Harvard Study says there is a lot more wind power

Global wind energy potential is considerably higher than previous estimates by both wind industry groups and government agencies, according to a Harvard University study published last week in the Proceedings of the National Academy of Sciences of the United States.

Using data from thousands of meteorological stations, the Harvard team estimated that world wind power potential to be 40 times greater than total current power consumption. A previous study cited in teh paper put that multiple at about 7 times.

In the lower 48 states, the potential from wind power is 16 times more than total electricity demand in the United States, the researchers suggested – significantly greater than a 2008 Department of Energy study that projected wind could supply a fifth of all electricity in the country by 2030.

The authors based their calculations on the deployment of 2.5- to 3-megawatt wind turbines situated either in accessible rural areas that are neither frozen nor forested, or relatively shallow offshore locations. They also used a conservative 20 percent estimate for capacity factor, a measure of how much energy a given turbine actually produces.

In an example of how renewable energy potential can be a moving target, Mr. Goggin explained that the growth in the forecasts can be attributed to the increasingly common use of very large turbines that rise to almost 100 meters.

Wind speeds are greater at higher elevations. Previous wind studies were based on the deployment of 50- to 80-meter turbines.

"As turbines start to get taller," predicts Mr. Goggin, "we'll see a lot more capitalization of the resource."

Power from wind turbines increase as a factor of the cube of of wind velocity.