Innogy and Shell have signed an agreement with Stiesdal Offshore Technologies to build a floating offshore wind turbine demonstration project in Norway.

The three companies will jointly invest €18 million in the project, which will use Stiesdal’s TetraSpar floating foundation concept and a Siemens Gamesa 3.6 MW direct drive wind turbine. The design of Stiesdal’s foundation offers considerable opportunities for cost reduction in the floating offshore sector, Innogy said.

“These are exciting times. The floating offshore wind market is evolving but until now, floating foundations have been stubbornly expensive,” said Hans Bünting, COO Renewables for Innogy. “This demonstration project will give us a better understanding of how the cost can be driven down.
“The industrialised approach of the TetraSpar design, combined with innogy’s experience in delivering offshore wind projects, will enable large-scale, cost-effective deployment of floating wind projects around the world.”

Stiesdal’s TetraSpar floating foundation has a modular layout consisting of a tubular steel main structure with a suspended keel. It is expected to offer important competitive advantages over existing floating wind concepts, with the potential for leaner manufacturing, assembly and installation processes with lower material costs.

Dorine Bosman, VP Shell Wind Development, added: “This initiative could help to lower the cost of offshore wind energy while providing more options for development locations, giving access to higher wind speeds and deeper water depths. Building our offshore wind business is a key part of the Shell New Energies strategy. Investing in innovative projects such as TetraSpar gives us early access to a new technology that could help us become a leading player in this field.”

The partners hope to deploy the demonstration project in 2019. It will be located approximately 10km from shore in water depths of 200m at the test site of the Marine Energy Test Centre (Metcentre) near Stavanger in Norway. At site the floating structure will be moored to the seabed with three anchor lines and connected to the electrical grid.