June 18, 2009

High altitude wind power studied

U.S. scientists considering wind power tapped by high-flying kites say New York City is a prime location for exploiting high-altitude winds.

Ken Caldeira of the Carnegie Institution and Cristina Archer of California State University have compiled the first global survey of wind energy available at high altitudes and say such winds contain enough energy to meet world demand 100 times over.

There is a huge amount of energy available in high altitude winds, Caldeira said. These winds blow much more strongly and steadily than near-surface winds, but you need to go get up miles to get a big advantage. Ideally, you would like to be up near the jet streams, around 30,000 feet.

Included in the analysis were assessments of high altitude wind energy for the world's five largest cities: Tokyo, New York, Sao Paulo, Seoul, and Mexico City.

While the scientists found there is enough energy in high altitude winds to power all of modern civilization, there are still times when the winds do not blow.

This means that you either need back-up power, massive amounts of energy storage or a continental or even global scale electricity grid to assure power availability, Caldeira said. So, while high-altitude wind may ultimately prove to be a major energy source, it requires substantial infrastructure.

The researchers detail their findings in the journal Energies.