Dutch offshore installation contractor Heerema Marine Contractors has installed the first jacket of TenneT's Hollandse Kust (Zuid) offshore wind farm substation in the Dutch North Sea.
Using its giant Sleipnir semi-submersible crane vessel, Heerema transported the 3200-tonne Alpha jacket to the offshore location on Saturday, September 5.
The 29 meters long, 20 meters wide, and 46 meters high jacket will serve as the foundation for the first of two transformer substations for the Vattenfall-operated 1,500 MW Hollandse Kust (Zuid) offshore wind farm.
The two 220 kV sea cables that bring the power from the wind farms ashore will be connected to the Alpha jacket in the next months, TenneT said Monday.
In 2021, the topside of the substation will be installed onto the jacket. At the end of 2021, the offshore platform is expected to be in operation. Vattenfall will use the Alpha and Beta platforms to connect the Hollandse Kust (Zuid) wind farms to the grid.
"By the end of 2023 TenneT will have constructed 3,500 MW offshore grid connections for offshore wind farms. The first 1,400 MW has been realized with the delivery of Borssele Alpha and Beta. It will then be the turn of Hollandse Kust (zuid) Alpha and Beta, followed by Hollandse Kust (noord)," Tennet said.
TenneT is using five identical 700 MW transformer platforms for these wind farms. These platforms are located close to the wind farms and all five use the same type of 220 kV cable connections to the coast, the company said.
TenneT COO Tim Meyerjürgens: "Such standardization enables TenneT to complete these projects more efficiently, more quickly and more economically."