuous exchange between science, industry, politics, and civil society. On this basis, measures can be drawn up to ensure the safe and secure construction and operation of future offshore facilities.

These are the partners from H2Mare (in German) 

The data shows the implementing agencies of the H2Mare partners (as of 13.12.2021).

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The diagram shows elements from each hydrogen flagship project: for the series production of electrolysers, for the transport of hydrogen and for hydrogen production at sea.
Graphic: PtJ on behalf of the BMBF

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