MessageFrom: L. Van Warren [van@wdv.com]
Sent: Wednesday, July 16, 2008 4:44 AM
To: van@wdv.com
Subject: notes on height

the tower exists not so much for variation of wind speed with height, but rather as setting a minimum height for clearance of obstacles and turbulence generators.

the tower must be such that the center of the hub is 20 feet taller than any feature for 300 feet, especially in the prevailing wind direction.

the variation of wind speed with time is much more significant to use than variation of wind speed with height, we modulate height to maximize clearance from wind shadow during times of low wind, and to utilize wind shadow during times of high winds.