In the North Sea, an array of wind profiling wind lidars were deployed mainly on offshore platforms. The purpose was to observe free stream winds at hub height. Eight lidars were validated prior to offshore deployment with observations from cup anemometers at 60, 80, 100 and 116 m on an onshore met mast situated in flat terrain. The so-called “NORSEWInD standard” for comparing lidar and mast wind data includes the criteria that the slope of the linear regression should lie within 0.98 and 1.01 and the linear correlation coefficient higher than 0.98 for the wind speed range 4–16 m？s ？1. Five lidars performed excellently, two slightly failed the first criterion and one failed both. The lidars were operated offshore from six months to more than two years and observed in total 107 months of 10-min mean wind profile observations. Four lidars were re-evaluated post deployment with excellent results. The flow distortion around platforms was examined using wind tunnel experiments and computational fluid dynamics and it was found that at 100？m height wind observations by the lidars were not significantly influenced by flow distortion. Observations of the vertical wind profile shear exponent at hub height are？presented.
References
[1]
Wagner, R.; Antoniou, I.; Pedersen, S.M.; Courtney, M.S.; J？rgensen, H.E. The influence of the wind speed profile on wind turbine performance measurements. Wind Energy 2009, 12, 348–362.
[2]
Pe？a, A.; Hasager, C.B.; Gryning, S.; Courtney, M.; Antoniou, I.; Mikkelsen, T. Offshore wind profiling using Light Detection and Ranging Measurements. Wind Energy 2009, 12, 105–124.
[3]
Hahmann, A.N.; Lange, J.; Pe？a, A.; Hasager, C.B. The NORSEWInD Numerical Wind Atlas for the South Baltic. DTU Wind Energy E-0011 (EN);; DTU Wind Energy: Roskilde, Denmark, 2012; p. 53.
[4]
Smith, D.A.; Harris, M.; Coffey, A.S.; Mikkelsen, T.; Jorgensen, H.E.; Mann, J.; Danielian, G. Wind lidar evaluation at the danish wind test site in hovsore. Wind Energy 2006, 9, 87–93.
[5]
Kindler, D.; Oldroyd, A.; Macaskill, A.; Finch, D. An eight month test campaign of the Qinetiq ZephIR system: Preliminary results. Meteorol. Z 2007, 16, 479–489.
[6]
Antoniou, I.; J？rgensen, H.E.; Mikkelsen, T.; Frandsen, S.; Barthelmie, R.; Perstrup, C.; Hurtig, M. Offshore Wind Profile Measurements from Remote Sensing Instruments. Proceedings of the European Wind Energy Association Conference & Exhibition in Athens, Athens, Greece, 27 February–3 March 2006.
[7]
NORSEWInD. Available online: http://www.norsewind.eu (accessed on 3 September 2013).
[8]
Pe？a, A.; Mikkelsen, T.; Gryning, S.-E.; Hasager, C.B.; Hahmann, A.; Badger, M.; Karagali, I.; Courtney, M. Offshore Vertical Wind Shear: Final Report on NORSEWInD’s Work Task 3.1. DTU Wind Energy-E-Report-0005(EN);; DTU Wind Energy: Roskilde, Denmark, 2012; p. 116.
[9]
Stickland, M.; Scanlon, T.; Fabre, S.; Oldroyd, A.; Mikkelsen, T. Measurement and simulation of the flow field around a triangular lattice meteorological mast. J. Energy Power Eng. 2013. submitted.
[10]
Badger, M.; Badger, J.; Nielsen, M.; Hasager, C.B.; Pe？a, A. Wind class sampling of satellite SAR imagery for offshore wind resource mapping. J. Appl. Meteorol. Climatol 2010, 49, 2474–2491.
