The 900-MW DolWin kappa offshore platform for the DolWin6 grid connection has been installed in the German North Sea, off the coast of Lower Saxony, transmission system operator TenneT said on Monday.
The platform, built in the Spanish port city of Cadiz, was transported to Rotterdam at the start of August and then reloaded onto service vessel the Pioneering Spirit. It was subsequently carried to its site and installed in a 12-day campaign. The over 5,000-tonne foundation structure was installed first. After that, 10 piles were driven up to 68 metres into the seabed and attached to the jacket, TenneT explained. Installation was completed with placing the about 11,000-tonne topside on the foundation.
The 90-kilometre (56-mile)-long high-voltage direct current (HVDC) grid connection, using 45-km land cable and 45-km subsea cable, will supply offshore wind power to more than 1 million households following its commissioning in 2023.
The link will reach Hilgenriedersiel on the mainland, from where the electricity will be transmitted to Emden, where TenneT has built the Emden/Ost converter station and transformer station.
“DolWin6 is already the 13th offshore grid connection in our German portfolio and will bolster the security of supply in Germany and Europe,” commented TenneT COO Tim Meyerjuergens.