Producing hydrogen with wind turbines in the sea, the incredible bet of Lhyfe against Le Croisic

Moored in the port of Saint-Nazaire, Sealhyfe, Lhyge’s electrolyzer, the producer of green hydrogen (mounted on the Wavegem wave platform designed by the Saint-Nazaire company Geps Techno) will join the stormy and windy test site the next spring at sea. Sem-Rev, located about twenty kilometers from the coast of Le Croisic.

A space of one square kilometer, ceded by the State, forbidden to navigation and equipped since 2018 with the Floatgen floating wind turbine, connected to land, through a connection node located thirty meters deep. ” The goal of this operation is to validate offshore hydrogen production technology before considering large-scale industrial deployments by 2024.”explains Thomas Créach, technical director of Lhyfe.

Over the next six months, the now “production-ready” facility, designed with the expertise of Chantiers de l’Atlantique, will be tested on the quayside. “We want to have a point of reference and comparison in the management of marinization issues. All design and component modifications will be validated at the quayside prior to shipping the rig out to sea in March or April, when access conditions to the test site will be more favourable.”he adds.

A competitive challenge

This demonstrator, connected to the Sem Rev test site by a one and a half kilometer cable, will remain at sea for a year to validate the reliability of the production process in real conditions, on a barge that floats, moves. .. and will transmit all the data to the Lhyfe headquarters in Bouin (85), which in turn will pilot the Sealyfe platform. A complex operation whose studies for laying the cable were entrusted to the design office specializing in the field of Marine Renewable Energies (MRE) Kraken Subsea Solutions.

“Wind farms at sea are potentially 20 to 50 times larger than on land and offer two to three times less intermittency.”specifies Thomas Créach, who has been working with Chantiers de l’Atlantique for a year and a half on the marinization of the production process, that is, the means of protecting the saline environment, the management of power electronics and the optimization of remote maintenance operations to avoid going to the site. “The corrosion, the shocks, the gusts of wind, the 14 meter waves, the movement of the cables… It has nothing to do with the production of hydrogen on land. And this is a real competitive challenge for Lhyfe »recognizes Bernard Alessandrini, coordinator of the SEM-Rev.

Show that it is feasible and feasible immediately »

This learning will have allowed Lhyfe to understand the problems of navigation on the high seas, from laying the cable to obtaining permits, for hitherto indefinite operations, to the production of hydrogen at sea.

“We have done a lot of substantive work with state agencies. This will allow us to move faster on industrial-scale projects.” estimates the technical director of Lhyfe, who, with Chantiers de l’Atlantique, has developed a concept for a 100 MW platform, which can be manufactured in Saint-Nazaire. “The challenge now is to show that it is feasible and feasible immediately, in a reliable and robust way. even under the most severe conditions.”

A great financial challenge also for platforms costing several hundred million euros. In a market where we still consume 80 million tons of gray hydrogen, destined to be replaced, thinks Lhyfe “Convinced that the path of renewable hydrogen production in the sea is a perfectly adequate solution to the massive deployment of hydrogen”. When it went public last May, the company announced it was targeting a total installed capacity of 55 megawatts by 2024 in onshore units alone; of 200 MW in 2026, and a project portfolio of 5GW. “We want to add 3GW with offshore projects for 2030-2035”, indicates the technical director of Lhyfe, whose economic model aims to invest and deploy electrolyser projects in Europe.

About 90 files are in process. In this sense, the company has just opened a sixth subsidiary in Newcastle, in the north of the United Kingdom, to support its development in the markets of northern Europe (United Kingdom, Germany, the Netherlands, Belgium…). “In Europe, many countries have doubled or tripled their offshore wind ambitions. At the beginning of the year, Emmanuel Macron announced that he was targeting 40 GW by 2050 with offshore wind power. In Scotland, we are moving from a target of 6 GW in 2030 to areas open to offers of more than 15 GW.”observes Thomas Creach.

Lhyfe, this French start-up that sees itself as a world giant in renewable hydrogen


ZOOM – The structuring of the test sites in a foundation

Sought by the Ecole Centrale de Nantes fifteen years ago to test MRE technologies in real conditions, the Sem-Rev sea trial site is about to enter a new era while the four French sea trial sites (Sem-Rev Rev in Le Croisic, Paimpol-Bréhat operated by EDF for tidal turbines, Sainte-Anne du Portzic managed by Ifremer for low capacity prototypes and Seeneoh in Bordeaux for river tidal turbine power plant projects) should meet by the end of the year within the Open-C Foundation (Center for Marine Energy and Energy Networks).

Based first in Nantes, on the premises of the Ecole Centrale, it should move to its own premises at the beginning of the 2023 school year. “Now it will be she who will structure, manage and animate the entire sector with her own workforce, transferred from test sites or future contracts”. Created by ten founding members (Ecole Centrale, Ifremer, Technip, EDF, RTE, etc.), Open-C will benefit from an operating budget of €80 million over ten years to support projects of €300 to €400 million. This could also quickly accommodate the Mistral test site in Marseille and another site being sited to accommodate various 10-20 MW, or 50-100 MW, installations.

Restricted since its creation to 3.5 MW by Enedis due to the undersizing of the land facilities, the Sem-Rev site foresees an investment of 40 to 45 million euros over the next four years to now fully exploit the 10 MW of cable export presented in 2012. Baptized as Sem-Rev 2.0, it will allow the operation of a second wind turbine from next summer and the creation of satellite substations that will offer connection points on the surface for the reception of smaller projects, such as those of Lhyfe or others, around floating photovoltaics. Sem-Rev 2.0 should also be accompanied by an MRE exhibition center and a business incubator dedicated to this sector.