
155Wind Energy
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on temperature, weather, geographic location (elevation and terrain), and time (of day and
season). The power law prole is typically used in engineering studies.
Consider Table 3.4 that shows the calculated wind speeds for two different values of α at
a height of 100 m, which is the typical hub height for modern commercial WTs. The change
in predicted power based on these wind speeds is the ratio (13.6/11)
3
= 1.89. This indicates
that the predicted power can nearly double at 100 m if the value of α increases from 0.14 to
0.23. This has large economic implications. In other words, determining the ...