WASHINGTON -- Wind farms could have the ability to make days a little cooler and nights a little warmer, make crops grow better and shift the course of a storm.
All that might sound like science fiction, but researchers are finding such results in their studies of turbines and wind farms.
Downwind of a wind farm, turbines create lower local temperatures during the day and higher temperatures in the early morning and at night, according to a study co-authored by Somnath Baidya Roy, a researcher on turbines and temperatures and an atmospheric sciences professor at the University of Illinois at Urbana-Champaign.
The study used data from a wind farm at San Gorgonio, Calif., in 1989, corroborating model simulations Baidya Roy had run before.
The cooling effect could mean a temperature of about 86 degrees Fahrenheit instead of 93.2 during the day near the surface.
The warming effect could mean about 69.8 instead of 68 degrees at night.
Baidya Roy said wind turbines generate wakes in the air, akin to those that motorboats make in water. You just can't see a turbine's wake.
"The turbulence in the wake, what it does is it kind of triggers a mixing effect in the atmosphere," he said.
He theorizes a turbine's wake mixes cooler air with warmer air, changing the temperature.
To counteract that, the study suggests adjusting turbines' design to cut down on turbulence in their wakes.
It also suggests developing wind farms on sites with already bountiful natural turbulence.
Turbines affect temperatures less in naturally turbulent areas such as the Great Plains.
The area cuts a wide swath down the middle of the country and encompasses much of Texas, including the Concho Valley.
Wind is a plentiful resource in Texas, which has more wind power capacity than any other state -- 10,135 megawatts, according to the America Wind Energy Association's 2011 first-quarter marketing report.
A wind industry advocate was skeptical of Baidya Roy's study.
"As a practical matter, it sounds outlandish, and it's not worth commenting on," said Greg Wortham, executive director of the Texas Wind Energy Clearinghouse based in Sweetwater.
Eugene Takle was intrigued by Baidya Roy's study and what it might mean for agriculture.
Takle is studying how wind farms might affect temperature, evaporation and photosynthesis for corn crops growing in their vicinity.
Turbines are popping up all over Iowa, almost all in agricultural fields, he said.
"Farmers are beginning to ask questions of whether these turbines might have an influence on, for instance, pollination or other factors," he said.
Takle has plenty of access to corn in Iowa as an atmospheric sciences and agricultural meteorological professor at Iowa State University, as well as director of the climate science program.
"If the wind turbines are allowing the crop to be more efficient at photosynthesis, that would be a good thing," Takle said. "But on the negative side, it may be that they're keeping the crop a little bit too warm at night."
Takle and other scientists took some measurements last summer to detect turbines' influence on the corn crop, but they need more research to determine the net effect of wind farms on growing corn.
(Email reporter Trish Choate at email@example.com.)