February 24, 2017
Letters, Michigan

The numbers and letters of wind turbine noise

Huron Daily Tribune | Friday, February 24, 2017 | www.michigansthumb.com

The following is a response to Jeff Smith’s reported comments at a recent Planning Commission meeting. This information fills in some significant gaps to aid the public’s understanding of wind turbine issues.

It’s been reviewed by Richard R. James, INCE, for technical accuracy.

Nighttime wind turbine noise is limited to 45 decibels LAeq. 45dB won’t trigger complaints, heated debates or calls for township zoning withdrawal; the elephant in the room is “LAeq.” The “Leq” portion indicates the maximum average noise over time. Numerous blade passes can generate 51-56 dB yet comply with 45 dB LAeq.

“A” indicates the frequencies measured; but concerned scientists suspect complaints are generated by the unregulated frequencies “C,” or even lower “G.” House walls may filter 15 dBA, but cannot significantly filter dBC, much less dBG. Turbines generate over 100 dBG which penetrates concrete walls with long wavelengths; you can’t “hear” it, but the World Health Organization identifies low frequency noise inside occupied structures as a cause of adverse health effects.

The wind industry will negotiate numbers before letters; the 45 dB LAeq of a 165 ton turbine has been compared to a dishwasher; this half-truth ignores more than it reveals. 45 dB LAeq is a little like requiring cigarettes to come in healthy packaging.

Whatever position you take, life’s too short not to love your neighbor as yourself. May God bless Huron County.

Eric Jefferies

Reed City


URL to article:  https://www.wind-watch.org/news/2017/02/24/the-numbers-and-letters-of-wind-turbine-noise/