FLOATING OFFSHORE WIND POWER

Patent publication No.: 3108953

“SUPPORT STRUCTURE FOR THE INSTALLATION OF WIND ENERGY CAPTURE MODULES”

(STRUCTURE PORTEUSE D’INSTALLATION DE MODULES DE CAPTAGE D’ÉNERGIE ÉOLIENNE)

The present invention relates to a support structure designed to improve the installation of wind turbines.

In its various embodiments, the concept applies to the installation of fixed-bottom wind turbines,
whether onshore or offshore, as well as to the installation of floating wind turbines.

HydreManche® raft concept adapted for floating wind turbines

Current installation techniques

Floating offshore wind turbines are installed individually using very large floats and ballast systems
designed to maintain their vertical position. They are held in place by substantial mooring systems,
which may become complex depending on the depth of the site.

How is the “floating wind turbine” version innovative?

It addresses many of the objections commonly raised in connection with wind turbine installation.

The HydreManche® raft can reduce, or even eliminate, the drawbacks mentioned above because it forms
a shared, broadly horizontal support structure that maintains and positions the wind turbines and,
where required, ensures their vertical alignment.

Each wind turbine contributes to the stability of the adjacent machines, either through its own weight
or through its buoyancy. The wind turbines are connected to the rest of the support structure by means
of articulated joints or sliding systems. Crossbeams, longitudinal members or, where appropriate, cables
connect the wind turbines either to one another or to floating caissons.

Where strict vertical alignment is required, it is ensured by bearing on a shared support structure.

The raft as a whole, substantially horizontal, is articulated so that it can adapt to wave conditions.
The structural members connecting the machines to one another may be supplemented by systems allowing
vertical oscillations or slight variations in distance between the different wind turbines, as well as
by ballast systems reinforcing the buoyancy and overall horizontality of the raft.

Where necessary, these members may be submerged at a depth compatible with the passage of vessels
having a defined draught.

The systems used to damp structural deformation or the vertical oscillation of floating wind turbines
may also enable the recovery of wave energy, through the use of hydraulic cylinders or mass-transfer
devices.

Where appropriate, the HydreManche® raft, whether fitted with its wind turbines or not, may be towed
to the installation site and then moored or anchored to the seabed.

By making it possible to mutualise and optimise both the electrical connection and the mooring or
anchoring of the machines, this process helps reduce the environmental impact of offshore installations.