A major fabrication milestone has been completed on the BorWin6 offshore grid connection project, with the successful loadout of the offshore converter topside jacket in Jebel Ali, United Arab Emirates.
Heavy lift specialist Mammoet has completed the transport, loadout and mooring of the 5,461-tonne offshore jacket foundation. The structure will support the BorWin6 offshore converter platform, BorWin kappa, which will be installed in the German North Sea.
The BorWin6 project is being developed by TenneT and delivered by McDermott International. Once operational, the 980-megawatt high voltage direct current (HVDC) connection will transmit offshore wind power from the German North Sea to the mainland, strengthening grid capacity and supporting the transition to sustainable energy.
Mammoet was selected as a subcontractor to support McDermott’s engineering, procurement, construction and installation scope for the BorWin6 topside and jacket. Its work includes critical jacking, transport and loadout services.
For the jacket delivery, Mammoet transported the structure using 216 axle lines of self-propelled modular transporters (SPMTs), powered by four power pack units. This configuration provided the drive power and steering control required to safely move the structure during the loadout operation.
Mammoet winches were also used to support safe mooring management during critical quay activities. Following completion of the loadout, the jacket and its foundation piles were secured for sailaway to Europe, where the next phase of the project will take place.
With the jacket milestone complete, attention is now turning to the next stage of yard activities. Later in 2026, Mammoet will carry out the jack up and weighing of the BorWin6 topside, which is expected to weigh approximately 17,000 tonnes.
For this operation, Mammoet will use its Mega Jack System, which is designed to allow large modules to be constructed and lifted in a single piece. The system has previously been used for lifts in excess of 40,000 tonnes and will prepare the topside for skidded loadout and sailaway later in the year.
“This jacket loadout is an important step for BorWin6 and it reflects the level of planning and control needed in a busy fabrication environment,” said Tom Brazier, Mammoet Project Manager.
“As the project moves into its next phases, our team is now focused on preparing for the upcoming jack up, weighing and loadout of the topside later in 2026.
“The Mega Jack 5200 system will be used to provide the control and stability required to handle a structure of this size,” he said.
The latest milestone builds on earlier BorWin6 work completed by Mammoet at the Jebel Ali yard. In 2025, the company carried out the movement of the topside module from its construction position to an interim staging area, setting the foundation for the next phases of the project.