Eiffage has been awarded the contract for three substations for the Bretagne Sud, Narbonnaise Sud-Hérault and Golfe de Fos French offshore wind farms, worth more than €1.5 billion

Vélizy-Villacoublay, 29 September 2025

5:40 pm

Press release

Eiffage has been awarded the contract for three substations  for the Bretagne Sud, Narbonnaise Sud-Hérault and Golfe de Fos  French offshore wind farms, worth more than €1.5 billion  

 

Eiffage, through Smulders (Eiffage Métal’s subsidiary in Belgium), has been awarded by RTE, France’s transmission system operator, an EPCIC (Engineering, Procurement, Construction, Installation and Commissioning) contract to develop and build three alternating current substations for connections to the Bretagne Sud (AO5), Narbonnaise Sud-Hérault and Golfe de Fos (AO6) French offshore wind farms and their future extensions (A09). Overall, the contract is worth more than €1.5 billion.  

The contract covers the construction of jacket foundations and topside structures, which house the electrical equipment. The jackets will be 115 meters high, 25 meters wide and 35 meters long for the Bretagne Sud project, and approximately 110 meters high, 45 meters wide and 50 meters long for the Narbonnaise Sud-Hérault and Fos projects. The topsides structures will weigh approximately 5,000 tonnes and measure over 20 meters high, 35 meters wide, and 70 meters long.

Each substation will have a 750 MW capacity. Overall, these three substations will handle the connection to the power transmission grid of more than 2 GW of decarbonised electricity, making a significant contribution towards the achievement of Europe’s net zero carbon and energy transition goals. 

The various components of these substations will be entirely manufactured in the factories of Smulders and its industrial partners in France and Europe. The jackets will be assembled at Eiffage Métal’s site in Fos-sur-Mer (France) and the topsides will be assembled at the site in Vlissingen (Netherlands).

This new project reflects RTE’s stated desire to mobilise France’s and Europe’s industrial base in order to structure an industrial cluster focused around offshore wind farm connections and thereby to increase the economic benefits for the French territories. 

The project also strengthens Eiffage’s position as a European player in renewable energy development and its strategy of building a stronger presence in offshore wind following its recent acquisition of HSM Offshore Energy. Smulders has already completed 40 substations and manufactured over 2,500 transition pieces. Leveraging its various areas of expertise, the Group has been involved in wind farm projects such as Dogger Bank, Hollandse Kust, SaintNazaire and Provence Grand Large.

 

 

 

About Eiffage

Eiffage is one of Europe’s leading construction and concessions companies. The Group’s activities are organised around the following business lines: construction, property development and urban development, roads, civil engineering and metallic construction, energy systems and concessions. Thanks to the experience of its more than 84,400 employees, Eiffage generated revenue of €23.4 billion in 2024, of which 34% was outside France.

About Eiffage Métal 

Eiffage Métal is the Eiffage group’s brand dedicated to turnkey metallic construction. Its teams design and build major structures, building facades and engineering structures. Eiffage Métal is an industry leader, particularly in the offshore wind sector, and specialises in complex, multi-technical projects. With a significant presence in Europe and worldwide, across nine production plants, Eiffage Métal employs more than 2,000 people.

Press contact

Bénédicte Dao

Tel.: +33 1 71 59 22 28 benedicte.dao@eiffage.com