The Government has announced a review of wind farm noise after a long campaign by a Devon community.
Neighbours of the planned Den Brook project, which will be the third biggest in the Westcountry if built, brought a judicial review after concerns over the amplitude modulation noise (AM). The noise from “wind shear” is said to be the cause of most complaints but is not included in planing law.
A High Court judge upheld West Devon Borough Council’s approval of a scheme to measure a decision which locals are seeking to appeal.
Now the Department of Energy and Climate Change (DECC) has announced a review on wind turbine amplitude modulation noise which could set a national standard.
Review the evidence
DECC says it will appoint acoustics experts to review the evidence with a view to providing guidance for planning authorities and developers.
The Den Brook Judicial Review Group has welcomed moves to set a standard for the noise but is concerned vested interests in the industry could influence the study.
RenewableUK, the industry’s lobby group, claims the wind industry has been “taking the lead” in turbine acoustics and has used research to minimise sound levels.
Mike Hulme, a leading member of the Den Brook group, who lives less than a mile away from the nearest of nine planned turbines, said it was crucial the study was impartial.
“Wind developers have been in denial of AM for many years, building wind turbines without accounting for this noise,” he added.
“One difficulty is that AM is not a loudness problem – it is not the noise level but the pulsating nature of the noise.”
When granting planning permission for a wind farm the Planning Inspectorate relies on a 15-year-old noise assessment methodology known as ETSU-R-97 that sets noise limits based on loudness, therefore failing to control AM noise.
Noise nuisance complaints
Mike Stigwood of MAS Environmental says the failing is responsible for all of the 70 cases of noise nuisance complaints he has on record.
DECC has not yet revealed who will be doing the work, a major source of unease among campaigners.
The department intends to launch a tendering process for “acoustics experts”, with a review of available evidence concluding in the spring.
The Institute of Acoustics, which asked DECC to commission a study to look at an appropriate threshold, welcomed the announcement.
RenewableUK’s director of onshore renewables, Gemma Grimes, said their commissioned independent desktop research carried out two years ago found the sound by a number of universities and professional acoustic bodies including the University of Salford “helped us to pinpoint when, where and how this sound varies”.
“We found that this “can be addressed by using computer software to adjust the way turbines operate, changing the angle of the blades to minimise the sound levels”.
She added: “We’re hoping that this will now be incorporated within the Institute of Acoustic’s existing Good Practice Guidance document”.