[11]
Berge, E.; Hasager, C.B.; Bredesen, R.E.; Hahmann, A.; Byrkjedal, O.; Pe？a, A.; Kravik, R.; Harstveit, K.; Costa, P.; Oldroyd, A. NORSEWIND—Mesoscale Model Derived Wind Atlases for the Irish Sea, the North Sea and the Baltic Sea. European Wind Energy Association Confernce, Vienna, Austria, 4–7 February 2013; pp. 1–6.
[12]
Hasager, C.B.; Badger, M.; Pe？a, A.; Larsen, X.G.; Bingol, F. SAR-Based wind resource statistics in the Baltic Sea. Remote Sens 2011, 3, 117–144.
[13]
Karagali, I.; Hoyer, J.; Hasager, C. SST diurnal variability in the North Sea and the Baltic Sea. Remote Sens. Environ 2012, 121, 159–170.
[14]
Karagali, I.; Pe？a, A.; Badger, M.; Hasager, C. Wind characteristics in the North and Baltic Seas from the QuikSCAT satellite. Wind Energy 2012, doi:10.1002/we.1565.
[15]
Karagali, I.; Badger, M.; Hahmann, A.; Pe？a, A.; Hasager, C.; Sempreviva, A.M. Spatial and temporal variability in winds in the Northern European Seas. Renew. Energy 2013, 57, 200–210.
[16]
ZephIR？. Available online: http://www.zephirlidar.com (accessed on 3 September 2013).
[17]
Pitter, M.; Slinger, C.; Harris, M. Introduction of Continous-Wave Doppler Lidar. In Remote Sensing for Wind Energy; Pe？a, A., Hasager, C.B., Lange, J., Anger, J., Badger, M., Bing？l, F., Bischoff, O., Cariou, J.-P., Dunne, F., Emeis, S., et al, Eds.;. DTU Wind Energy-E-Report-0029(EN); DTU Wind Energy: Roskilde, Denmark, 2013; pp. 72–103.
[18]
WindCube？. Available online: http://www.leosphere.com (accessed on 3 September 2013).
[19]
Cariou, J.-P. Pulsed Lidars. In Remote Sensing for Wind Energy; Pe？a, A., Hasager, C.B., Lange, J., Anger, J., Badger, M., Bing？l, F., Bischoff, O., Cariou, J.-P., Dunne, F., Emeis, S., et al, Eds.;. DTU Wind Energy-E-Report-0029(EN); DTU Wind Energy: Roskilde, Denmark, 2013; pp. 104–121.
[20]
Sonnenschein, C.M.; Horrigan, F.A. Signal-to-Noise relationships for Coaxial Systems that heterodyne backscatter from atmosphere. Appl. Opt 1971, 10, 1600–1604.
[21]
Menter, F.R.; Kuntz, M.; Langtry, R. Ten Years of Industrial Experience with the SST Turbulence Model. In Turbulence, Heat and Mass Transfer 4; Hanjalic, K., Nagano, Y., Tummers, M., Eds.; Begell House Inc.: New York, NY, USA, 2003; pp. 625–632.
[22]
Courtney, M.; Wagner, R.; Lindel？w, P. Testing and comparison of Lidars for profile and turbulence measurements in wind energy. IOP Conf. Ser.: Earth Environ. Sci 2008, 1, 012021, doi:10.1088/1755-1315/1/1/012021.
[23]
Stickland, M.; Scanlon, T.; Fabre, S. Computational and Experimental Study on the Effect of Flow Field Distortion on the Accuracy of the Measurements made by Anemometers on the Fino3 Meteorological Mast. Proceedings of EWEA Offshore: Moving Ahead of the Energy Curve, Amsterdam, The Netherlands, 29 November–1 December 2011.
[24]
Bing？l, F.; Mann, J.; Foussekis, D. Conically scanning lidar error in complex terrain. Meteorol. Z 2009, 18, 189–195.
[25]
Bing？l, F.; Mann, J.; Foussekis, D. Lidar error estimation with WAsP engineering. IOP Conf. Ser.: Earth Environ. Sci 2008, 1, 012058, doi:10.1088/1755-1307/1/1/012058.
