The first jacket of TenneT's Hollandse Kust (zuid) offshore platform has been installed successfully in the seabed. The heavyweight Alpha jacket of 3200 tons was transported by the heavy lifting crane vessel - the Sleipnir – in the wind farm area on Saturday 5 September. The jacket will be further installed in the next days.
The jacket is 29 meters long, 20 meters wide and 46 meters high. It is the foundation for the first of two transformer substations for the wind farm Hollandse Kust (zuid). 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. In 2021, the top side 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.
Offshore schematic presentation offshore grid wind energy to 2023
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 realised 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 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. TenneT COO Tim Meyerjürgens: "Such standardisation enables TenneT to complete these projects more efficiently, more quickly and more economically."
Offshore Grid Programme 2024-2030
According to the Follow-up Roadmap for Offshore Wind Energy, a further 6.1 GW (6,100 MW) of offshore wind farms will be built from 2024 through to the end of 2030. These wind farms will be located in the wind energy areas known as Hollandse Kust (west), Ten Noorden van de Waddeneilanden and IJmuiden Ver. For the first two, TenneT will again be using three standardised 700 MW platforms (2.1 GW). The efficient connection of wind energy areas further out into the North Sea, such as IJmuiden Far (4 GW), will partly require other technologies that use direct current instead of alternating current. IJmuiden Ver will have two offshore converter stations, each with a capacity of 2 GW, which is unique in the offshore wind industry.
Offshore grid connections Germany
In the German part of the North Sea, TenneT's 7.1 GW current connection capacities already exceeds the German government's target for 2020. This target has been set at around 6.5 gigawatts for the North Sea and the Baltic Sea together. Until 2030, TenneT' s offshore grid connection capacity in Germany will be increased to around 17 GW.