Wind Turbine Noise: What you can’t hear can harm you.
by BRIAN DUBIE on October 6, 2015 at 9:33pm
Wind Turbine Noise: What you can’t hear can harm you.
What do you think of when you think of an industrial wind project? Wind developers want you to think of free, green electricity. People who live near industrial wind turbines think of noise. Let’s see why.
An Industrial Wind project in Swanton proposes to install seven 499-foot tall wind turbines along 6,000 feet of Rocky Ridge (elevation 323 feet). We recently learned that the developer of this proposed project plans to use Chinese made, Gold Wind 2.5mw turbines. The Chinese manufacturer Gold Wind http://www.goldwindamerica.comdoes not even list the noise rating of this turbines. Hiding a noise rating from the public is bad omen for proper siting for an industrial wind turbine. Let’s assume that the developer will use a GE 2.75-120 Wind Turbine. At 475 feet, it is slightly smaller than the developer’s Swanton turbines. GE says a single one of their 475-foot monsters can produce 106 dBA of noise. Scaling up to seven turbines would increase that noise to 109 dBA. (Noise is measured as pressure on a scale that is logarithmic, so sometimes the numbers are difficult to understand, but 109 dBA is loud. For comparison, my chain saw is rated at 109 dBA. I wear ear protection when I use it.)
So, when you think of industrial wind turbines on a ridge line, envision an airport with a line of airplanes that are holding for take-off. The airplanes are powered by chainsaw engines that have run up their engines to full power. But, unlike planes at an airport, the turbines never take off. Now, imagine this at 2am in the morning.
Some people will say wind turbines are not that noisy. Well that depends on how far from the turbines (chainsaws) and how many turbines (chainsaws) there are. Sound attenuates over distance. The further you are from the turbines (chainsaws) the more the noise attenuates and thus the quieter the sound is. Noise attenuation is also dependent on many topographical and meteorological factors. For example if you are downwind from the turbines (chainsaws) the noise is greater. If the turbines (chainsaws) are located on high ground, the noise carries farther. (more…)