Fixed-bottom wind power

Patent publication No.: 3108953

“SUPPORT STRUCTURE FOR INSTALLING WIND ENERGY CAPTURE MODULES”

This 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 wind turbines resting on the ground or seabed, whether onshore or offshore, as well as to the installation of floating wind turbines.

Fixed-bottom wind turbine version of the HydreManche® foundation structure

Offshore or onshore applications

Current installation techniques

• In general, onshore wind turbines are installed individually on substantial reinforced-concrete foundations, making end-of-life dismantling difficult and costly.

• Fixed-bottom offshore wind turbines are also installed individually, either on gravity-based foundations weighing several thousand tonnes and requiring major marine civil-engineering works on the seabed, or by means of deep drilling or piling for so-called “monopile” installations, or on jacket-type foundations, themselves fixed by drilling or piling at each leg.

Such operations are known for their high cost and significant environmental impact. They also often generate strong opposition from the local populations concerned. Here again, the dismantling phase remains a major issue.

What makes the fixed-bottom wind turbine version innovative?

It addresses many of the objections commonly raised when wind turbines are installed.

The HydreManche® foundation structure can reduce, or even eliminate, the drawbacks mentioned above, because it forms a shared, broadly horizontal load-bearing structure that keeps the wind turbines upright and ensures their positioning.

Each wind turbine contributes, through its own weight, to the stability of the adjacent machines.

The wind turbines are connected to the rest of the support structure either rigidly, through articulated links, or by means of sliding systems where the ground or seabed is not perfectly stabilised.

Beams, longitudinal members or, where appropriate, cables connect the wind turbines at the level of their tower or tower base, either to one another or to intermediate or peripheral ballast blocks.

• Since the installation of the wind turbines is no longer constrained by a strictly rigid connection to heavy foundations, it becomes possible to insert a device between the ground or seabed and the base of the modules to absorb vibrations or infrasound.

Significantly improved environmental preservation

Heavy foundations, and later their dismantling, are avoided, as is much of the associated groundworks or seabed preparation.

As a result, site development loses much of its irreversible character, making it easier to gain acceptance.