Last login: Tuesday, March 20, 2012
The early Altamont and Tehachapi turbines turned at about 72-80 rpm but the tip speed was only 125 mph (184 ft sec) because the blades were only 22 ft long. The new turbines have blades 150 ft long and when spinning at 20 RPM have a blade tip moving at 314 ft per second or 214 mph. The slower rpm moving blades also fool birds more because they see right through illusive openings between the blades and think they can fly through them. Here is the math for the so called new safer turbines. 1) A single blade on a 300-400 foot turbine with 150 foot blades slowly moving at 20 rotations per minute will equal a circle with a 300 foot diameter. At 20 rotations each blade tip is moving 20 x 300 x 3.14 feet per minute =18840 feet per minute divided by 60 which equals 314 ft per sec or 214 miles per hour.
March 20, 2012 at 10:04 a.m.
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"The term "fast track" is purposely designed to restricted public participation and consultation with affected parties. A more appropriate term for this wind industry strategy would be "ambush" or "Rigging". These wind farms are planned years before the public even hears about it. Then the project designers create all their phoney reports. I read their report. Their radar will not work and the local eagles will be killed of in this habitat. Generations of Eagles that have used this area for thousands of years will be exterminated. There has been a 50 decline in the golden eagle population near Altamont since 2005. Despite wind industry claims, the new bigger turbines are not safer. This notion was based on the very flawed Smallwood studies at Altamont. His studies did however prove that the taller bigger turbines actually Kill more eagles. I went into detail about this in the Repowering Altamont with Smoke and Mirrors article. As for being safer for all other birds, the Smallwood studies are completely meaningless because of the deliberately undersized (75 Meter)search areas and the comparison to other habitats that had far more bird species. If search areas were a 200 meter radius and the comparisons were made in the same semi desert habitat, then the studies might have some credibility. The industry knows that birds hit by the turbines do not just fall within a 50-75 meter radius of wind turbines. Even the early small turbines 40-65KW threw birds 200 feet or more. Now with these huge turbines(20-45 times bigger with blades moving faster) it is a totally different story. readers should search the internet for the Watertown Daily Times 12/15/11 article about the dead geese. The turbines threw these geese all over the place. Yet by the wind industry mortality standards, any of the geese more than 75 yards away from a turbine would not make it into the rigged methodology of wind industry mortality studies. And then there are the uncounted mortally wounded that wander around for days.
Here is the truth about the wind industry impacts to birds. At least 3 million birds are killed annually in the US from Wind Turbines. All the current estimates we hear in the media are based on industry approved, completely flawed studies. The Propeller style wind turbine will never be safe unless tip speed is reduce to around 50 mph.
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