Specialised subsea drill will take on Saint-Nazaire seabed

The windfarm will be the first in the world to use drilled XL-monopile foundations.

In 2019, a consortium including DEME Offshore and Eiffage Métal was awarded an engineering, procurement, construction and installation contract for 80 foundations for the French windfarm. The scope includes the design, fabrication, transportation and installation of the foundations.

The 480-MW Saint-Nazaire offshore windfarm, owned by EDF Renewables and Enbridge, will be constructed between 12 km and 20 km off the coast of the Guérande peninsula in western France.

The XL-monopile foundations have to be installed on a difficult rocky seabed. DEME Offshore and Herrenknecht are fabricating a tailor-made subsea drill specifically for the project. The drill will be deployed from DEME Offshore’s installation vessel Innovation.

DEME Offshore general manager Bart De Pooter said, “Installing drilled XL-monopiles is a step forward in the offshore wind industry.

“With this innovative solution, developed in partnership with Herrenknecht, we will ensure the installation is completed safely and efficiently in challenging marine conditions.”