May 12 2009

Wind Industry Tackles Wildlife Woes

Posted by: Jonathan Marshall

What could be greener than clean, renewable wind power? Unfortunately, a lot of environmentalists instead see red when considering the deadly impact of wind turbines on birds and bats.

Bird kills have been a fact of life for many years at Altamont Pass; by one government biologist's estimate, more than 400,000 birds are killed each year across the country by wind turbines. On the East Coast, biologists began sounding the alarm several years ago over their discovery of thousands of bat carcasses, battered and bloodied by blows (or rapid pressure changes) from turbine blades. Peak mortality tends to be in autumn, during bat migration and mating season.

Instead of covering up the problem, the wind industry to its great credit is trying to better understand and solve it. Today, researchers sponsored by the wind industry reported a breakthrough in lowering bat mortality by turning off turbines during low-wind periods at night.

At least 70 percent fewer bats were killed at a Pennsylvania test site owned by Iberdrola Renewables, the world's largest wind energy company, simply by curtailing operations when bats are most active. Because wind speeds were low, the company suffered only small losses in generation.

The research, which will continue for another year, is being sponsored by Iberdrola and the Bats and Wind Energy Cooperative, a coalition of the American Wind Energy Association, the U.S. Fish and Wildlife Service, the National Renewable Energy Laboratory and Bat Conservation International.

The U.S. Department of Energy is a major supporter of systematic research into minimizing the wildlife impacts of wind turbine siting. On May 6, Secretary Chu announced a dozen new grants in this field totalling nearly $2 million.

Researchers aren't quite sure why bats fly into harm's way. Some believe bats investigate the giant turbines for roosting places; others think they are foraging for insects that are attracted to the light-colored towers at night.

"Many of us don't believe they are randomly flying into the turbines," said Dr. Ed Arnett, lead researcher on the Pennsylvania study, in an interview with NEXT100. "From thermal images you can see bats investigating the turbines. They are curious, very different from birds."

The wind industry is making progress on reducing bird kills as well. At a huge wind farm in Texas, Iberdrola is using advanced radar systems to detect the flight path of migrating birds and automatically shut down the turbines to prevent feathers from flying.

The wind industry's efforts to reduce wildlife kills, it should be noted, are extending its already exemplary environmental record. A study released in March by the New York State Energy Research and Development Authority found that wind energy poses fewer wildlife risks in all respects than coal, oil, natural gas, nuclear or hydro power. (The study didn't encompass solar power.)

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