Growth through Research, development & demonstration in Offshore Wind

Wrapped composite joint for jacket foundations for offshore wind

Due to lighter structures and shorter manufacturing time wrapped joints can significantly reduce cost. Current joints are welded, which is a labour-intensive process.

Currently, monopiles are cheaper than jackets due to the complex welds that are needed. Composite joints can replace all the complex welding in jacket structures allowing for an increase in fatigue resistance. By applying composite joints, the amount of steel in a jacket is reduced by 40% to 60% compared to a welded jacket. In addition, the production time of the jacket is considerably shortened due to the possibility of prefabrication. Compared to monopiles, jackets manufactured with wrapped composite joints offer a potential cost reduction of 25% to 50% for the supporting structures. By applying the innovative joint, the carbon footprint of the turbine foundations will be reduced by 30% to 70%.

In the project WrapNode-I, GROW partners TU Delft and Shell and associate partners Smulders, HSM Offshore, Enersea, Siemens Gamesa, Tree Composites, BuFA, AOC and Sazlgitter will carry out full-scale and multi-axial tests of the wrapped joints and execute a performance validation. When successful a scaled jacket will be tested onshore in a follow-up WrapNode-II project. Finally, the technology will be demonstrated in an offshore campaign. This is needed to realize future commercial implementation and to demonstrate that the wrapped composite joint is a technically superior and cost-effective solution.

At the beginning of May 2021, the Netherlands Enterprise Agency (RVO) had decided to support the WrapNode-I project.

Jacket with composite joints
Jacket with composite joints
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Test composite joints
Test composite joints
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