Leading companies active in the offshore wind market have come together to address installation challenges for very large or ‘XXL’ monopile foundations
The partners in the SIMOX (Sustainable Installation of XXL Monopiles) project want to develop innovative installation techniques for large wind turbines in the next five years.
Together, they want to test multiple techniques that can be used to install and decommission XXL monopiles for very large offshore wind turbines in a sustainable, cost-effective, societally and environmentally acceptable manner.
The project is being supported by the Netherlands Enterprise Agency. The companies involved are contributing €2.0M (US$2.4M) and the Dutch Government €4M.
Currently, the primary technique used to install monopiles is hydraulic impact piling (hammering), but this generates underwater noise that can be harmful to marine fauna and may ultimately be unsuitable for XXL monopiles.
Alternative installation technologies are being researched, developed, and tested and are at various technology readiness levels (TRLs). However, none has reached a TRL that makes it a preferred/ready solution for the installation of XXL monopiles, which have diameters ranging from 7.5 m to 11 m and weigh 1,000 to 2,400 tonnes.
In the SIMOX project, the companies involved will test alternatives including vibratory driving; gentle driving of piles; and so-called Blue Piling.
The project will assess the ‘driveability’ of the different solutions. Apart from driveability, the partners in the project will also assess their environmental aspects, with a focus on underwater noise, and the effect of the bearing capacity of the soil on the process. Implications for decommissioning will also be assessed.
The three-year SIMOX project is part of the GROW programme and is led by Professor Andrei Metrikine at Delft University of Technology.
Offshore contractors Van Oord, Boskalis and Seaway7 will lead onshore and nearshore tests, supported by the DOT (Delft Offshore Turbine).
Equipment manufacturers including Sif, IHC IQIP, CAPE Holland and GBM Works will provide monopiles and installation technology.
Operational aspects will be monitored and assessed by developers and turbine manufacturers including Shell, RWE and Siemens Gamesa Renewable Energy. Deltares and TNO will take an active part in the research and test campaign.
GROW director David de Jager said, “SIMOX is unique in its comprehensive approach to understanding and assessing multiple technologies under controlled conditions. Tests with scaled monopiles will be performed in laboratories, at two onshore sites and at a nearshore site.”