The amount of energy in wind increases as the cube of its speed, so a 10 mph winds has 8 times the energy as a 5 mph wind. This is why wind power developers look for sites with high wind speeds. Of course, the reliability of the wind is also important in siting a wind turbine. As it turns out, there is a wind power site near to almost all of us, that has very reliable, very high wind speeds—about 1 kilometer straight up. Wind near the Earth’s surface is slowed down by drag across the surface, so as one goes further away from the Earth, wind speeds, and wind consistency, increase.
While only about half a mile away, it is difficult to site a wind turbine at such altitude. Kites offer a way of accessing the significant energy source so near at hand. Many ideas have been developed over the years but none have taken off. There are a few cargo ships testing large kite assists that show promise (see Kite Ship and Sky Sails). A new entrant, Makani Power, is appearing over the horizon. Headed by Saul Griffiths, and funded by Google, the company brings a new approach, passion, and creativity to the challenge. Saul is also involved in a number of other interesting and innovative projects, which can be surveyed at his web site. A presentation he gave at TED in Feb 2008 can be seen here. The amount of energy available is as enormous as the cost promises to be low. Stay tuned.
Posted by Michael Morrison 
