We are primarily tasked with providing power transmission services, system services and facilitating the energy market. Our core tasks follow from our appointment as grid operator under the Dutch 'Elektriciteitswet' (E-wet) and the German 'Energiewirtschaftsgesetz' (EnWG).
Offshore grid connection system with a power output of 900 MW in extra-high voltage direct current transmission technology
About the project
With DolWin5 TenneT realises a high voltage direct current offshore grid connection system in the German part of the North Sea. The grid connection has a transmission capacity of 900 MW. The offshore platform DolWin epsilon is located in the DolWin cluster. From there, a 100 km long sea cable leads south passing the island of Borkum on the West towards its landfall in Hamswehrum which is situated at the estuary of the Ems. From Hamswehrum a 30 km long land cable leads to the converter station in Emden. DolWin5 is to connect the wind farms Borkum Riffgrund West I and II and Northern Energy OWP West to the high voltage grid onshore.
Cost savings through innovative connection concept
DolWin5 is the first offshore grid connection system in which TenneT connects the wind turbines directly via 66 kV three phase electric power cables to the offshore platform. This innovative technology will firstly eliminate the need for the substations required so far in every wind farm. Secondly, no more 155 kV three-phase electric power cables are necessary for connecting the offshore platform of TenneT to that of the wind farm. From a macroeconomic perspective, this leads to enormous cost savings.