FAQs
Are wind turbines noisy? (1.5.1)
Modern turbines are actually very quiet.. Thanks to advances
in wind turbine technology, well designed, well sited turbines
can be quiet enough to cause no disturbance to people living
just a few hundred metres away.
At these distances, any noise they do make is usually drowned
out by the natural noise of the wind itself in the trees and
vegetation. To protect nearby residents from any undue disturbance,
proposals to install wind turbines are required to meet strict
noise standards. They must comply with a national New Zealand
Standard (NZS 6808: 1998 Acoustics: The Assessment and Measurement
of Sound from Wind Turbine Generators) which states that sound
levels "measured at the boundary of any residential site
must not exceed the greater of 40 decibels or background noise
plus 5 decibels". To put this standard into perspective:
- The sound of people whispering is about 30 decibels
- Refrigerators are about 43 decibels
- Normal speech is about 45 decibels
- A typical vacuum cleaner registers at about 70 decibels
Having read exaggerated claims in the press, people visiting
wind farms are often surprised at how quiet they actually are.
A conversation can be carried out at the base of a modern operating
turbine without raising one's voice. The Scottish Executive
public opinion survey, for example, is one of several demonstrating
that concerns about noise are often unfounded.
Before construction of the Scottish wind farms studied, 12%
of people living near the sites thought that the turbines
would cause a noise nuisance, but after construction, when
people had experience of the wind farm operating, only 2% thought
they were noisy.
For more information: see the literature review "Low
Frequency Noise and Infrasound from Wind Turbine Generators"
prepared for the EECA by Bel Acoustic Consulting.
Notes:
(1) www.mori.com/polls/2003/windfarm.shtml
Back to FAQs |
