In future offshore projects, TSCNET shareholder TenneT will continue to reduce grid connection costs through standardisation and innovative technology. For the DolWin5 offshore grid connection in the so-called DolWin cluster in the south-western part of the German Bight, the Dutch-German transmission system operator (TSO) has contracted a consortium consisting of Aibel and Keppel FELS with ABB as subcontractor with the design, engineering, procurement, construction, installation and commissioning of a 900MW offshore HVDC converter platform and an onshore converter station.
The outstanding feature of the DolWin5 project is the innovative connection concept. The innovative 66kV technology from TenneT, which will be deployed, represents a new generation of low-cost offshore grid connections. The wind turbines will be directly connected to the offshore platform without the need for separate substations for the wind turbines. This direct connection not only omits any further substations but also the 155kV three-phase power cables for linking the wind farm to the offshore platform. Instead, 66kV three-phase cables will be used.
“With DolWin5 we open a new chapter in offshore grid connection technology: For the first time, the wind turbines are directly connected to our offshore platform,” comments TenneT COO Tim Meyerjürgens and adds: “This innovative technology results in an enormous cost reduction. The new direct connection will save around €200m in macroeconomic terms.”