Wind sensing with drone mounted wind lidars: proof of concept

Abstract. The fusion of drone and wind lidar technology introduces the exciting possibility of performing high-quality wind measurements virtually anywhere for substantially lower costs than established in-situ and remote sensing techniques. In this paper we will present a proof of concept (POC) drone-lidar system and report results from several test campaigns that demonstrate its ability to measure accurate wind speeds. The POC system is based on a dual-telescope Continuous Wave (CW) lidar, with drone-borne telescopes and ground-based opto-electronics. Commercially available drone and gimbal units are employed. The demonstration campaigns started with a series of comparisons of the wind speed measurements acquired by the POC system to simultaneous measurements performed by nearby mast based sensors. Generally very good agreement was found. Subsequently the extent of the flow disturbance caused by the drone downwash was investigated. These tests vindicated the somewhat conservative choice of lidar measurement range made for the initial wind speed comparisons. Overall, the excellent results obtained without any drone motion correction and with fairly primitive drone position control indicate the potential of drone-lidar systems in terms of accuracy and applications. The next steps in the development are outlined in the paper and several potential applications are discussed.

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Wind sensing with drone-mounted wind lidars: proof of concept

Atmospheric Measurement Techniques ◽

10.5194/amt-13-521-2020 ◽

2020 ◽

Vol 13 (2) ◽

pp. 521-536

Author(s):

Nikola Vasiljević ◽

Michael Harris ◽

Anders Tegtmeier Pedersen ◽

Gunhild Rolighed Thorsen ◽

Mark Pitter ◽

...

Keyword(s):

Wind Speed ◽

Continuous Wave ◽

Position Control ◽

Horizontal Wind ◽

Lidar Measurement ◽

Proof Of Concept ◽

Horizontal Wind Speed ◽

Wind Speeds ◽

Potential Applications ◽

Wind Measurements

Abstract. The fusion of drone and wind lidar technology introduces the exciting possibility of performing high-quality wind measurements virtually anywhere. We present a proof-of-concept (POC) drone–lidar system and report results from several test campaigns that demonstrate its ability to measure accurate wind speeds. The POC system is based on a dual-telescope continuous-wave (CW) lidar, with drone-borne telescopes and ground-based optoelectronics. Commercially available drone and gimbal units are employed. The demonstration campaigns started with a series of comparisons of the wind speed measurements acquired by the POC system to simultaneous measurements performed by nearby mast-based sensors. On average, an agreement down to about 0.1 m s−1 between mast- and drone-based measurements of the horizontal wind speed is found. Subsequently, the extent of the flow disturbance caused by the drone downwash was investigated. These tests vindicated the somewhat conservative choice of lidar measurement ranges made for the initial wind speed comparisons. Overall, the excellent results obtained without any drone motion correction and with fairly primitive drone position control indicate the potential of drone–lidar systems in terms of accuracy and applications. The next steps in the development are outlined and several potential applications are discussed.

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Coastal Wind Measurements Using a Single Scanning LiDAR

Remote Sensing ◽

10.3390/rs12081347 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1347 ◽

Cited By ~ 4

Author(s):

Susumu Shimada ◽

Jay Prakash Goit ◽

Teruo Ohsawa ◽

Tetsuya Kogaki ◽

Satoshi Nakamura

Keyword(s):

