About the project

Ensuring more reliable analysis and testing methods through advancement of modelling and experimental techniques for bottom fixed offshore wind turbines. WAS XL (Wave loads and soil support for extra large monopiles) is a KPN-project funded by the Research Council of Norway.

Picture of a model of a wind turbine


Economies of scale are pushing for larger (6-12MW) offshore wind turbines (OWT), which require larger support structures. For shallow and intermediate water depths, large-diameter monopile foundations are considered most promising with respect to the levelized cost of energy.

However, the eigenfrequencies decrease – getting closer to the primary wave frequencies – as structure size increases, making the structure more susceptible to nonlinear wave loading, for which more accurate and validated analysis methods are needed. Also, the wave load history on the monopile has an impact on the soil response, which current design practices do not address properly.

Research partners:

Norwegian University of Science and Technology, NTNU
Norwegian Geotechnical Institute, NGI

Industry partners:

EDF Direction Recherche et Développement