With the milestone sail-out of the 900 MW offshore platform DolWin kappa from Dragados Offshore shipyard in Cádiz, Spain, TenneT will be bringing even more environmentally friendly wind power from the German North Sea to land via the direct current connection DolWin6.
The platform has only been in construction for three years and is currently traveling to the Dutch port of Rotterdam on the transport barge Iron Lady. The Pioneering Spirit, the largest service vessel in the world, will then transport it to the installation site after being reloaded there. In 2023, the grid connection system is expected to be put into operation and will supply more than 1 million homes with renewable energy.
The platform is made up of a superstructure and a foundation structure (jacket) (topside). The platform will rise about 53 meters above the North Sea’s surface because the two are about 82 meters tall together. In order to utilize the parent platform’s existing infrastructure effectively, a bridge connecting DolWin kappa with DolWin beta (the grid connection system DolWin2), which was already launched in 2016, will be added.
The platform will be reloaded onto the biggest service vessel in the world once it reaches Rotterdam. All platform components will be transported to their final location in the German North Sea by the 382-meter-long Pioneering Spirit. Once there, the work boat will be used to install DolWin kappa.
When the platform is put into operation in 2023, it will transform the alternating current produced by offshore wind farms into direct current. This direct current will then be sent to Hilgenriedersiel on the mainland via a subsea cable that is about 45 kilometers long. The electricity will be delivered to Emden via a land cable that will also be 45 kilometers long from the landfall in Hilgenriedersiel. In order to transform the direct current back into alternating current and then feed it into the high-voltage grid at the appropriate voltage level, TenneT constructed the Emden/Ost converter station and transformer station here on land.
Image source: TenneT