High-altitude Wind For Power Purposes
Winds at higher altitudes become steadier, more persistent, and of higher velocity. Because power available in wind increases as the cube of velocity (the velocity-cubed law), assuming other parameters remaining the same, doubling a wind's velocity gives 2x2x2=8 times the power; tripling the velocity gives 3x3x3=27 times the available power. With steadier and more predictable winds, high-altitude wind has an advantage over wind near the ground. Being able to locate HAWP to effective altitudes and using the vertical dimension of airspace for wind farming brings further advantage using high-altitude winds for generating energy.
High-altitude wind generators can be adjusted in height and position to maximize energy return, which is impractical with fixed tower-mounted wind generators.
In each range of altitudes there are altitude-specific concerns being addressed by researchers and developers. As altitude increases, tethers increase in length, the temperature of the air changes, and vulnerability to atmospheric lightning changes. With increasing altitude, exposure to liabilities increase, costs increase, turbulence exposure changes, likelihood of having the system fly in more than one directional strata of winds increases, and the costs of operation changes. HAWP systems that are flown must climb through all intermediate altitudes up to final working altitudes—being at first a low- and then a high- altitude device.
Read more about this topic: High-altitude Wind Power
Famous quotes containing the words wind, power and/or purposes:
“Our courage breaks like an old tree in a black wind and dies,
But we have hidden in our hearts the flame out of the eyes
Of Cathleen, the daughter of Houlihan.”
—William Butler Yeats (18651939)
“The most advanced nations are always those who navigate the most. The power which the sea requires in the sailor makes a man of him very fast, and the change of shores and population clears his head of much nonsense of his wigwam.”
—Ralph Waldo Emerson (18031882)
“I find that the respectable man, so called, has immediately drifted from his position, and despairs of his country, when his country has more reason to despair of him. He forthwith adopts one of the candidates ... as the only available one, thus proving that he is himself available for any purposes of the demagogue. His vote is of no more worth than that of any unprincipled foreigner or hireling native, who may have been bought.”
—Henry David Thoreau (18171862)