TenneT has signed multi-year framework agreements with Allseas and Heerema Marine Contractors for transport and installation of at least fourteen 2 gigawatt (2GW) offshore platforms. The fourteen 2GW converter stations will be installed in the Dutch and German parts of the North Sea. The framework agreement covers at least twenty-eight slots until 2031; fourteen slots for transport and installation of a jacket and fourteen slots for transport and installation of a topside.

Heerema will deploy the Semi-Submersible Crane Vessel (SSCV) Sleipnir as well as an owned floatover barge, Allseas will use its single-lift installation vessel Pioneering Spirit for the installation of the jackets and topsides. Both vessels have been used several times in recent years to install jackets and topsides for TenneT in the Dutch and German North Sea. Heerema has been awarded about 60% of the available slots, while Allseas has been awarded approximately 40% of the slots. Additional work can be added to the awarded contracts. The awarded slots are not linked to specific 2 GW projects. The HVDC suppliers building the jackets and topsides for TenneT (Hitachi Energy/Petrofac, GE/Sembcorp, GE/McDermott and Siemens/Dragados) can choose from the suppliers whereby Heerema and Allseas can install both jackets and topsides. 

Boskalis will act as a subcontractor to Allseas, building one or two new transport vessels specifically for the 2GW Program that will meet the most stringent future legislation standards on sustainability and emissions.

KeyFacts Energy Industry Directory: TenneT