This same design will be put to the test from 21 May in an offshore testing campaign. The suction bucket jacket is a crucial element of future generations of offshore wind-turbine foundations; this design is intended to reduce the cost price by 40%, as a result of mass production.
In the design phase, Ib Andresen Industri provided active feedback by contributing its knowledge of steel and steel-processing.
Arne Kryger, R&D Manager, Ib Andresen Industri, put it this way: “Our knowledge of steel enabled us to significantly reduce the thickness of the material, reducing the weight of the suction bucket jacket from 140 tonnes to only 100 tonnes.
“Also, our in-house processes helped make this suction bucket jacket solution more cost-effective because we can cut sheets directly from coils. This minimises material wastage and provides a more precise production process which enables us to bolt the sections together, minimising the need for welding.” Ib Andresen Industri’s Steel Service Center has the capability to cut steel plates directly from coils.
Kristian A. Jacobsen, Head of Business Development, Universal Foundation, states that “we are proud to be able to take this type of industrially manufactured bucket jacket foundation to an offshore location and prove we can install it, with its bolted steel-plate joints and other features. The project is a brilliant example of close cooperation on an industrial project that exploits individual areas of expertise to reduce costs in the wind industry.”
About the suction bucket jacket solution
The test structure is 8 metres in diameter and the bottom section, made up of Ib Andresen Industri’s steel shells, is 8 metres tall.
For installation, the structure is lowered to the sea floor where Universal Foundation controls the advanced electric pump systems that create a vacuum to cause the structure to sink into the seabed. Once this installation procedure has been completed, the wind turbine’s cables and tower can be installed right away. Decommissioning the foundation is straightforward; the whole structure can be pushed up from the seabed by reversing the process, i.e. by pumping water into, rather than out of, the structure.
The project was supported by funding from the Energy Technology Development and Demonstration Programme (EUDP). “This is a brilliant example of how the EUDP subsidy works and makes a difference,” says Finn Daugaard Madsen, Project Manager, Siemens Gamesa.
“We build a knowledge bridge, we cooperate across disciplines and sectors, we develop, test and demonstrate and together we create new innovation that makes a difference. Without EUDP funding, it would be much more difficult for the manufacturing industry to carry out projects like this.”