TenneT has marked a key milestone in the development of its 900MW German offshore grid connection project, BorWin5. The BorWin epsilon converter platform, which will link to EnBW’s He Dreiht offshore wind farm in the North Sea, was successfully installed on its foundation, known as the jacket, during the night.

The platform weighs approximately 12,300 tonnes—about twice the weight of the Eiffel Tower—and reaches the height of a 16-storey building. Now securely positioned at sea, the structure is nearing readiness for operational use. The next steps include connecting the subsea cable to the platform, after which trial operations will commence.

BorWin epsilon serves as the starting point of the BorWin5 grid connection system. It will receive wind energy from the offshore wind farm through a 66kV three-phase cable. The electricity generated at sea will first be converted from alternating current to direct current on the platform.

This direct current will then travel approximately 120 kilometers via a subsea cable to reach the mainland. Upon arrival, it will be converted back into three-phase current and delivered into the extra-high-voltage transmission grid.

BorWin5 is TenneT’s fourth offshore project near Borkum using extra-high voltage direct current (HVDC) transmission technology. This approach supports efficient energy transmission over long distances, reducing losses and contributing to the integration of renewable energy into the grid.

The completion of this phase brings the project significantly closer to enhancing the supply of offshore wind power to the German mainland, supporting long-term sustainability and energy goals.