November 14, 2005
General News

Bat deaths cast pall over promise of wind power

Owned by Juno Beach-based FPL Energy, a sister company of Florida Power & Light, they are part of the national effort to develop diverse – and more environmentally friendly – energy sources.

The problem is, they’re killing thousands of bats a year.

Touted by the power industry and some environmentalists as among the cleanest methods of generating electricity, wind farms are opposed by other environmentalists and mountain denizens, who say they kill too many bats and birds, disturb other wildlife and spoil the landscape.

“I can appreciate that we need other energy sources,” said Jane Burch, who lives in neighboring Grant County, W.Va., where another large wind farm has been proposed. “But I don’t like the look of them, and I don’t want them behind my property, and I don’t like what they do with the bat kills.”

In the small towns and farms of the West Virginia and Pennsylvania mountains, the battle over whether to allow more wind farms on the ridges – where unobstructed breezes produce a steady source of potential power – has become a hot topic.

Supporters say wind energy is both environmentally friendly and a boon to local governments.

Harold Nicholson, chairman of the Meyersdale Windpower Fund Committee – which allocates the roughly $13,000 a year that FPL Energy gives to the Pennsylvania community in lieu of taxes for the 20-turbine Meyersdale Wind Energy Center – said the windmills are “a low-cost, environmentally clean source of electrical power, and I support anything that will provide electric power for now and future generations.”

Opponents say the windmills are an eyesore, create noise pollution, kill bats, startle livestock with the flickering of sunlight through the blades, decrease property values and could harm tourism.

“I think we have gone through a lot of desecration of our ridge for something that is not worth it,” said Don Walukas, former borough council president of Meyersdale. “I sit on my porch, and I see those things. What if they have them all over the place? I’m not ready for that.”

But the U.S. Department of Energy is ready.

Wind now generates less than 1 percent of the nation’s electricity, and the Department of Energy wants to raise that to at least 5 percent by 2020.

More turbines planned

About 600 new turbines are planned within 70 miles of the existing West Virginia and Pennsylvania wind farms. If they are built, more than 50,000 bats a year could be killed in those two states alone, said Merlin D. Tuttle, founder and president of Austin, Texas-based Bat Conservation International Inc.

“They can’t sustain that kind of kill rate,” Tuttle said, noting that bats are among the slowest-reproducing mammals – generally one pup each year, although some species have two to four.

“Bats are just as important by night as birds are by day,” he said. Indeed, bats play an important ecological role by eating mosquitoes and such crop-destroying insects as moths, locusts and grasshoppers.

Contrary to popular belief, bats have quite good vision. That vision is enhanced by a radar-like system known as echolocation, which helps them “see” in the dark and enables them to zero in on insects as small as a gnat.

Yet, they’re being killed by turbines in almost every location where they have been erected. No one knows exactly how many.

Two studies of FPL Energy wind farms found that thousands of bats were being killed in the Appalachian Mountains.

A seven-month study conducted in 2003 at the Mountaineer Wind Energy Center in West Virginia found that an average of 48 bats were killed at each of the 44 turbines there. That’s a rate of about seven bat deaths a month for each turbine, or more than 2,100 for the entire wind farm over the seven-month period.

A more intensive study this year estimated even higher death rates. The six-week study – led by Edward B. Arnett, a scientist with Bat Conservation International, and financed largely by the American Wind Energy Association – found 38 bat deaths per turbine at the Mountaineer facility and 23 bat deaths per turbine at the Meyersdale facility.

Because scavenging birds and animals may have carried away many carcasses, scientists estimate the number of bats killed during the six-week period was roughly 1,300 to 2,000 at Mountaineer and 400 to 660 at Meyersdale.

How to save bats debated

It’s unclear precisely why windmills kill bats. Among the theories are that the windmills are located in the bats’ migratory path; that bats may be attracted by the turbines’ humming sound, their flashing lights to warn aircraft or their tall masts, suitable for roosting; or that the short range of the bats’ echolocation does not give them enough time to avoid the spinning blades.

The Mountaineer study may provide a clue. During the study, one of the turbines at Mountaineer was out of service. It was the only turbine where no bat fatalities were recorded during the entire period.

That led bat enthusiasts to conclude bats are not colliding with stationary blades. They’re being hit by moving blades, said Dan Boone, a wildlife biologist from Bowie, Md.

The study’s completion in June has led to an impasse between bat conservationists and the wind power industry over what to do next.

Conservationists have called for further studies that would disengage some turbines by “feathering” the blades during low wind speed nights.

They note that the study showed most bats were killed on nights when the wind speed was less than 9 mph, while the fewest were killed on nights when wind speeds were above 13 mph.

That could be because bats and the insects they feed on generally do not fly on windy nights, Boone said.

Feathering the blades during relatively calm evenings could quickly answer the question of how many bats might be saved and how much potential energy would be lost, Tuttle said.

But Steve Stengel, spokesman for FPL Energy, said there would be technical problems, including increased wear and tear, if the blades were feathered.

Instead of feathering the blades, the wind power industry has proposed studies of deterrent measures such as acoustics to discourage bats from approaching the turbines. If preliminary investigations show promise, field tests might take place next year, and FPL Energy has offered to allow some of its facilities to be used for such tests.

“We don’t think it makes a whole lot of sense to be focusing on a solution that potentially could reduce the amount of power that is generated,” Stengel said. “We think there needs to be a great deal of effort put into finding ways for bats and wind turbines to coexist.”

http://http://www.palmbeachpost.com/politics/content/local_news/epaper/2005/11/14/c1a_fplbats_1114.html


URL to article:  https://www.wind-watch.org/news/2005/11/14/315/