LIVERMORE
9/13/1996 through 9/20/1998
LOCATION DETAILS 
Latitude: 
N 40.90833° 
Longitude: 
W 105.23333° 
Township: 
11 N 
Range: 
70 W 
Section: 
21 
Elevation (ft.): 
7,037 
DATA DETAILS
April 30, 1996 through April 30, 1998:
This site was part of the Utility Wind Resource Assessment Program (UWRAP). Data provided by the Utility Wind Interest Group in cooperation with AWS
Truewind, National Renewable Energy Laboratory, Electrotek Concepts, and Xcel Energy  Public Service Company of Colorado. .
The collected data includes the following data fields:
 Wind speed, standard deviation of the wind speed, and data quality flag for an anemometer at 10m height and facing NW
 Wind speed, standard deviation of the wind speed, and data quality flag for an anemometer at 25m height and facing NW
 Wind speed, standard deviation of the wind speed, and data quality flag for an anemometer at 40m height
 Wind direction, standard deviation of the wind direction, and data quality flag for a wind vane at 25m height
 Wind direction, standard deviation of the wind direction, and data quality flag for a wind vane at 40m height
 Temperature from a sensor mounted at a height of 4m
Wind speed data at 40 meters represent a combination of data from primary and redundant sensors.
Only a text data file is available from this site. You can find this file here.
The file includes suspect data and when that data occurs, the value is generally a negative number. There is also a flag filed that indicates these suspect data values. For a version of this wind data with blanks rather than negative numbers, you can download here.
CSU was chosen as the contractor for the program on September 14, 2007. Using the raw data from all data plugs for this site, an analysis of the wind resource report was developed using Windographer 1.21. No data quality analysis was performed for this data other than what was available from the flag data fields included in the data. The suspect data was first removed from the collected data. Windographer was then used to add in synthetic data to these intervals with suspect data. The Windographer files (with blanks for the suspect data and with the blanks filled with synthetic data) are given below:
Highlights of the wind resource analysis at this site are shown below:
Data Properties 
Data Set Starts: 
9/13/1996 00:00 
Data Set Ends: 
9/20/1998 00:00 
Data Set Duration: 
24 months 
Length of Time Step: 
60 minutes 
Elevation (ft.): 
7,037 
Mean air density (kg/m³): 
0.973 
Wind Power Coefficients 
Power Density at 50m: 
464 W/m² 
Wind Power Class: 
4 (Good) 
Wind Shear Coefficients 
Power Law Exponent: 
0.0521 
Surface Roughness: 
0.000 m 
Roughness Class: 
0.59 
Roughness Description: 
Smooth 
Variable 
WS40 
WS25SW 
WS10SW 
Height above ground 
40 m (131 ft) 
25 m (82 ft) 
10 m (33 ft) 
Mean wind speed (mph) 
16.02 
15.51 
14.88 
Median wind speed (mph) 
13.66 
13.22 
12.54 
Min wind speed (mph) 
0 
0 
0 
Max wind speed (mph) 
64.96 
64.74 
63.84 
Mean power density (W/m²) 
455 
420 
381 
Mean energy content (kWh/m²/yr) 
3,986 
3,681 
3,336 
Energy pattern factor 
2.51 
2.56 
2.62 
Weibull k 
1.602 
1.589 
1.584 
Weibull c (mph) 
17.895 
17.315 
16.631 
1hr autocorrelation coefficient 
0.91 
0.91 
0.91 
Diurnal pattern strength 
0.09 
0.11 
0.15 
Hour of peak wind speed 
14 
13 
13 
Mean turbulence intensity 
0.28 
0.29 
0.30 
Standard deviation (mph) 
10.34 
10.11 
9.82 
Coefficient of variation (%) 
64.5 
65.2 
66 
Frequency of calms (%) 
0.03 
0.03 
0.15 
Possible records 
17,688 
17,688 
17,688 
Valid records 
15,048 
15,575 
15,708 
Suspect records 
2,640 
2,113 
1,980 
Data completeness (%) 
85.1 
88.1 
88.8 
Probability Distribution Function for the 40m Anemometer
Probability Distribution Function for the 25m W Anemometer
Probability Distribution Function for the 10m W Anemometer







Windographer was used to match up the wind at this site with the performance curves of some common turbines of various sizes and various heights. The table below shows the results. For the larger turbines, the tower height was increased to account for the larger turbine blades  the wind resource was extrapolated to these higher heights. Keep in mind that the larger and the higher the turbine, the better the wind and the greater the output. But of course, as the tower heights and turbine sizes increase so does the cost.
Turbine 
Rotor
Diameter
meters 
Rotor
Power
kW 
Hub
Height
meters 
Hub
Height
Wind
Speed
mph 
Time
At
Zero
Output
percent 
Time
At
Rated
Output
percent 
Average
Net
Power
Output
kW 
Average
Net
Energy
Output
kWh/yr 
Average
Net
Capacity
Factor
% 
Bergey ExcelR 
6.7 
7.5 
40 
16.02 
21.23 
9.73 
2.5 
21,500 
32.7 
Bergey ExcelS 
6.7 
10 
40 
16.02 
11.70 
7.13 
2.9 
25,700 
29.4 
Bergey XL.1 
2.5 
1 
40 
16.02 
4.43 
15.42 
0.4 
3,400 
38.5 
Southwest Skystream 3.7 
3.7 
1.8 
40 
16.02 
17.75 
0 
0.6 
5,400 
34.4 
Southwest Whisper 500 
4.5 
3 
40 
16.02 
20.58 
12.53 
1.2 
10,300 
39.2 
Northern Power NW 100/20 
20 
100 
37 
15.87 
18.89 
0 
27.2 
238,200 
27.2 
Vestas V47  660 kW 
47 
660 
65 
16.33 
20.13 
2.69 
200.4 
1,755,900 
30.4 
GE 1.5s 
70.5 
1,500 
80.5 
16.51 
25.62 
10.13 
423.1 
3,706,500 
28.2 
Vestas V80  2.0 MW 
80 
2,000 
100 
16.70 
25.32 
5.95 
629.1 
5,511,300 
31.5 
GE 2.5xl 
100 
2,500 
110 
16.78 
19.95 
10.70 
854.8 
7,487,800 
34.2 
IMPORTANT: No turbine losses are included in the power, energy, and capacity factor values in the table. Typically, turbine losses can be 520% to account for maintenance downtime, icing/soiling and losses from other turbines in a wind farm. Users wanting to be conservative in the performance projections should multiply the power, energy, and capacity values by (1 % losses) to account for these losses.
