Acoustic Experts Express Concern About Potential Noise Impact of Micro-wind Turbines
Acoustic experts have warned that a government proposal allowing the installation of wind turbines on homes and businesses without planning permission could lead to increased nuisance complaints and noise abatement notices.
The UK’s leading professional body for acoustics, noise and vibration, the Institute Of Acoustics, also said that the 45 decibel maximum noise level mooted in the consultation document would lead to “an unacceptable erosion of residential amenity”.
The IOA’s comments were contained in its submission to the government’s proposed “Permitted development rights for small scale renewable and low carbon energy technologies, and electric vehicle charging infrastructure”.
It was one of about 190 responses to the document, in which the Government proposes measures to cut carbon emissions via a relaxation of planning rules, for example allowing homeowners, developers and businesses to install their own on-site turbines and air source heat pumps without needing to make a planning application.
The Institute said that permitted development rights “should not be extended to micro-turbines and air source heat pumps to be installed at domestic and non-domestic properties”.
But, “if the Government considers that the benefits of the scheme outweigh the disadvantages, a lower noise limit of 35 dB … should be used to reduce the risk of nuisance or disturbance”.
The IOA said that to allow wind turbines mounted on detached homes or freestanding outbuildings and air source heat pumps on domestic premises to have a maximum noise level of 45 dB at one metre from the window of neighbouring premises would lead to “an increased risk of an adverse noise impact”.
If an absolute noise criterion had to be adopted, this should be limited to 35 dB “as a precautionary measure,” the experts said.
However, the specific noise limit proposed did not ensure that the permitted development had no significant impact beyond the host property.
“The IOA believes that the proposed limit of 45 dB … is likely to be significantly higher than pre-existing background noise levels in many residential areas, particularly at night, and is, therefore, likely to give rise to disturbance and claims of nuisance.
“This is consistent with the findings of noise specialists advising DEFRA, who have concluded that a 10 dB difference between background noise levels and noise levels from wind turbines could occur in up to 97% of cases.
“To put this into perspective, for those not familiar with the way noise is perceived, if a micro-turbine noise level of … 45 dB was permitted where the noise level was previously 35 dB … the neighbour would judge this new noise to be twice as loud as the pre-existing noise.”
The IOA pointed out that the consultation document did not determine whose responsibility it was to ensure installation complied with proposed criteria:
“It is therefore difficult to see how the proposals can be enforceable. Is the responsible body to be the local planning authority, the installer, the occupant, or the owner who proposes to install the device at the host property?”
Please see here for the IOA's review of the proposed permitted development rights
• Comments in the IOA’s review of the “Permitted development rights for small scale renewable and low carbon energy technologies, and electric vehicle charging infrastructure” are the consensus view of the Environmental Noise Group committee, representing the 1,425 members of the IOA’s Environmental Noise Group, which is formed by members who specialise in environmental noise issues as acoustic consultants, local authority officers and academics.
• IOA members are active in research, educational, environmental and industrial organisations and in the development of UK, European and International Standards.