According to the latest news from NIRAS, offshore wind foundation design can be optimised to withstand the actual conditions even in areas with extreme weather. The company detailed on this after running simulations based on actual typhoons in Taiwan, saying that this approach can lead to a less conservative design and that extreme weather does not mean higher costs.
The Denmark-based consultancy, which opened its Taiwan office in May 2017 , said that even with new and popular methods such as Computational Fluid Dynamic (CFD) simulations, which NIRAS employs, using the right data in a simulation is vital and can affect not only the design, but also the costs.
Using regular waves and water levels for a simulation or using extreme weather such as typhoons makes a difference, NIRAS states, explaining that its recent experiences have highlighted that regular waves are not sufficient as a basis for designing the most optimal offshore wind turbine foundations, particularly in areas with nonlinear extreme waves, like those in Taiwan or Northern Europe.
In addition to the aforementioned, NIRAS pointed out that the observations often lack a consecutive time series of metocean parameters; coherent observations of wind, weather and climatic conditions in a particular location – parameters that are extremely relevant for optimal foundation design. Consecutive parameters are particularly very important for correct simulation, especially with regard to the differences in wind and weather in different parts of the world, the consultancy said.
“Taiwan is in the same situation as we were in Northern Europe 10 years ago. They have not used their seabed before and they lack data on wind and offshore – exactly the same situation as in Denmark a decade ago. Since then, however, we have accumulated a wealth of important data. That is why we run several actual typhoons through simulation to ensure we obtain the best data before designing the foundations for the wind turbines,” said Tony Erik Bergøe , senior specialist at NIRAS.
According to Bergøe, NIRAS will continue to use this simulation approach on future projects to increase and improve knowledge for the design of future wind turbines.