Heerema Marine Contractors’ semi-submersible crane vessel (SSCV), Sleipnir , has installed the jacket foundation for the BorWin kappa platform, part of TenneT’s BorWin6 offshore grid connection in the German North Sea.
Heerema carried out the work on behalf of McDermott International , which was awarded the engineering, procurement, construction and installation (EPCI) scope for the BorWin kappa topside and jacket in 2022.
McDermott started building the offshore converter platform at its Jebel Ali yard in Dubai, UAE, in July 2023. At the beginning of this year, Mammoet completed the transport, load-out and mooring of the jacket foundation for BorWin kappa at McDermott’s yard, after which the jacket and its accompanying pin piles sailed out to Europe.
The jacket, which weighs nearly 5,000 tonnes, is now fixed to the seabed with ten piles, preparing the site for the topside float over later this year, Heerema Marine Contractors said via social media.
Scheduled to go into operation in 2027, the 980 MW BorWin6 grid connection has a total length of approximately 235 kilometres, the starting point being the converter platform BorWin kappa in the North Sea, according to TenneT.
BorWin kappa will convert the three-phase current generated by offshore wind farms into direct current and transport it to the mainland through an approximately 190-kilometre-long sea cable to the landfall site in Büsum. From there, the electricity will be transmitted along 45 kilometres of underground cable to a converter station in Büttel.