Velella

An R&D project dedicated to the environmental impact of floating offshore wind.

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Funded with €5.7 million by the French Government under the "France 2030" program operated by ADEME, following the "DEMO Tase" call for projects, Velella aims to optimize several technology bricks and methods needed to prepare the deployment of commercial floating wind projects under the best economic, social and environmental conditions. Above all, this project will be a first in the MRE sector: each innovation developed will be driven by an eco-design approach, from life cycle analysis to recyclability and impact on the underwater environment. The Velella R&D project brings together several industrial and academic players: BW Ideol, as project leader, Centrale Nantes, the OPEN-C Foundation, IFREMER, ENSTA and IVM technologies.

Main activities

The project relies on the proven floating technology designed by BW Ideol to structure its research and innovation activities. Lasting 4 years, it is built around 3 main axes.

Three research and development axes

• The first axis aims to pursue efforts to optimize the economic and environmental performance of the BW Ideol floater, particularly with a view to the arrival on the market of high-capacity wind turbines (>20 MW).
• The second axis will notably involve the analysis of mooring lines made of innovative materials, and the implementation of new underwater surveillance and inspection methods to further reduce costs during operation.
• The evaluation of socio-economic impacts and the structuring of the floating wind sector will form the third axis.

Eco-design and test-sites

Finally – and this is quite unique for such a marine renewable energy project – the project is guided by an eco-design approach, where each innovation will be analyzed and assessed from the perspective of life cycle analysis (LCA), recyclability and potential consequences on the marine environment.

Tests will be carried out on various sites made available by the partners, including BW Ideol's Floatgen wind turbine, installed on the SEM-REV test site operated by the OPEN-C Foundation off Le Croisic.

Project progress

At the 9th Conference on Wind Energy and Wildlife Impacts (CWW2025) in September 2025, the OPEN-C Foundation presented the progress of the Velella project, notably regarding benthic and pelagic monitoring of the environmental impacts of floating wind. At mid-term, the project is delivering its first results, based on new environmental monitoring methods developed by the OPEN-C Foundation and IFREMER.

Benthic community monitoring campaigns are well advanced. Initial analyses show a localized sedimentary change, mainly beneath the floater, characterized by the formation of mussel shell aggregates. These shells come from mussels growing on the floater, which detach during storms or when they die.

An underwater pelagic observatory was installed on the Floatgen floater in July 2026. Designed and prepared over nearly two years, this environmental monitoring system will enable continuous scientific monitoring until the floating wind turbine is decommissioned.