Siemens Energy has selected the German company Pfisterer for the supply of turnkey cable systems for the BorWin4 and DolWin4 offshore grid connections in the North Sea.
Pfisterer is in charge of implementing the entire 66 kV AC cable infrastructure between the gas-insulated switchgear (GIS) transformer and submarine cable connection on the DolWin4 and BorWin4 platforms.
This involves planning, engineering services, as well as installation and project management.
DolWin4 and BorWin4 will connect offshore wind farms in the North Sea with the onshore transmission grid. The transmitted power corresponds to the demand of a major city like Hamburg, according to Amprion.
DolWin4 is a connection that extends approximately 215 kilometers, with around 60 kilometers offshore. BorWin4 has a total route length of about 280 kilometers, including approximately 125 kilometers at sea.
The German transmission system operator (TSO) Amprion placed the main orders in 2022, with Siemens Energy and Dragados Offshore selected to supply the converter platform and Prysmian to deliver the submarine cables. The same suppliers have been selected for the BorWin4 grid connection.
The platforms for both offshore grid connection projects will be installed by Allseas, with the installation work planned to commence in 2027.
BorWin4 and DolWin4 have a transmission capacity of 900 MW each. The offshore grid connections are scheduled to go into operation in 2028.