1 / 19

SAR for offshore wind energy

Explore the development of offshore wind farms, study wind resource variations, wind farm wake detection, and high-resolution wind resource mapping using SAR technology. Investigate the challenges and benefits of SAR observations for offshore wind energy assessments.

lrojas
Download Presentation

SAR for offshore wind energy

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. SAR for offshore wind energy Tobias Ahsbahs1, Charlotte Hasager1, Caroline Draxl2, Galen MacLaurin2, Alex Newcombe3, Nicolai G. Nygaard3, and Merete Badger1 1) Technical University of Denmark, Wind Energy Risø, Roskilde, Denmark 2) National Renewable Energy Laboratory, Golden, Colorado, USA 3) ØrstedWind Power, Fredericia, Denmark

  2. Outline • Offshore wind – some key numbers • Application examples SAR for wind energy • Wind resource variation • Wind farm wake detection

  3. Development of offshore wind farms in Europe Offshore wind is growing fast Larger wind farms New markets (US, Taiwan, China…)

  4. Where are offshore wind farms planned? www.4coffshore.com • Europe: • North Sea • Baltic Sea • Close to shore • USA: • East Coast • Close to shore

  5. What makes SAR wind fields attractive? • High spatial resolution • Large swath widths • Open data access via Copernicus

  6. SAR wind archive at DTU Wind Energy SAR winds available at: https://satwinds.windenergy.dtu.dk/ NRT processing of Sentinel-1 and archive of Envisat

  7. SAR for wind resource assessment Wind climatology (wind atlas) from SAR wind fields High accuracy needed: Long time series necessary Use multiple sensor (Envisat, Radarsat-1, Sentinel-1A, and B) Need to inter-calibrate for consistency (Badger et. al .(2019), in review)

  8. Mean wind speed maps US East Coast SAR WRF 25 designated areas WRF data from WIND Toolkit Draxl et.al. (2015) To be published: Ahsbahs et.al. (2019) • Meso-scale model WRF is available for planning of wind farm projects. • Satellite (SAR) and meso-scale model (WRF) based mean wind maps. • Gradients in the mean wind speed with the distance to shore. • More spatial variability in the mean wind speed from SAR.

  9. Variation of wind resources within each wind farm SAR To be published: Ahsbahs et.al. (2019) WRF • Extract mean wind speed within each potential wind farm area • Larger variation of wind resources from SAR than model • Hint towards underestimating spatial variability of wind resources?

  10. Wind turbine and farm wakes U(z) U(z) • What is the wind farm wake? • Energy extracted • Decreased wind speed • Increased turbulence • Wind farm wakes in SAR: • SAR observes the sea surface • Wakes at hub height • vertical extrapolation

  11. SAR wind fields in the presence of wind farm wakes English East Coast Wind farms Wakes visible Wind farms Wind direction

  12. Large scale reference data in the wake – the BEACon experiment Doppler radar wind measurements provided by Ørsted’s BEACon experiment • Two Doppler radars • Large scale measurements • Collocated SAR images

  13. Large scale reference data in the wake – the BEACon experiment SAR Doppler radar

  14. Large scale reference data in the wake – the BEACon experiment Velocity deficit characterizes reduced winds in the wake. Structure of the wake similar in SAR and Doppler radar. First comparison at full scale wind farm.

  15. Summary High resolution wind resource maps • Identify variation in wind resources • Compare with meso-scale model outputs Wind farm wakes offshore • Wakes are visible in SAR images • Structure of the wind farm wake can also be observed

  16. Challenges • SAR observation at the surface vs. atmospheric processes higher in the atmosphere. • Wind turbines operate up to 250m height • Limited sampling rate and sampling biases from SAR. • The interaction of wind farm wakes with the ocean surface needs to be better understood.

  17. Acknowledgements • Satellite SAR data from the ESA, Copernicus, and NOAA. • The SAR Ocean Products System (SAROPS) by the Johns Hopkins University, Applied Physics Laboratory and the US National Atmospheric and Oceanographic Administration (NOAA). • This work received funding from the EU H2020 program under grant agreement no. 730030 (CEASELESS project) • Access to Doppler radar wind observation from the BEACon experiment provided by Ørsted

  18. References Draxl, C., Clifton, A., Hodge, B., McCaa, J.: The Wind Integration National Dataset ( WIND ) Toolkit, Appl. Energy, 151(August), 355–366, doi:10.1016/j.apenergy.2015.03.121, 2015. Ahsbahs, T., Maclaurin, G., Draxl, C, Jackson, C., Monaldo, F., Badger, M.: US East Coast synthetic aperture radar wind atlas for offshore wind Energy, submitted to Wind Energy Science. Badger, M., Ahsbahs, T., Maule, P., Karagali, I. Inter-calibration of SAR data series for offshore wind resource assessment, Remote Sensing of Environment (in review), 2019

More Related