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Sealhyfe produces its first kilos of green H2 in the Atlantic Ocean

Lhyfe, one of the world’s pioneers in green and renewable H2 production, has announced that its offshore H2 production pilot, known as Sealhyfe, was successfully towed 20 kilometers out into the Atlantic and connected with the SEM-REV power hub. As of June 20, 2023, the platform began producing its first kilos of offshore H2, marking a decisive milestone for the future of the sector. The progress of the Sealhyfe trial once again demonstrates Lhyfe’s ability to bring about concrete advances in the H2 industry and at great strides.

In launching the world’s first offshore H2 production pilot, Lhyfe wanted to prove the technical feasibility of such a project and acquire the operational experience needed to quickly scale up.

On the right : Sealhyfe offshore hydrogen production pilot (Lhyfe), on WAVEGEM platform (GEPS Techno), On the left : FLOATGEN floating turbine (BW Ideol).

The company therefore voluntarily chose to confront Sealhyfe with the toughest conditions. It will be tested under real conditions, on a floating platform, which has been re-engineered to stabilize the production unit at sea (the WAVEGEM platform, engineered by GEPS Techno), and connected to Central Nantes’ SEM-REV offshore testing hub operated by the OPEN-C Foundation, which is already linked with a floating wine turbine (FLOATGEN, engineered and operated by BW Ideol).

For this, Lhyfe and its partners designed, built and assembled all the technology necessary for producing H2 offshore, including the 1-MW electrolyzer supplied by Plug, in just 16 months. The Sealhyfe platform, which is less than 200 sq. meters in area, can produce up to 400 kg/d of H2.

From September 2022 to May 2023, Sealhyfe was moored at the Quai des Frégates, in the Port of Saint-Nazaire. Lhyfe and its partners have thus been able to draw knowledge from a series of startup tests to approach the second phase of the project with confidence and get the most out of the trials. Tests included:

  • Benchmarking tests. Hundreds of tests were carried out at quay recording the precise behavior and performance of the platform, so that they can be compared with the Phase 2 trial results via the thousands of sensors installed on the platform.
  • Technology and system optimization. All the technology has been adapted to operate offshore in extreme conditions and designed to minimize the number of maintenance interventions required at sea. The tests performed at quay allowed Lhyfe to further optimize and approve the technology’s behavior.
  • Development of key solutions. Lhyfe also developed the software and algorithm building blocks necessary to manage the site remotely. It will operate fully autonomously, more than 20 kilometers off the coast and in connection with the SEM-REV testing site’s subsea hub.

Following this first phase, Lhyfe has already updated its specifications for all its sites—on and offshore—so that they can apply this valuable expertise. All Lhyfe units will therefore benefit from the state of-the-art operating optimizations trialed under this experiment.

Sealhyfe was towed this 19 May to the SEM-REV offshore testing site, 20 kilometers off the coast of Le Croisic (France). It was then connected to the site’s subsea hub via a dedicated umbilical cable that was specially designed for H2 application. The system was restarted and on stream in just 48 hours.

Lhyfe will now reproduce all the tests carried out at quay several times to have a strict comparison of results and will then tackle additional offshore-specific tests. In achieving the reliable offshore production of H2 in an isolated environment, the company will develop a unique operating capability which involves managing the platform’s movement and environmental stresses and validating green and renewable H2 production software and algorithms.

As a logical follow-up to this first stage, Lhyfe just announced that the HOPE project, which it is coordinating as part of a consortium of nine partners, has been selected by the European Commission under the European Clean H2 Partnership and is being awarded a €20-MM grant. With HOPE, Lhyfe and its partners are moving up a gear and aiming for commercialization.

This unprecedentedly large-scale project (10 MW) will be able to produce up to 4 tpd of green H2 at sea, which will be exported ashore by pipeline, and then compressed and delivered to customers.

Through these two pioneering projects in offshore H2 production, Lhyfe aims to validate industrial solutions which it will submit in response to future calls for projects from various governments, to help achieve the target set by the European Commission as part of the REPowerEU plan of 10 MMt of clean H2 produced in the European Union by 2030. To achieve this, Lhyfe has already signed partnership agreements with wind turbine developers and offshore power specialists, such as EDPR, Centrica and Capital Energy.

Matthieu Guesné, Founder and CEO of Lhyfe said, “Our team—supported brilliantly by our partners—has achieved a genuine feat of technology in successfully designing this first floating green H2 production site. We are extremely proud to be the first in the world to produce H2 at sea. This has been our wish since the launch of the company and we continue to move very quickly offshore, which for us represents a tremendous development opportunity for mass producing H2 and decarbonizing industry and transport. We are continuing to build on the successes we have had so far, firstly to prove to the world that transition is possible today, and of course to accelerate it.”

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