The Saint-Nazaire Offshore Wind Project is a 480MW offshore wind farm located in the Loire-Atlantique region of coastal France. The project became completely operational in November 2022.

EDF Renewables and EIH SARL, which is owned by Enbridge and Canada Pension Plan Investment Board (CPP Investments), are the joint owners of the offshore wind farm.

The €2bn project will generate equivalent electricity to meet nearly 20% of Loire-Atlantique’s annual consumption, and power around 400,000 homes. It will also help France to reach its target of meeting 33% of its energy requirements from renewable sources by 2030.

Around 100 people are employed to support the operation and maintenance of the wind farm.

Location

The Saint-Nazaire Offshore Wind Farm, also known as Parc Eolien en mer de St Nazaire project, is located on the bench of Guérande, Loire-Atlantique in Brittany in western France.

The project’s wind turbines are located between 12km and 20km off the Loire-Atlantique coast across an area of 78km².

Water depth in the region ranges between 12m and 25m.

Development milestones

In 2012, the Government of France named Eolien Maritime France (EMF) as the winning bidder for Saint-Nazaire Offshore Wind Project.

EMF is a joint venture between EDF Renewables and Enbridge. It was also named the winner for two other offshore wind projects along the French coast- Fécamp (Seine- Maritime) and Courseulles-sur-Mer (Calvados).

Construction and operating permits for Saint-Nazaire project were issued in 2017. The final decision from France’s supreme administrative court Conseil d’Etat was awarded in June 2019.

In September 2019, the construction of the project was officially launched by EDF Renewables and EIH SARL.

The Saint-Nazaire wind farm produced the first electricity at the beginning of June 2022 and became completely operational in November 2022.

Infrastructure

The Saint-Nazaire project comprises 80 GE Haliade turbines, each having a capacity of 6MW, which gives the wind farm a combined output of 480MW.

The GE Haliade turbines have a rotor diameter of 150.95m and swept area of 17,860m2. It features three blades each with a length of 73.5m.

The wind turbines are installed 1km apart on monopole foundations. They feature the GE PURE TORQUE concept, a rotor support technology that protects the drive train from unwanted wind buffeting by deflecting it towards the tower.

The offshore turbines are also equipped with a direct drive permanent magnet generator (PMG) for reliability in the turbine’s drive train.

Power transmission

Electricity transmission system operator RTE constructed a 33km subsea link and a 27km 225kV underground line through Saint-Nazaire, Trignac, Montoir-de-Bretagne, Donges and Prinquiau to connect the offshore wind farm to the existing national grid.

The project infrastructure includes a substation in Prinquiau for the integration of the wind farm into the transmission grid.

The power generated from the wind farm will be fed into the national grid.

Contractors involved

The Saint-Nazaire Offshore Wind Project is equipped with GE Haliade 160-6MW turbines, which were manufactured in France. Each of these turbines can generate enough power to serve 5,000 homes.

In February 2022, GE renewable Energy selected Global Wind Service (GWS) as a partner for the load-out and installation of the turbines.

DEME and Eiffage Métal secured €500m Engineering, Procurement, Construction and Installation (EPCI) contract for 80 steel foundations in 2019.

COWI, an engineering and architecture consultancy, was awarded the contract for the detailed design of the monopile foundations in 2019. The consultancy had been associated with the project since the tender design in 2016.

EDF Renewables contracted Brunel for HV control engineering, Scada supervision and commissioning services of the Wind turbine generator (WTG), foundations and inter-array grid for the project.

Jan De Nul Group was responsible for the transport and installation of all wind turbines and monopiles.

SAL was engaged by offshore contractor DEME Offshore for providing logistics support for the project. This includes the use of SAL’s MV Svenja carrier for transporting the heavy foundations for the Saint-Nazaire Offshore Wind Farm.

Smulders and DEME Offshore used Enerpac hydraulic levelling and fixation systems for the installation of 80 GE Haliade 150-6MW turbines.

GE Renewable Energy’s Grid Solutions’ AC Systems division designed and integrated the high and medium voltage systems including five 220kV gas-insulated switchgear (GIS), two 220/33kV transformers, two SCADA systems, and one 33kV GIS and a telecommunications system.

In December 2019, Sif Holding received the order for 80 monopiles and the primary steel for 80 transition pieces for Saint- Nazaire wind farm.

The generators for the project were assembled at the GE Renewable Energy plant in Montoir-de-Bretagne, near Saint-Nazaire.

The 80 nacelles and the electrical substation were made in Saint-Nazaire by General Electric Renewable Energy and Chantiers de l’Atlantique, respectively.