Although the return on building new turbines would eventually plateau, that point, which they dubbed saturation wind power potential, won't be reached until there are more turbines than will be needed. That saturation point is more than 250 terawatts, which would require 100-meter-tall wind turbines covering the planet's land and water surfaces.
"We're not saying, 'Put turbines everywhere,' but we have shown that there is no fundamental barrier to obtaining half or even several times the world's all-purpose power from wind by 2030," said Jacobson in a press release. "The potential is there, if we can build enough turbines."
The researchers estimated that half the world's energy needs in 2030 would take about 5.75 terawatts. To figure out how many turbines would be required to meet that amount, the team looked at different scenarios of fixed wind power potential, or the maximum power that can be extracted using a specific number of wind turbines. They found that 4 million 100-feet-high turbines, each producing 5 megawatts, could supply as much as 7.5 terawatts of power, with no significant effect on the world's climate. If half were sited on water, and half sited on land, they would occupy about one-half of 1 percent of the planet's land surface.
Funding for the study came from the National Science Foundation, the US Environmental Protection Agency, and the National Aeronautics and Space Administration High-End Computing Program.