Wind Speed ◽

Goodness Of Fit ◽

Sonic Anemometer ◽

Data Availability ◽

Horizontal Wind ◽

Research Station ◽

Lidar Measurement ◽

Wind Speeds ◽

Wind Measurements ◽

Scanning Lidar

A wind measurement campaign using a single scanning light detection and ranging (LiDAR) device was conducted at the Hazaki Oceanographical Research Station (HORS) on the Hazaki coast of Japan to evaluate the performance of the device for coastal wind measurements. The scanning LiDAR was deployed on the landward end of the HORS pier. We compared the wind speed and direction data recorded by the scanning LiDAR to the observations obtained from a vertical profiling LiDAR installed at the opposite end of the pier, 400 m from the scanning LiDAR. The best practice for offshore wind measurements using a single scanning LiDAR was evaluated by comparing results from a total of nine experiments using several different scanning settings. A two-parameter velocity volume processing (VVP) method was employed to retrieve the horizontal wind speed and direction from the radial wind speed. Our experiment showed that, at the current offshore site with a negligibly small vertical wind speed component, the accuracy of the scanning LiDAR wind speeds and directions was sensitive to the azimuth angle setting, but not to the elevation angle setting. In addition to the validations for the 10-minute mean wind speeds and directions, the application of LiDARs for the measurement of the turbulence intensity (TI) was also discussed by comparing the results with observations obtained from a sonic anemometer, mounted at the seaward end of the HORS pier, 400 m from the scanning LiDAR. The standard deviation obtained from the scanning LiDAR measurement showed a greater fluctuation than that obtained from the sonic anemometer measurement. However, the difference between the scanning LiDAR and sonic measurements appeared to be within an acceptable range for the wind turbine design. We discuss the variations in data availability and accuracy based on an analysis of the carrier-to-noise ratio (CNR) distribution and the goodness of fit for curve fitting via the VVP method.

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Doppler wind lidar activities at Cabauw

10.5194/ems2021-136 ◽

2021 ◽

Author(s):

Steven Knoop ◽

Fred Bosveld ◽

Marijn de Haij ◽

Arnoud Apituley

Keyword(s):

Wind Speed ◽

Wind Profile ◽

Continuous Wave ◽

Wind Farms ◽

Data Availability ◽

Horizontal Wind ◽

Horizontal Wind Speed ◽

Low Clouds ◽

Wind Measurements ◽

Wind Lidar

Atmospheric motion and turbulence are essential parameters for weather and topics related to air quality. Therefore, wind profile measurements play an important role in atmospheric research and meteorology. One source of wind profile data are Doppler wind lidars, which are laser-based remote sensing instruments that measure wind speed and wind direction up to a few hundred meters or even a few kilometers. Commercial wind lidars use the laser wavelength of 1.5 &#181;m and therefore backscatter is mainly from aerosols while clear air backscatter is minimal, limiting the range to the boundary layer typically.We have carried out a two-year intercomparison of the ZephIR 300M (ZX Lidars) short-range wind lidar and tall mast wind measurements at Cabauw [1]. We have focused on the (height-dependent) data availability of the wind lidar under various meteorological conditions and the data quality through a comparison with in situ wind measurements at several levels in the 213m tall meteorological mast. We have found an overall availability of quality-controlled wind lidar data of 97% to 98 %, where the missing part is mainly due to precipitation events exceeding 1 mm/h or fog or low clouds below 100 m. The mean bias in the horizontal wind speed is within 0.1 m/s with a high correlation between the mast and wind lidar measurements, although under some specific conditions (very high wind speed, fog or low clouds) larger deviations are observed. This instrument is being deployed within North Sea wind farms.Recently, a scanning long-range wind lidar Windcube 200S (Leosphere/Vaisala) has been installed at Cabauw, as part of the Ruisdael Observatory program [2]. The scanning Doppler wind lidars will provide detailed measurements of the wind field, aerosols and clouds around the Cabauw site, in coordination with other instruments, such as the cloud radar.[1] Knoop, S., Bosveld, F. C., de Haij, M. J., and Apituley, A.: A 2-year intercomparison of continuous-wave focusing wind lidar and tall mast wind measurements at Cabauw, Atmos. Meas. Tech., 14, 2219&#8211;2235, 2021[2] https://ruisdael-observatory.nl/

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Dutch Offshore Wind Atlas Validation against Cabauw Meteomast Wind Measurements

Energies ◽

10.3390/en13246558 ◽

2020 ◽

Vol 13 (24) ◽

pp. 6558

Author(s):

Steven Knoop ◽

Pooja Ramakrishnan ◽

Ine Wijnant

Keyword(s):

