Scour researchers from Ghent University, Leibniz University Hannover and the University of Porto teamed up with IMDC nv and the Department of Mobility and Public Works (Belgium) to start work on a collaborative project at HR Wallingford’s Fast Flow Facility (FFF) as part of PROTEUS, an EU-funded Hydralab+ project. The research project aims to improve the design of scour protection around offshore wind-turbine monopiles as well as future-proofing them against the impacts of climate change.
PROTEUS, which stands for the ‘PRotection of Offshore wind Turbine monopilEs against Scouring,’ will facilitate a series of large-scale experiments over a seven-week period in the FFF flume at HR Wallingford’s UK physical-modelling facilities.
“Research into scale effects requires large-scale model tests. The Fast Flow Facility, which is 75-m long x 8-m wide and contains a 1-m-deep sediment pit, is one of the world’s largest marine test facilities, and as such is ideal for carrying out this large-scale testing,” said David Todd, business development manager for research and commercialization at HR Wallingford. “The flume has been specially equipped for scour studies and has been designed to be able to generate a unique combination of waves and strong currents which are key to accurately testing scour protection.”
Although recent improvements to infrastructure and higher-voltage cables mean that offshore wind energy is now cheaper than new nuclear power, further cost savings can be achieved, according to HR Wallingford.
“Foundation costs represent 20% of the total costs in the case of a monopile, of which a significant proportion is related to the foundation’s scour protection,” said Peter Troch, head of the Civil Engineering Department of Ghent University and coordinator of the PROTEUS project. “This makes it vital to improve and reduce the cost of monopile scour-protection design.”
Lifetime extension is another promising route to reducing the costs of offshore wind turbines, so examining the foundation and behavior of the scour protection around the monopile is another element of this research project.
“We also need to consider the influence of climate change, which will increase the design storm conditions and influence the scour-protection stability,” Troch said. “Therefore, research towards a risk-based design will help to evaluate how well scour protection which is already installed performs and improve the design of future scour protection adapted to climate change.”
Hydralab+, which is funded by the EU’s Horizon 2020 Research and Innovation Programme, brings together facilities and researchers in experimental hydraulic and hydrodynamics.
Partners involved in PROTEUS include the following: Department of Civil Engineering at Ghent University, HR Wallingford (UK), the Ludwig-Franzius Institute for Hydraulic, Estuarine and Coastal Engineering at the University of Hannover, the Faculty of Engineering at the University of Porto, the Geotechnics division of the Belgian Department of Mobility and Public Works, and International Marine and Dredging Consultants (IMDC nv).