Study Points to Wind Farms Killing Bats

A Canadian study suggests the low pressure created around wind farms is the culprit in killing large numbers of bats around wind turbines.
The risk that wind turbines pose to birds is well known and has dogged debates over wind energy. In fact, several studies have suggested the risk to bats is greater. In May 2007, the U.S. National Research Council published the results of a survey of U.S. wind farms showing that two bat species accounted for 60 percent of winged animals killed.
Migrating birds, meanwhile, appear to steer clear of the turbines.
T. Boone Pickens, who owns a wind company, has been spending millions promoting wind as an alternative energy source.
Laurie Jodziewicz, manager of siting policy for the wind industry, said the industry is alarmed and studying the problem. The industry is looking at a warning system for bats. Also, turbines could be programmed to come on at higher wind speeds.
Bats echolocate moving objects. Why turbines appear to kill them has remained a mystery. The research council thought the high frequency from the turbines’ gears and blades could be disrupting the bats’ echolocation systems.
In fact, a new study shows that the moving blades cause a drop in pressure that makes the delicate lungs of bats suddenly expand, bursting the tissue’s blood vessels. This is known as a “barotrauma,” and is well known to scuba divers.
“While searching for bat carcasses under wind turbines, we noticed that many of the carcasses had no external injuries or no visible cause of death,” said Erin Baerwald of the University of Calgary in Canada.
Baerwald and colleagues collected 188 dead bats from wind farms across southern Alberta, and determined their cause of death. They found that 90 percent of the bats had signs of internal hemorrhaging, but only half showed any signs of direct contact with the windmill blades. Only 8 percent had signs of external injuries but no internal injuries.
California’s Santa Barbara County, considered by to be some the birthplace of the modern U.S. environmental movement, is considering changing its decades-long opposition to renewed offshore drilling.
The move would impact the stretch of Pacific coast about 100 miles northwest of Los Angeles.
The five-member county Board of Supervisors could write Gov. Arnold Schwarzenegger to ask for a change of state policy against drilling.
The Bureau of Land Management issued a proposed resource management plan and final environmental impact statement for the Pinedale, Wyo., field office to help direct planning for lands and resources in the state’s natural gas-rich Sublette and Lincoln counties.
Enbridge Energy Partners LP and Atmos Pipeline and Storage LLC have launched an open season to solicit firm transportation for Barnett Intrastate Gas Pipeline.
As proposed, the pipeline would carry up to 1 billion cubic feet of gas a day and connect Atmos’ Line X in Johnson County, Texas, to Enbridge’s Double D and Clarity pipes at Bethel, Texas.
Any concerns that recent changes to the Energy Information Administration’s natural gas storage reporting sampling process might affect energy markets appear unfounded.
The government agency reported little difference in the old and new samples. But, that the new sampling procedure produced more accurate estimates.
Alaska Gov. Sarah Palin signed an executive order sets in motion work on a liquefied natural gas project that would transport LNG from the state’s North Slope for tanker export to international markets.
“Alaska has huge supplies of both renewable and non-renewable energy,” Palin said. “With the Legislature’s recent approval of the Alaska Gasline Inducement Act, ANGDA must continue its work to make Alaska natural gas available to Alaskans.” ?



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