German Federal Ministry of Economic Affairs and Energy (BMWi) is funding a new research project launched by Ramboll, Fraunhofer IWES and Leibnitz University Hannover to reduce the levelised cost of energy (LCoE) by improving the design of large monopiles.
The TANDEM project (Towards an Advanced Design of Large Monopiles) aims to reduce design risks and cost of offshore wind turbine foundations.
Over a period of three years, the project partners will be revisiting hydrodynamic and geotechnical approaches with the scope to further improve current design methodologies for large diameter monopiles.
Refraction of waves has a significant effect on the hydrodynamic loading when the size of the foundation structure increases. Extensive numerical investigations are planned within the scope of TANDEM in order to better understand the hydrodynamic loads on large diameter monopiles and to reduce conservatism in current state-of-the-art approaches, Ramboll said.
The second scope of TANDEM is to improve the modelling of soil structure interaction under consideration of the large diameter of the piles and novel installation techniques. Measurements at different wind farms indicate that current approaches underestimate the foundation stiffness, according to Ramboll. In order to mitigate this, a number of pile tests will be performed in the Hannover Test Center for Support Structures (TTH) accompanied by extensive numerical modelling.