NEMO: New methods for turbulence measurements and models in offshore wind

At a glance

• Precise knowledge of the prevailing wind conditions at the site is essential for the design of wind turbines and planning of wind farms. However, there are still knowledge gaps, particularly where turbulence is concerned.
• In the NEMO project, the partners are developing new experimental and numerical methods with the aim of closing these gaps and enabling wind farm developers and operators as well as wind turbine manufacturers to improve their assessment of turbulence.
• Fraunhofer IWES is focusing among other things on the further development of measuring methods with dual Doppler scanning lidar technology.

The challenge

The expansion of the offshore wind energy sector is a key element in achieving climate neutrality. The assessment of the site quality is of great importance in order to ensure the ambitious expansion of wind farms at sea – and thus also the expected electricity generation. It is not merely a matter of knowing the average wind speed, which is relatively easy to calculate. Turbulence, which is caused by the atmospheric system on the one hand, but also by interactions between wind turbines, wind farms, and wind farm clusters, is far more complex to understand but no less important. This turbulence has a tremendous impact on electricity production and the turbines’ lifetimes. The better it is understood, the more precisely the design of the turbines and farms can be optimized. However, there are still knowledge gaps, both where the measurements and the simulation of turbulence phenomena are concerned.

The solution

This is where the ICON project NEMO comes in. The project partners are establishing the scientific basis for the further improvement of standard site assessment methods for the offshore wind industry. To this end, they are developing a comprehensive measuring and modeling approach enabling the characterization of wind conditions on all relevant scales. In addition, a new measuring concept should also enable the combination of floating and dual Doppler scanning lidar technology. Large eddy simulations (LES) will also be used for the modeling of turbulence metrics.

Fraunhofer IWES is contributing its experience in the field of atmospheric physics and its expertise in the offshore wind industry to the NEMO project. In the further development of measuring methods and modeling, Fraunhofer IWES is focusing primarily on dual Doppler scanning lidar technology and the mesoscale modeling of wind conditions. 

The added value

NEMO’s results will provide a better understanding of the physics of the atmosphere and enable an appropriate and therefore feasible method for the wind industry to characterize turbulence in offshore wind farms. NEMO will provide wind farm developers and operators as well as wind turbine manufacturers with methods for improved site assessment that will improve the lifetime, reliability, and performance of wind farms and ultimately enable more profitable wind projects and lower investment costs thanks to optimized designs.