1. SODAR: Uses and Acceptance Laura Tabor Wind Engineering Intern EAPC Wind Energy Services August 7, 2009

2. What is SODAR? A form of remote sensing (LIDAR also) SOnic Detection And Ranging Emits sound (pings) and measures Doppler shift and intensity of reflected signal Measures vertical and horizontal wind speed, direction, and turbulence Remote sensing devices are used increasingly in monitoring campaigns

3. Triton SODAR

4. Advantages of Remote Sensing Measure wind data above standard met tower heights (through hub and tip height) Measures the vertical component of the wind Avoids issues of tower shading Easy installation and portability Powered with two solar panels (7 W continuous power draw) Low visual impact May not require permits (remote or secluded sites)

5. Limitations of SODAR Measurements affected by precipitation Analysis of data from sites with complex terrain requires additional effort May underestimate wind resource, requiring calibration with anemometer data Remote sensing is not yet accepted by industry as stand alone solution for monitoring for large commercial projects

6. EAPC and SODAR Currently offering SODAR services Installed SODAR profiler on a site near the Adirondacks in July Now have two data monitoring devices at site: 60 m met tower and SODAR Have 18 months of met tower data Working to expand remote sensing services, possibly including LIDAR

7. Data Analysis: Goals Determine correlations between wind speeds and directions Compare predicted wind shear from met tower to measured SODAR values Compare turbulence measurements Bear in mind limitations of current site Low wind speed Complex terrain: forest and topography Only a little over a month of data

8. Early Results: Wind Speed Note: Raw SODAR data is from 60.0m, not 57.6m

9. Early Results: Wind Direction 57.6 m, 60.0 m50.0 m 40.0 m SODAR Top: SODAR, Bottom: Met tower

10. Early Results: Wind Speed Correlation Sector with most wind data shows good correlation

11. Early Results: Shear

13. Expanded Clearing: Turbulence Site has shown low wind resource Does expanded clearing around site improve quality? Compare data: 1 month before, 1 month after Decreased turbulence observed in some sectors

14. Conclusions and Next Steps Current Site: Correlations and shear data encouraging Plan to use correlation to predict 80m wind speeds more accurately Additional data should improve accuracy of wind resource assessment General: All indications are that remote sensing will see increased use and value. Improved uncertainty figures (P75, P90) and financial terms in future?