Saint-Nazaire

Saint-Nazaire Offshore Wind Farm Profile

Location

The Saint-Nazaire Offshore Wind Farm is located approximately 12 kilometers offshore from the Guérande peninsula in the Loire-Atlantique region of Brittany, western France, within the Bay of Biscay.

Project Overview

This is France's first commercial-scale offshore wind farm, marking a significant milestone in the country's transition to offshore wind power. The project was developed by Eolien Maritime France (EMF), a joint venture between EDF Renewables, Enbridge Inc, and Canada Pension Plan Investment Board (CPP Investments), with ownership stakes of 50%, 25.5%, and 24.5% respectively.

Capacity and Turbines

The wind farm consists of 80 wind turbines, each with a capacity of 6 megawatts (MW), provided by GE Renewable Energy. The turbines are of the Haliade 150-6MW model, featuring a rotor diameter of 150 meters and a swept area of 17,860 square meters. Each turbine has blades stretching 73.50 meters and employs a Pure Torque design with a direct drive permanent magnet generator for enhanced efficiency.

Foundations and Installation

The turbines are installed on monopile foundations at water depths between 12 and 25 meters. The installation process involved preparatory rock fragmenting operations due to the uneven rocky seabed. Jan De Nul Group's ocean-going Cutter Suction Dredger Fernão de Magalhães performed these operations to smooth the seabed, allowing the self-elevating jack-up vessel Vole au vent to safely install the turbines.

Construction and Operational Timeline

• Construction commenced in September 2019.
• The first turbine was erected in April 2022.
• The installation of all 80 turbines was completed by September 5, 2022.
• The wind farm entered into commercial operation in November 2022.

Power Transmission and Grid Connection

The electricity generated is transmitted through a 33-kilometer submarine link and a 27-kilometer underground link to the onshore substation in Prinquiau. The substation, manufactured by GE Renewable Energy’s Grid Solutions’ AC Systems division, includes high and medium voltage systems, gas-insulated switchgears, and transformers. The power is evacuated to the national grid operated by Réseau de Transport d’Électricité (RTE).

Maintenance and Operations

The port of La Turballe serves as the base for operation and maintenance activities. The site includes a control room, telecommunication office, changing rooms, and a storage warehouse. Maintenance vessels are moored at the port to transfer technicians to the project site daily.

Environmental and Energy Impact

The Saint-Nazaire Offshore Wind Farm produces enough clean energy to power approximately 400,000 households and covers about 20% of the electricity consumption of the Loire-Atlantique region. This project contributes significantly to France's targets of achieving 40% renewable energy by 2030 and carbon neutrality by 2050.

Financing

The project was financed through a consortium led by EDF Renewables, with significant financial support from Natixis Corporate & Investment Banking and Groupe BPCE. The financial closing was achieved six years after the tender was awarded in 2013, highlighting the long development periods typical in such projects.

Contractors and Partners

Key contractors and partners include:

• GE Renewable Energy: Turbine supplier.
• Jan De Nul Group: Responsible for the transport and installation of turbines.
• DEME: Involved in the installation of foundations.
• Brunel: Provided HV control engineering, SCADA supervision, and commissioning services.

This project marks a crucial step in France's transition to offshore wind power, leveraging the country's extensive maritime area to harness renewable energy.