Wind power can play a greater role than currently supported in meeting most or bulk of global energy demand, a report from Stanford and Delaware universities says.

Scientists used a sophisticated climate model to argue that wind as an energy resource can satisfy "half to several times" the world's total energy needs within the next two decades.

Wind farms have drawn criticism worldwide for being cost-inefficient, eyesores on pristine rural or seaside landscapes and noisy. Supporters of wind energy's greater use contest most of those criticisms.

"If the world is to shift to clean energy, electricity generated by the wind will play a major role and there is more than enough wind for that," Andrew Myers, a spokesman for the Stanford University School of Engineering said.

Mark Z. Jacobson, a professor of civil and environmental engineering at Stanford and co-author of the report said, "The careful siting of wind farms will minimize costs and the overall impacts of a global wind infrastructure on the environment."

The findings were published in the proceedings of the U.S. National Academy of Sciences by Jacobson and Cristina Archer, an associate professor of geography and physical ocean science and engineering at the University of Delaware.

The report contradicts two earlier studies that said each turbine steals too much wind energy from other turbines and that turbines introduce harmful climate consequences that would negate some of the positive aspects of renewable wind energy.

The report calculated the number of wind turbines needed to meet half the world's power demand, about 5.75 terawatts, in a 2030 clean-energy economy. They said that 4 million turbines would do the job.

The 4 million turbines producing 5 megawatts each could supply as much as 7.5 terawatts of power, or more than half the world's power demand, without significant negative effect on the climate.

"To get there, however, we have a long way to go," Jacobson said. "Today, we have installed a little over 1 percent of the wind power needed."

Jacobson and Archer recommend siting half of the 4 million turbines over water. The remaining 2 million would require a little more than one-half of 1 percent of the Earth's land surface, about half the area of Alaska.

High-wind sites including the Gobi Desert, the American plains and the Sahara Desert are prime candidates for the installations, they said.

"As these results suggest, the saturation of wind power availability will not limit a clean-energy economy," Jacobson said.

The Environmental Technology Center at the University of Nottingham, England, has published 15 "myths" about wind power to debunk each with a "fact."

"Many people make many claims about wind turbines and the effects that they allegedly have. We've collated our favorites and given the answers," the university said on its website. Nottingham runs international campuses in Ningbo, China; and Semenyih, Malaysia.