DNV GL to Provide Project Certification for German North Sea HVDC Platforms

DNV GL and TenneT have signed a four-year framework agreement covering project certification of new high-voltage direct current (HVDC) substations in the German North Sea.


The transmission system operator awarded DNV GL the contract following an independent EU tendering process.

The agreement includes the certification of the planned DolWin5 converter platform which features a grid connection concept for wind farms that could dramatically reduce costs for the offshore wind industry, DNV GL said.

The platform features an innovative connection concept to link, for example, the “Borkum Riffgrund West I and II” and “Northern Energy OWP West” wind farms to an offshore HVDC converter next to the wind farms. The DolWin5 concept connects the wind turbines directly to the offshore platform via 66kV cables.

This removes the need for separate substations for each wind farm and the 155kV cables previously used to connect the wind farm substation to the converter platform leading to huge cost savings, according to DNV GL. The platform is planned to start operations in 2024.

Tim Meyerjürgens, COO of TenneT, said: “This connection concept leads to an enormous cost reduction for the wind farms and the grid connection. With the 66-kV direct connection, we have developed a new generation of cost-efficient offshore grid connections for the German North Sea that will make an important contribution to the transformation of energy systems”.

Project certification will be performed according to the BSH Standard Design, in order to verify compliance with requirements of the German Federal Maritime and Hydrographic Agency (BSH).

“With the framework agreement DNV GL and TenneT are partnering in qualifying this new connection technology in Germany,” said Kim Mørk, Executive Vice President for Renewables Certification at DNV GL.

”We are already involved in over 80% of German offshore wind projects and are committed to helping the global offshore wind industry to verify new products and technologies that improve the cost effectiveness of wind power and enable the clean energy transition. To this end, we continue to write and define new standards to enable the certification of new technologies.”