September 29 -- Offshore installation firm Jan De Nul’s jack-up installation vessel Vole Au Vent has installed the final turbine on France’s very first commercial offshore wind farm.
Jan de Nul said that the project on the Saint-Nazaire Wind Farm project in France was completed significantly ahead of schedule.
The Vole Au Vent transported and installed 80 sets of 6 MW wind turbine generators for the offshore wind farm. This Saint-Nazaire Wind Farm will have, by the end of 2022, a total capacity of 480 MW, which is equivalent to 20 percent of Loire-Atlantique’s annual electricity consumption.
The jack-up vessel loaded the 6 MW wind turbines, in sets of four, at the Forme Joubert lock in the port of Saint-Nazaire and then transported the components some 7.5 miles offshore for installation on top of the foundations located on the Banc de Guérande seabed, in the northern part of the Bay of Biscay.
On April 1, the first turbine was loaded in the port. On September 5, the 80th and final turbine was successfully installed.
“The Saint-Nazaire wind farm is a milestone project for Jan De Nul, as this is France’s first offshore wind farm. We are proud to support the country in its energy transition by making possible the delivery of the first electricity produced by the very first French offshore wind farm. The exceptional installation progress has been the result of an extensive engineering process, optimized vessel preparation, and planning, and excellent collaboration with Parc éolien en mer de Saint-Nazaire and the turbine supplier GE,” Pieter Vandezande, Project Manager at the Jan De Nul Group.
The Saint-Nazaire Offshore Wind Farm will contribute to achieving the target of 40 percent renewable energy by 2030 and carbon neutrality by 2050 in France.
As for Jan De Nul, it brought its dredging and offshore wind installation expertise together to develop a unique method of construction consisting of preparatory rock fragmenting operations.
Most of the Saint-Nazaire turbines needed to be installed on an uneven, rocky seabed. Since the self-elevating jack-up vessel used during the project needs a stable seabed to safely jack on, some additional rock fragmenting operations were required to prepare the seabed for jacking.
In the summer of 2021, Jan De Nul’s ocean-going Cutter Suction Dredger Fernão de Magalhães performed these preparatory works. The dredger fragmented the seabed using her rotating cutter head to smooth the seabed which then allows the Vole Au Vent to perform jacking activities.