High altitude winds are one of the largest untapped renewable resources in the world. Professor Ken Caldeira of the Carnegie Institute for Science at Stanford University published research on the sector and concluded;
“There is enough energy in high altitude winds to power civilization 100 times over.”
High altitude winds are more consistent and average around twice the velocity, with five to eight times the power density, than those found near ground-level. In the U.S. alone, over 60% of potential wind sites for tower-mounted systems were found to be uneconomical.
The advent of airborne wind technology holds the potential to bring affordable wind energy to these sites.
 Average wind power density at Caribou, ME between 1990 and 2010. (Source: Integrated Global Radiosonde Archive)
 Photo used under Creative Commons license, with permission from Sanderovsky. http://flic.kr/p/icBVx.