[26]
Bradley, S.; Mikkelsen, T. LIDAR remote sensing. Int. Sustain. Energy Rev 2011, 5, 2–7.
[27]
Bradley, S.; Perrott, Y.; Behrens, P.; Oldroyd, A. Corrections for wind-speed errors from sodar and lidar in complex terrain. Bound. Layer Meteorol 2012, 143, 37–48.
[28]
Mann, J.; Ott, S.; J？rgensen, B.H.; Frank, H.P. WAsP Engineering 2000. Technical Report Ris？-R-1356(EN);; Ris？ National Laboratory for Sustainable Energy, Technical University of Denmark: Roskilde, Denmark, 2002; Volume R–1356(EN), p. 101.
[29]
Mortensen, N.G.; Heathfield, D.N.; Myllerup, L.; Landberg, L.; Rathmann, O. Getting Started with WAsP 9. Report Ris？-I-2571(EN);; Ris？ National Laboratory for Sustainable Energy, Technical University of Denmark: Roskilde, Denmark, 2007; p. 72.
[30]
Pe？a, A.; Hahmann, A.; Hasager, C.B.; Bing？l, F.; Karagali, I.; Badger, J.; Badger, M.; Clausen, N. South Baltic Wind Atlas. Report Ris？-R-1775(EN);; Ris？ National Laboratory for Sustainable Energy, Technical University of Denmark: Roskilde, Denmark, 2011; p. 66.
[31]
Draxl, C.; Hahmann, A.N.; Pe？a, A.; Giebel, G. Evaluating winds and vertical wind shear from weather research and forecasting model forecasts using seven planetary boundary layer schemes. Wind Energy 2012, doi:10.1002/we.1555.
[32]
Emeis, S. Wind Energy Meteorology—Atmospheric Physics for Wind Power Generation. In Series: Green Energy and Technology; Springer: Heidelberg, Germany, 2012; pp. 14–196.
[33]
Ca？adillas, B.; Neumann, T.; Raasch, S. Getting a Better Understanding of the Offshore Marine Boundary Layer: Comparison between Large Eddy Simulation and Offshore Measurement Data with Focus on Wind Energy Application. Proceedings of the Fifth International Symposium on Computational Wind Engineering (CWE2010), Chapel Hill, NC, USA, 23–27 May 2010.
[34]
Zoumakis, N.M. The dependence of the power-law exponent on surface roughness and stability in a neutrally and stably stratified surface boundary layer. Atmósfera 1993, 6, 79–83.
[35]
Westerhellweg, A.; Ca？adillas, B.; Beeken, A.; Neumann, T. One Year of Lidar Measurements at FINO1-Platform: Comparison and Verification to Met-Mast Data. Proceedings of 10th German Wind Energy Conference DEWEK 2010, Bremen, Germany, 17–18 November 2010.
[36]
Mu？oz-Esparza, D.; Canadillas, B.; Neumann, T.; van Beeck, J. Turbulent fluxes, stability and shear in the offshore environment: Mesoscale modelling and field observations at FINO1. J. Renew. Sustain. Energy 2012, 4, 063136:1–063136:16.
[37]
Lang, S.; McKeogh, E. LIDAR and SODAR measurements of wind speed and direction in upland terrain for wind energy purposes. Remote Sens 2011, 3, 1871–1901.
[38]
Takeyama, Y.; Ohsawa, T.; Yamashita, T.; Kozai, K.; Muto, Y.; Baba, Y.; Kawaguchi, K. Estimation of offshore wind resources in coastal waters off Shirahama using ENVISAT ASAR images. Remote Sens 2013, 5, 283–2897.
[39]
Takeyama, Y.; Ohsawa, T.; Kozai, K.; Hasager, C.B.; Badger, M. Effectiveness of WRF wind direction for retrieving coastal sea surface wind from synthetic aperture radar. Wind Energy 2012, doi:10.1002/we.1526.
