CdA becomes key player of the European energy transition


Chantiers de l’Atlantique (CdA), one of the leaders in European maritime industry, is associated with the official inauguration of the Arkona offshore wind farm, April 16 on Rügen Island (north-east of Rostock), in the presence of Angela Merkel, federal chancellor of Germany and many other personalities.

The offshore wind farm consists of 60 wind turbines rated at 6-plus MW each, developed by the German energy company E.ON and the Norwegian company Equinor (formerly Statoil). They are connected to the electricity network by the German transmission system operator 50Hertz. Chantiers de l’Atlantique, through its Atlantic offshore energy business unit, designed, built, installed, and commissioned the largest electrical substation ever built in a single module. With a weight of more than 4,000 metric tons and a capacity of 385 MW, the substation transfers the carbon-free electricity produced by wind turbines to the equivalent of 400,000 households in Germany.

Electrical substations are key elements for the operation of offshore wind farms. These structures, often weighing more than 2,000 metric tons, transform the electricity produced by the wind turbines and can transfer it up to 100 kilometers to land. They also serve as relays for remote control of the wind farms. Fully automated, they are designed to withstand extreme marine environments, with the easiest possible maintenance.

The electrical substation at the Arkona offshore wind farm is fully automated and is designed to be able to manage the wind farm autonomously. (Courtesy: Chantiers de l’Atlantique)

Ordered in June 2015, the substation consists of a topside 50 meters long, 35 meters wide, and 15 meters high. It was designed and built by Chantiers de l’Atlantique in Saint-Nazaire (Loire- Atlantique), then transported in February 2018 by barge to its installation location in the Baltic Sea, about 35 kilometers off the coast of Rügen Island.

This “smart,” fully automated substation is designed to be able to manage the wind farm autonomously, without human intervention, thanks to a large electronic PLC system.
Chantiers de l’Atlantique also provided the foundation for the substation, a 53-meter high jacket structure with a total weight of 1,800 metric tons. The unit was delivered ahead of schedule and commissioned and to the customer in the summer of 2018.

This “turnkey” project, completed in record time, testifies to the excellent cooperation between the German, Norwegian, and French experts in marine renewable energy. It also reflects the expertise of the teams at Chantiers de l’Atlantique, who applied the processes and technologies learned through building large complex ships to design this substation, achieving weight savings of about 20 percent on the metal structure, which significantly reduced construction costs and facilitated the installation.