The developer predicts that his wind farm may kill five golden eagles over 25 years, but such forecasts have proven wrong in the past by a factor of 10 to 50 times.
Radar mitigation at wind farms to cause more deaths
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Save the Eagles International (STEI) and the World Council for Nature (WCFN) denounce the use of ineffective mitigation to prevent bird and bat collisions at wind farms. Developers claim that their radar systems will detect birds and bats, and shut off wind turbines to avoid collisions. STEI and WCFN warn that this new mitigation scheme will actually increase bird and bat mortality worldwide.
For instance, an “avian radar” will be installed in the middle of the proposed Ocotillo wind farm in Southern California, which will stand in a migration flyway for golden eagles and other protected birds (1), while overlapping local golden eagle breeding territories and the habitat of some endangered species. The 112 wind turbines of 2.3 MW each will reach 456 feet into the sky with a combined rotor sweep equal to that of all the eagle-killing turbines of Altamont Pass. The blades will have a faster tip speed at 174 mph when rotating at 16 rpm, and STEI notes that it has been proven larger turbines kill more eagles than smaller ones (2).
The developer predicts that his wind farm may kill five golden eagles over 25 years, but STEI points out that the obvious conflict of interest renders his prediction worthless, and that such forecasts have proven wrong in the past by a factor of 10 to 50 times. Accordingly, real mortality could be “anywhere between 50 and 250 golden eagles”, says its president Mark Duchamp, “...and possibly more. Who would have thought that the Altamont Pass wind farm would have killed 2,900 golden eagles to date?”
For STEI and WCFN, the radar system offered as mitigation will not be effective. In the words of Jim Wiegand, STEI’s Vice President for the United States, “The use of radar at Ocotillo will fail due to several reasons: human error, blind spots, interference, bats and smaller birds being excluded from its protection, the far too long 60-second shut-down delay, flights upwards from below the rotor-swept zone and flights downwards from above the rotors (there won’t be sufficient time to stop the turbines), and above all a greed-driven reluctance to shut down the turbines, forego some income, wear down the brakes, etc.”
Adds Duchamp: “radars are already in operation at several wind farms in the world, and the results as dismal. At the Kenedy Ranch, Texas, one wind farm has officially been estimated to have killed 921 birds and 2,309 bats in a little less than a year, and another one nearby 1,812 birds and 3,087 bats in the same period (3). Real-life figures are likely to be higher, explains the author of the referenced article. He also notes that over one and a half years of operation the radar did not shut down the turbines once: ‘As of the end of 2010, a shutdown had not occurred’ (3).”
Thus, radars are yet another lure for the gullible, warns Mark. “Thanks to this alibi, more wind projects will be authorized to be built in migration corridors and other hot spots for wildlife, resulting in even more deaths of protected species. It will allow decision-makers to wash their hands saying ‘the radars will save the birds’; but that’s untrue.”
On June 11th, 2010, ornithologist David Newstead reported from the Kenedy ranch wind farm: “We watched as the pelicans continued soaring between us and the turbines. It appeared that they were getting closer and closer to the next turbine, but it was hard to get a handle on how close they actually were. Finally, they were approaching one of the most easterly turbines in that particular string, and we watched as the last bird in the group was struck and literally ‘erased’ from the air (a blade is about the width of a city bus, and moving about 180 mph). It was flying at or just below hub height, and was hit on the downstroke” (4). - So much for the radar! quips Wiegand.
(1) – Golden eagles and other raptors observed migrating at the site: table 6, p. 15 overlapping golden eagle breeding territories: 2.1.2 p. 6
(2) – Wind turbines with a capacity of 1MW, wrote Dr Shawn Smallwood, kill more golden eagles per megawatt than most smaller wind turbine categories: 0.08 per MW /year as compared to about 0.04: page 41, table 5
(3) – Source: MY SAN ANTONIO online
(4) – Source: SURFBIRDS