New first for France as full‑scale wave energy demonstrator kicks off sea trials

June 15, 2026, by Melisa Cavcic

French wave energy technology developer Seaturns has embarked on a full‑scale offshore trial of its wave energy demonstrator off the Gironde estuary on the French Atlantic coast, which will be supervised through a collaboration with ESB, an Irish energy company. This project is expected to boost Europe’s wave energy capacity.

Seaturns has deployed its demonstrator in the Atlantic and announced a collaboration with ESB; Source: Seaturns

Seaturns has shed light on the deployment of its full-scale demonstrator on the French Atlantic coast, said to be a first in France, which marks the start of an offshore trial campaign of a minimum of 12 months. The program is perceived to represent a critical de-risking milestone on the company’s path to commercial deployment and technology certification by 2027.

According to the European wave energy player, the trial period will be monitored by Ireland’s ESB under an industrial innovation collaboration, providing the French firm with an industry perspective from one of Europe’s energy utilities.

Vincent Tournerie, Founder and Chairman of Seaturns, commented: “The installation of this first full-scale demonstrator marks the culmination of more than ten years of research and development by the Seaturns team. From the outset, we have followed a rigorous, step-by-step technology validation program, progressing successively through testing at scales of 1/30, 1/10, and 1/4 in collaboration with European universities and Ifremer, before reaching full scale today.

“Each phase has validated the performance and reliability of the technology under increasingly representative operational conditions. In a relatively short timeframe and with well-managed resources, we have successfully deployed our first full-scale demonstrator at sea. This milestone demonstrates the relevance of our technological approach, founded on simplicity, robustness, and industrial competitiveness, and marks a pivotal step towards commercialization.”

The deployment of the Seaturns full-scale wave energy demonstrator S1 is deemed to be a landmark moment for the wave energy sector in Europe. The trials are being conducted 27.5 kilometers away from Port of Le Verdon in Nouvelle-Aquitaine, within the jurisdiction of the Grand Port Maritime de Bordeaux (GPMB).

The location was selected for the quality and representativeness of its wave conditions relative to real offshore operating environments, whilst offering logistical access for marine operations. The demonstrator operates off-grid, and energy produced is dissipated.

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However, full turbine output data and floater behavior monitoring data will be collected throughout, forming the evidentiary basis for technology certification. An environmental impact monitoring program will run for the full duration of the trials. Seaturns claims to benefit from the institutional and technical support of the Grand Port Maritime de Bordeaux throughout this phase.

The primary objectives of the trial campaign are to validate the dynamic behavior of the floater under real sea conditions, develop and refine offshore operations and maintenance procedures, confirm the reliability and performance of the power take-off (PTO) system, and collect the data required for technology certification and industrialization.

The sea trial results are expected to support technology certification by mid-2027, with data directly informing the industrialization roadmap and the commercial development of Seaturns’ first 2 MW pilot project in Mauritius, described as a world first for the wave energy sector, with a pathway to a 10 MW commercial project.

Arthur Chauliac, Trials Manager at Seaturns, underlined: “The deployment of our full-scale wave energy demonstrator is a key milestone for Seaturns, and a first in France. The floater is fully instrumented and subject to comprehensive operational monitoring covering the principal performance criteria for marine energy technologies. Installation was carried out in two stages — the laying of the mooring line, followed by connection of the floater, which is now fully operational.

“We monitor its performance in real time using onboard data, correlated with wave conditions measured by a wave buoy. Over an 18-month period, these trials will enable us to demonstrate the performance, reliability and viability of our technology, whilst progressing towards certification and commercialization.”

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ESB will monitor the key stages of the deployment and offshore trials of Seaturn’s full-scale demonstrator, with access to technical data and live performance results under real operational conditions.

The French firm sees this partnership as a significant commercial signal, reflecting growing institutional appetite for wave energy as a bankable, scalable renewable technology, and reinforcing the potential investment case ahead of the company’s planned fundraising round in early 2027.

Cahir O’Neill, Emerging Technology Specialist at ESB, stated: “ESB are actively monitoring wave energy demonstrations progressing across a number of technologies in several European countries.

“The leading projects, including Seaturns, are addressing some of the fundamental challenges to make wave energy a mainstream energy source including storm survivability and structural efficiency. These challenges are critical to unlocking significant energy potential on the Atlantic coast of Ireland and Europe.”

Seaturns elaborates that Ireland holds one of the largest exploitable wave energy resources in Europe, with potential up to 19 GW according to the Evolve project. The SEAI Offshore Renewable Energy Technology Roadmap (2024) significant wave energy scenario has 4 GW (14 TWh per year) deployed by 2050.

Both companies view this collaboration as an opportunity to accelerate the development and adoption of wave energy as a competitive and viable renewable energy source, and to lay the groundwork for future commercial deployment, particularly in the Irish market.

ESB has been systematically monitoring the wave energy technology landscape for years as part of its net zero by 2040 strategy. Seaturns is targeting a fundraising round in early 2027 to finance its progression from TRL 6 to TRL 8, support the industrialization of its equipment and advance the project development toward commercialization.

The French wave energy technology developer underscored: “Europe leads global wave energy technology development, with an estimated resource of over 400 TWh per year.

“With a validated full-scale demonstrator now operational at sea, Seaturns is positioned to become one of the first wave energy companies globally to achieve technology certification and move into commercial deployment, representing a significant value inflection point for the company.”