Wind speeds are calculated at 80 m, the hub height
of modern, 77-m diameter, 1500 kW turbines. Since
relatively few observations are available at 80
m, the Least Square extrapolation technique is utilized
and revised here to obtain estimates of wind speeds
at 80 m given observed wind speeds at 10 m (widely
available) and a network of sounding stations.

Tower data from the Kennedy Space Center (Florida)
were used to validate the results. Globally, ~13%
of all reporting stations experience annual mean
wind speeds ≥ 6.9 m/s at 80 m (i.e., wind
power class 3 or greater) and can therefore be considered
suitable for low-cost wind power generation. This
estimate is believed to be conservative.

Of all continents, North America has the largest
number of stations in class 3 (453).