The 496MW Saint Brieuc offshore wind farm is located on the English Channel off the coast of Saint Brieuc Bay, France. It is one of the biggest commercial-scale offshore wind projects in France. Construction on the project is expected to be started in 2019, while commissioning is scheduled for 2023.
The project is being developed by Ailes Marines, a consortium of Iberdrola, RES Group, and the French public sector financial institution Caisse des Dépôts, with an estimated investment of $2.8bn.
Iberdrola holds 70% stake in Ailes Marines, while the remaining interests are held by RES Group (22.5%) and Caisse des Dépôts (7.5%).
The wind farm is expected to generate enough power to meet the daily electricity needs of more than 835,000 homes.
Saint Brieuc offshore wind farm location
The Saint Brieuc offshore wind farm will be developed on a 75km² site located approximately 16.3km off the Saint Brieuc Bay coast.
The Ailes Marines consortium was awarded the tender by the French Government to develop the wind farm, in April 2012.
Ailes Marines carried out geotechnical and geophysical surveys as well as environmental monitoring of the site during 2012 and 2013.
Saint Brieuc offshore wind farm make-up
The Saint Brieuc offshore wind farm will comprise 62 Siemens Gamesa SG 8.0-167 DD offshore wind turbines to be mounted on jacket foundations in seven rows.
The distance between the rows will be 1.3km, while that between the turbines will be 1km.
A 225kV offshore substation will also be placed on a jacket foundation in the middle of the wind farm.
Saint Brieuc offshore wind turbine details
Each of the three-bladed Siemens Gamesa SG 8.0-167 direct drive turbines to be used by the offshore wind farm will have a hub height of 207m, 81.5m-long blades, 167m-diameter rotor and a swept area of 21,900m². Each turbine will be capable of generating 8MW of electricity.
The turbines are equipped with the new High Wind Ride Through (HWRT) system, which slows down the power output instead of shutting down when wind speed exceeds 25m/s. It enables a smoother production ramp-down and more reliable power generation.
The electricity generated by each turbine will be gathered and transmitted to the offshore substation through a 66kV inter-array cable system.
The electricity from the offshore substation will further be transmitted onshore for grid connection via a 225kV export cable system.
French power transmission system operator Réseau de Transport d’Électricité (RTE) will be responsible for power evacuation from the offshore wind farm.
Siemens Gamesa was selected as the turbine supplier for the Saint Brieuc offshore wind farm in January 2018.
Atkins was awarded the front-end engineering and design (FEED) and the detailed design contract for the wind turbine jacket substructures in January 2019.
RTE is the contracting authority and project manager for the grid connection. AXYS WindSentinel was engaged for the offshore wind assessment at the Saint Brieuc offshore wind farm site.