ABB has successfully commissioned the subsea transmission link connecting one of the largest offshore wind farms in Europe to the Belgian grid. The Thornton Bank project, executed for the Belgian company C-Power NV was completed on schedule.

The transmission link was constructed as part of an expansion of the Thornton Bank wind farm. In the first phase of its development, six wind turbines with a total capacity of 30 MW were built and temporarily connected to the mainland. The second and third phases of the project involved adding 48 wind turbines and connecting the complete wind farm, taking its overall capacity to 325 MW. The transformer station platform collecting and transmitting the power to the coast of Belgium is situated 30 km offshore in the North Sea.
As part of the turnkey project, ABB was responsible for the system engineering, design, supply and commissioning of the AC subsea cables, the land-based cable systems and the offshore substation and platform that houses it. The wind turbines are connected via underwater medium-voltage cables to the offshore transformer station and connected to the mainland grid at 150 kV. The electricity is then fed into the grid at the Slijkens high-voltage substation located at Bredene, about 3 km inland.

The wind farm has a design generating capacity of more than 1000 GWh per year, and will contribute approximately 7 % of Belgium’s targeted renewable energy commitment by 2020. The Thornton Bank wind farm helps avoid CO2 emissions of approximately 415 000 tons per year compared to a conventional gas-fuelled plant.