Wind Speed ◽

Offshore Wind ◽

Weather Forecasts ◽

Wind Speeds ◽

Weather Model ◽

Significant Difference ◽

Wind Measurements ◽

Sea Wind ◽

Global Datasets ◽

Meteorological Institute

The Dutch Offshore Wind Atlas (DOWA) is validated against wind speed and direction measurements from the Cabauw meteorological mast for a 10-year period and at heights between 10 m and 200 m. The validation results are compared to the Royal Netherlands Meteorological Institute (KNMI) North Sea Wind (KNW) atlas. It is found that the average difference (bias) between DOWA wind speeds and those measured at Cabauw varies for the different heights between −0.1 m/s to 0.3 m/s. Significant differences between DOWA and KNW are only found at altitudes of 10 m and 20 m, where KNW performs better. For heights above 20 m, there is no significant difference between DOWA and KNW with respect to the 10-year averaged wind speed bias. The diurnal cycle is better captured by DOWA compared to KNW, and the hourly correlation is slightly improved. In addition, a comparison with the global European Center for Medium-Range Weather Forecasts (ECMWF) ERA-Interim and ERA5 reanalyses (used for KNW and DOWA, respectively) is made, highlighting the added skill provided by downscaling those global datasets with the weather model HARMONIE.

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accuracy of wind measurements on towers or stacks1,2

Bulletin of the American Meteorological Society ◽

10.1175/1520-0477-48.9.665 ◽

1967 ◽

Vol 48 (9) ◽

pp. 665-675 ◽

Cited By ~ 30

Author(s):

Gerald C. Gill ◽

Lars E. Olsson ◽

Josef Sela ◽

Motozo Suda

Keyword(s):

Wind Speed ◽

Scale Model ◽

Wind Speeds ◽

Lattice Type ◽

Free Air ◽

Scale Models ◽

The Face ◽

Wind Measurements ◽

Wind Tunnel Data ◽

Undisturbed Flow

Wind sensors mounted on towers and smokestacks do not always indicate the true free-air flow. To determine the probable errors in measurements of wind speed and direction around such structures, quarter-scale models have been tested in a large wind tunnel. Data on changes in wind speed and direction were obtained by using smoke, very small wind vanes, and a scale model propeller anemometer. Most emphasis has been placed on a relatively open lattice-type tower, but a solid tower and a stack were also studied. The analysis shows that in the wake of lattice-type towers disturbance is moderate to severe, and that in the wake of solid towers and stacks there is extreme turbulence, with reversal of flow. Recommendations for locating wind sensors in the wind field relative to the supporting structure are given for each of the three structures studied. Guidelines are suggested regarding probable errors in measurements of wind speed and direction around different supporting structures, as outlined below. For an open triangular tower with equal sides D, the wake is about 1-1/2D in width for a distance downwind of at least 6D. Sensors mounted 2 D out from the corner of such a tower will usually measure speeds within ± 10° of that of the undisturbed flow for an arc of about 330°. The disturbance by very dense towers and stacks is much greater. Wind sensors mounted 3 diameters out from the face of a stack will measure wind speeds within ± 10%, and directions within ± 10° of the undisturbed flow for an arc of about 180°.

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Intercomparison of middle-atmospheric wind in observations and models

Atmospheric Measurement Techniques ◽

10.5194/amt-11-1971-2018 ◽

2018 ◽

Vol 11 (4) ◽

pp. 1971-1987 ◽

Cited By ~ 12

Author(s):

Rolf Rüfenacht ◽

Gerd Baumgarten ◽

Jens Hildebrand ◽

Franziska Schranz ◽

Vivien Matthias ◽

...

