The main partners in the project, known as Vertiwind, are the Lille-based designer, Nénuphar; Technip, which is also involved with the HyWind floating turbine; and EDF Energies Nouvelles, the renewables arm of French utility EDF.
The project received a major boost recently when it was awarded a grant of EUR7 million under the French government's "Investing in the Future" program, which supports innovative renewable and decarbonised energy projects.
Vertiwind consists of a direct drive machine around 90 meters tall mounted on a triangular structure tethered to the seabed. Technip is responsible for designing the platform, mooring system and connection cable as well as on-site installation.
"Our concept offers the cheapest and most reliable floating wind turbine: no massive tower and nacelle, no yaw system, no pitch system, no gearbox, no complex blade geometry," said Charles Smadja, CEO of Nénuphar.
The low centre of gravity makes the machine more stable and minimises the gyroscopic effects, the company claims. It also means the floating platform is cheaper and the whole unit can be assembled quayside and delivered by tug boat, with no need for special cranes.
This allows shorter delivery and installation times -- up to nine months faster, according to Smadja -- and lower operation-and-maintenance costs, plus increased availability, compared to other offshore turbines.
"Eventually, Nénuphar's target price per MW is expected to be comparable with the current price per MW for the conventional bottom-mounted offshore wind installations, while it allows the development of wind farms in much greater water depths," the company says.
Nénuphar plans to build a full-size onshore prototype this year and to conduct sea tests of a 2MW offshore prototype under the Vertiwind project in 2013.