Wind speed rises with altitude, and available power rises at
the cube of wind speed.
He knew wind power is related to
the cube of wind speed, so faster winds create exponentially more power than slower ones.
For example tropical storms (hurricanes) don't form unless the sea surface temperature reaches a threshold temperature (~ 26.5 oC according to William Gray) and the while the hurricane wind speed increases around 5 % for each 1 oC of temperature rise, the destructive power in monetory terms increases with something like
the cube of the wind speed (e.g. Emanual Nature 436, 686 (2005)-RRB-.
The potential energy produced from wind is directly proportional to
the cube of the wind speed.
Since wind power is proportional to
the cube of the wind speed, higher wind speeds result in much higher power.
Keep in mind that the power of wind increases as
the cube of the wind speed.
Strictly speaking, the power of the wind is proportional to
the cube of the wind speed.