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View Full Version : Wind Energy ... Oops!



Gerry Clinchy
05-05-2012, 06:40 PM
The latest in "unintended consequences" is that the large wind farms cause an increase in surface temperature at the base of the turbines. Even "alternative" and "green" energy sources are not without some consequences!

http://www.foxnews.com/scitech/index.html




Researchers used satellite data from 2003 to 2011 to examine surface temperatures across as wide swath of west Texas, which has built four of the world's largest wind farms. The data showed a direct correlation between night-time temperatures increases of 0.72 degrees C (1.3 degrees F) and the placement of the farms.

"Given the present installed capacity and the projected growth in installation of wind farms across the world, I feel that wind farms, if spatially large enough, might have noticeable impacts on local to regional meteorology," Liming Zhou, associate professor at the State University of New York, Albany and author of the paper published April 29 in Nature Climate Change said in an e-mail to Discovery News.




FAA data shows that the number of wind turbines over the study region has risen from 111 in 2003 to 2358 in 2011, according to the study.The warming could hurt local farmers, who have already suffered through a killer drought over the past few years. Texas agriculture contributes $80 billion to the state's economy, second only to petrochemicals, according to the Texas Department of Agriculture.

West Texas is a dry area that uses irrigation to grow wheat, cotton and other crops, as well as raise cattle. But increased warming can play havoc with plant growth, as well as change local rainfall patterns.

Texas wind farms produce more than 10,000 megawatts of electricity, more than double the capacity of the nearest state, Iowa, and enough to power three million average American homes, according to the American Wind Energy Association.



"Smaller turbines can avoid this problem," Dabiri said. "However, this presents a tradeoff, because wind speed decreases as you move closer to the ground; so the smaller turbines would experience lower incoming wind speeds on average."

That means a smaller turbine makes less power.

Dabiri said Zhou's findings may mean taking a second look at the trade-offs with renewable energy. "It shows that we need to think carefully about the unintended environmental consequences of any large-scale energy development," Dabiri said, "including green technologies."

Zhou cautioned that his study used satellite data, which can have errors from clouds, for example, rather than temperature readings taken at the surface. He said he hopes to improve his dataset, and look at wind farms in other parts of the world.