Power Star Configuration: New Subsea Power Distribution System Reduces Costs For Floating Offshore Wind Farms

Fornebu, Norway - Norwegian industrial group Aker Solutions has signed a FEED (Front-End Engineering and Design) contract with the Marine Energy Test Centre (MET Centre) in Norway to test a new subsea power distribution technology. According to Aker, the technology has the potential to significantly reduce the cost and complexity of offshore wind farm projects.

As part of the project, Aker Solutions will supply the new Subsea Collector power transmission technology to the MET Centre offshore wind test area, where two floating offshore wind turbines are currently operating at a distance of approximately 10 km off the south-western coast of Karmøy, Norway. The METCentre is recognized as a world leading facility for testing new marine renewable energy technologies under various conditions. From 2026, the test area is to be expanded to seven floating turbines.

Subsea Collector is an alternative solution for electrically connecting multiple wind turbines in a star configuration instead of the traditional daisy chain concept, which according to Aker Solutions allows for greater flexibility in the architecture and construction of offshore wind farms. The design also reduces the length of cable required per turbine and farm and requires less time for vessels and installation costs. According to Aker Solutions, initial results confirm that the total cost of a 1,000 MW (1 GW) floating wind farm could be reduced by up to 10 percent.

The main component parts of the subsea collector are a 66 kV wet mate connection system provided by Benestad and a subsea switchgear with with supervisory control and data acquisition by subsea power and automation alliance partner, ABB. The installation will be carried out by the Windstaller Alliance, a cooperation between Aker Solutions, Deep Ocean and Solstad Offshore. Aker Solutions will also supply the static export cable to the mainland.

The MET Center evaluated several alternative configurations for its new cable infrastructure and ultimately decided on a pilot installation of Aker Solutions' Subsea Collector to enable the expansion of the test site.

Aker Solutions has developed the system building on its successful use of similar technologies in large installation projects and experience with subsea power solutions for subsea gas compression and more recently for floating offshore wind turbines such as Equinor's Hywind Tampen.

"This pioneering project will contribute to shaping the infrastructure in future large scale floating wind parks. The technology is under development, and the project demonstrates how Norwegian subsea expertise from the oil and gas industry drives innovation forward within floating offshore wind on a global scale,” says CEO of MET Centre and Norwegian Offshore Wind, Arvid Nesse.

Source: IWR Online, Jan 01 2024