innogy SE, Shell and Stiesdal Offshore Technologies A/S (SOT) are bringing floating wind to the next level: The partners 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. 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. The project has a budget of €18 million.
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 partners will be part of a project team that will gain detailed, practical insights into the construction, installation and operation of the TetraSpar concept as well as detailed performance data.
Dynamic stability tests on a true-to-scale model have been running since last December, using the wave-wind channel at the University of Maine, USA, and the wave tank at FORCE in Lyngby, Denmark. This year, the components for the large 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.
