TenneT selects NKT and Prysmian to make Dutch offshore cable connections


The Netherlands – TenneT has chosen the two parties to implement five cable connections from offshore wind farms to the Dutch mainland. Using the new 2GW standard in these projects will be NKT and Prysmian.

To implement the cable connections for IJmuiden Ver Beta, IJmuiden Ver Gamma, and Nederwiek 2, which will touch down on the Maasvlakte, TenneT has chosen NKT. For the cable connections of IJmuiden Ver Alpha and Nederwiek 1, landfall in the Sloe region, Prysmian has been chosen (Zeeland). The contracts cover design, engineering, manufacturing, supply, project management, installation of 525 kV HVDC cables offshore, nearshore, and inshore, as well as all connection work in subsea and land parts.

The Italian Prysmian Group’s contract is worth 1.8 billion euros. About two billion euros for NKT.

Using reclaimed copper

The parties anticipate beginning the initial work this year. Work on laying cables will start onshore in 2025 and offshore in 2026, according to expectations. It’s anticipated that all links would be operational between 2028 and 2030. Suppliers will use reclaimed copper in an effort to lessen their carbon footprint. The cable suppliers will make any necessary investments in new production equipment, ships, and trenchers (vehicles that can bury the cables in the seabed).

Research and development

An offshore cable system using extruded insulation types and operating at a voltage level of 525 kV HVDC is necessary to transfer the 2GW of required electricity. With only one cable system, the design of the 2 GW direct current (HVDC) link, based on a 525 kV cable, limits the impact on the environment and the neighborhood. Four cables make up the cable system: a fiber optic cable, a metallic return cable, and plus and minus pole cables. TenneT launched a research and development project for the 525 kV XLPE HVDC cable system in 2020 in collaboration with market participants.


A generic platform was created with a design and layout study for the offshore platform to enable interoperability of the proprietary solutions of all HVDC manufacturers taking part in the R&D phase. The close collaboration between TenneT and the market participants has provided insights into the necessary performance and functionality of the ground-breaking HVDC system and has culminated in the certification of the cable providers in 2022.