Keyword(s):

Wind Profile ◽

Microwave Radiometer ◽

Horizontal Wind ◽

Random Errors ◽

Good Correspondence ◽

Mesopause Region ◽

Wind Speeds ◽

Wind Measurements ◽

Remote Sensing Techniques

Abstract. Wind profile information throughout the entire upper stratosphere and lower mesosphere (USLM) is important for the understanding of atmospheric dynamics but became available only recently, thanks to developments in remote sensing techniques and modelling approaches. However, as wind measurements from these altitudes are rare, such products have generally not yet been validated with (other) observations. This paper presents the first long-term intercomparison of wind observations in the USLM by co-located microwave radiometer and lidar instruments at Andenes, Norway (69.3∘ N, 16.0∘ E). Good correspondence has been found at all altitudes for both horizontal wind components for nighttime as well as daylight conditions. Biases are mostly within the random errors and do not exceed 5–10 m s−1, which is less than 10 % of the typically encountered wind speeds. Moreover, comparisons of the observations with the major reanalyses and models covering this altitude range are shown, in particular with the recently released ERA5, ECMWF's first reanalysis to cover the whole USLM region. The agreement between models and observations is very good in general, but temporally limited occurrences of pronounced discrepancies (up to 40 m s−1) exist. In the article's Appendix the possibility of obtaining nighttime wind information about the mesopause region by means of microwave radiometry is investigated.

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A two-year intercomparison of CW focusing wind lidar and tall mast wind measurements at Cabauw

10.5194/amt-2020-304 ◽

2020 ◽

Author(s):

Steven Knoop ◽

Fred C. Bosveld ◽

Marijn J. de Haij ◽

Arnoud Apituley

Keyword(s):

Wind Speed ◽

Wind Direction ◽

Continuous Wave ◽

Data Availability ◽

Horizontal Wind ◽

Horizontal Wind Speed ◽

Low Clouds ◽

Wind Measurements ◽

Wind Lidar ◽

The Mean

Abstract. A two-year measurement campaign of the ZephIR 300 vertical profiling continuous-wave (CW) focusing wind lidar has been carried out by the Royal Netherlands Meteorological Institute (KNMI) at the Cabauw site. We focus on the (height-dependent) data availability of the wind lidar under various meteorological conditions and the data quality through a comparison with in situ wind measurements at several levels in the 213-m tall meteorological mast. We find an overall availability of quality controlled wind lidar data of 97 % to 98 %, where the missing part is mainly due to precipitation events exceeding 1 mm/h or fog or low clouds below 100 m. The mean bias in the horizontal wind speed is within 0.1 m/s with a high correlation between the mast and wind lidar measurements, although under some specific conditions (very high wind speed, fog or low clouds) larger deviations are observed. The mean bias in the wind direction is within 2°, which is on the same order as the combined uncertainty in the alignment of the wind lidars and the mast wind vanes. The well-known 180° error in the wind direction output for this type of instrument occurs about 9 % of the time. A correction scheme based on data of an auxiliary wind vane at a height of 10 m is applied, leading to a reduction of the 180° error below 2 %. This scheme can be applied in real-time applications in case a nearby, freely exposed, mast with wind direction measurements at a single height is available.

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A 2-year intercomparison of continuous-wave focusing wind lidar and tall mast wind measurements at Cabauw

Atmospheric Measurement Techniques ◽

10.5194/amt-14-2219-2021 ◽

2021 ◽

Vol 14 (3) ◽

pp. 2219-2235

Author(s):

Steven Knoop ◽

Fred C. Bosveld ◽

Marijn J. de Haij ◽

Arnoud Apituley

Keyword(s):

