Precise knowledge of winds: a necessity for the ORE development
The definition and optimal design of ORE projects requires an accurate knowledge of atmospheric flow properties such as the spatial and temporal variability of wind at turbine mast height, its vertical shear, or the intensity and structure of turbulence. These parameters are used at several levels, in particular for:
- estimating the wind energy resource at a given site;
- optimizing electricity production and reducing turbine wear;
- estimating loadings on wind turbines including extreme loadings for system survivability in storm conditions and average loadings for fatigue design;
- offshore installation of ORE systems as well as operations and maintenance.
Generally speaking, wind conditions can be obtained through in-situ measurements at the site of interest, satellite observations, numerical simulations… However, regional and local effects are important, especially for coastal domains and continental seas where atmospheric conditions are strongly modified by the topography of the surrounding regions. France Energies Marines has been conducting R&D projects for several years, with the main players in the wind energy sector, on wind fields at different spatial scales. The Institute also studied the feasibility of developing an offshore research platform dedicated to offshore wind energy (FOWRCE SEA Project).
A multi-criteria approach for the selection of floating offshore wind sites
An Interreg project to assess the potential of the European Atlantic Area for the deployment of floating wind turbines was carried out from 2017 to 2022 (ARCWIND project). It produced a multi-criteria approach to the selection of wind farm locations, involving different technology developers. France Energies Marines contributed scientifically to this project through the improvement of the representation of storm sea states in the North-East Atlantic.
Precise wind characterisation to better evaluate the resource
France Energies Marines coordinated a collaborative project whose objective is to improve wind characterisation in order to reduce uncertainties in resource assessment and wind turbine design (CARAVELE project). This project focused on the joint exploitation of modelled wind fields and in-situ and satellite observations. The coupling effects between the ocean and the atmosphere through the effect of breaking waves on wind lifting over them were also studied. Experiments conducted in the University of Miami test tank improved the restitution of extreme winds for wind turbine design using satellite images. While the assessment of the wind resource is crucial, so is the formulation of recommendations for the design of machines. France Energies Marines has therefore initiated several collaborative projects : two on the deployment of wind and turbulence observation resources (POWSEIDOM and DRACCAR-NEMO projects), and one on the characterisation of extreme wind and waves during tropical cyclones (OROWSHI project).
A better understanding of the interactions between sea and atmosphere
Another collaborative project has been launched at the initiative of France Energies Marines to set up a dedicated digital chain capable of accurately simulating wind, wave and current conditions in the Gulf of Lion in the Mediterranean (CASSIOWPE project). This area will host three pilot farms and several commercial floating wind farms in the short and medium term. The project will focus on improving the capability of numerical models coupling the sea and the atmosphere to capture wind, wave and circulation conditions in the difficult and specific conditions of the Gulf of Lion. The numerical tools will be intensively validated using existing in-situ and satellite data. A database of metocean conditions in the Gulf of Lion will thus be proposed. This database will provide estimates of the wind resource and the aerodynamic and hydrodynamic constraints to be considered in the design of floating wind turbines.
The integration of climate change impacts
Over the lifespan of offshore wind farms which is more than 25 years, the wind resource, or in other words the wind distribution, might evolve leading to a modification of the associated energy production, impacting the business plan established during the creation of these farms. Climate change could also affect the length of the seasons or their intensity and therefore impact the balance between supply and demand in the energy sector. The intensity of extreme wind events as well as their frequency can also change and impact the design of the wind turbines as well as the foundations, moorings, substations, and export cables. Extreme wave and water level events are also to be considered because they are dimensioning for these systems. An first project (2C NOW project) has just been launched by the Institute on this subject.
Photo credit: Alba Fotos / Pixabay
Climate change impact on offshore wind
Characterising the atmosphere and sea surface interactions for the deployment of offshore wind in the Gulf of Lion
Deployment of wind and turbulence observations in the Mediterranean
Adaptation and implementation of floating wind energy conversion technology for the Atlantic Region
Wind characterisation for offshore renewable energies applications
DRACCAR – NEMO
New methods for turbulence measurements and models in offshore wind
Future offshore wind research center at sea
Assessment of the Mediterranean observational data system for targeted applications
Offshore wind turbine design including joint wind-wave information in standard for hurricane-exposed sites
Metocean Data Analysis Researcher