innogy, Shell and Stiesdal Offshore Technologies (SOT) have taken the final investment decision on the ‘TetraSpar’ floating foundation demonstration project which will be tested off the Norwegian coast in 2020. Its modular layout consists of a tubular steel main structure with a suspended keel.Shell has increased their share in the project from 33% to 66%. innogy retains 33% in the newly founded project company and SOT is contributing to the project with its modular TetraSpar concept and holds the remaining shares (1%). As technology partner, Siemens Gamesa Renewable Energy (SGRE) will provide the wind turbine and required services.
The components for the floating prototype will be manufactured by Welcon A/S in Give, Denmark. The components will be transported to the Port of Grenaa to be assembled. Following launch of the foundation, the wind turbine will be mounted on the foundation at the quayside using a land-based crane. From there, the foundation structure including the turbine will be towed to the test site in the northern part of the North Sea, moored to the seabed with three anchor lines and connected to the electrical grid. 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. The demonstration project will use a 3.6MW SGRE direct drive offshore wind turbine.