Wind Speed ◽

Wind Direction ◽

Continuous Wave ◽

Data Availability ◽

Horizontal Wind ◽

Horizontal Wind Speed ◽

Low Clouds ◽

Wind Measurements ◽

Wind Lidar ◽

The Mean

Abstract. A 2-year measurement campaign of the ZephIR 300 vertical profiling continuous-wave (CW) focusing wind lidar has been carried out by the Royal Netherlands Meteorological Institute (KNMI) at the Cabauw site. We focus on the (height-dependent) data availability of the wind lidar under various meteorological conditions and the data quality through a comparison with in situ wind measurements at several levels in the 213 m tall meteorological mast. We find an overall availability of quality-controlled wind lidar data of 97 % to 98 %, where the missing part is mainly due to precipitation events exceeding 1 mm h−1 or fog or low clouds below 100 m. The mean bias in the horizontal wind speed is within 0.1 m s−1 with a high correlation between the mast and wind lidar measurements, although under some specific conditions (very high wind speed, fog or low clouds) larger deviations are observed. The mean bias in the wind direction is within 2∘, which is of the same order as the combined uncertainty in the alignment of the wind lidars and the mast wind vanes. The well-known 180∘ error in the wind direction output for this type of instrument occurs about 9 % of the time. A correction scheme based on data of an auxiliary wind vane at a height of 10 m is applied, leading to a reduction of the 180∘ error below 2 %. This scheme can be applied in real-time applications in the situation that a nearby freely exposed mast with wind direction measurements at a single height is available.

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Analysis of the Wind Turbine Selection for the Given Wind Conditions

Energies ◽

10.3390/en14227740 ◽

2021 ◽

Vol 14 (22) ◽

pp. 7740

Author(s):

Waldemar Kuczyński ◽

Katarzyna Wolniewicz ◽

Henryk Charun

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

Wind Turbines ◽

Wind Farm ◽

Medium Size ◽

Wind Speeds ◽

The North ◽

Wind Measurements ◽

Hourly Distribution ◽

The Given

The aim of the current paper is to present an approach to a wind turbine selection based on an annual wind measurements. The proposed approach led to a choice of an optimal device for the given wind conditions. The research was conducted for two potential wind farm locations, situated on the north of Poland. The wind measurements pointed out a suitability of the considered localizations for a wind farm development. Six types of wind turbines were investigated in each localization. The power of the wind turbines were in the range of 2.0 to 2.5 MW and with a medium size of the rotor being in the range of 82 to 100 m. The purpose of the research was to indicate a wind turbine with the lowest sensitivity to the variation of wind speed and simultaneously being most effective energetically. The Weibull density distribution was used in the analyses for three values of a shape coefficients k. The energy efficiency of the considered turbines were also assessed. In terms of the hourly distribution of the particular wind speeds, the most effective wind turbines were those with a nominal power of 2 MW, whereas the least effective were those with the nominal power of 2.3–2.5 MW. The novelty of the proposed approach is to analyze the productivity for many types of wind turbines in order to select the one which is the most effective energy producer. The analyses conducted in the paper allowed to indicate a wind turbine which generates the highest amount of energy independently on the wind speed variation.

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Validation of middle-atmospheric wind in observations and models

10.5194/amt-2017-390 ◽

2017 ◽

Author(s):

Rolf Rüfenacht ◽

Gerd Baumgarten ◽

Jens Hildebrand ◽

Franziska Schranz ◽

Vivien Matthias ◽

...

Keyword(s):

Wind Profile ◽

Microwave Radiometer ◽

Horizontal Wind ◽

Random Errors ◽

Good Correspondence ◽

Mesopause Region ◽

Wind Speeds ◽

Wind Measurements ◽

Remote Sensing Techniques

Abstract. Wind profile information throughout the upper stratosphere and lower mesosphere (USLM) is important for the understanding of atmospheric dynamics but became available only recently, thanks to developments in remote sensing techniques and modelling approaches. However, as wind measurements from these altitudes are still very rare, such products have generally not yet been validated with (other) observations. This paper presents the first long-term intercomparison of wind observations in the USLM by opposing co-located microwave radiometer and lidar instruments at Andenes (69.3° N, 16.0° E). Good correspondence has been found at all altitudes for both horizontal wind components for nighttime as well as daylight conditions. Biases are mostly within the random errors and do not exceed 5–10 m/s which is less than 10 % of the typically encountered wind speeds. Moreover, comparisons of the observations with the major re-analyses and models covering this altitude range are shown, especially also with the freshly released ERA5, ECMWF's first re-analysis to cover the whole USLM region. The agreement between models and observations is very good in general, but temporally limited occurrences of pronounced discrepancies (up to 40 m/s) exist. In the article's appendix the possibility of obtaining nighttime wind information about the mesopause region by means of microwave radiometry is investigated.

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