Work Package Title: The Fundamentals of Amplitude Modulation of Wind Turbine Noise
Dr John Yelland investigates the science behind wind turbine noise and amplitude modulation. The objective of WP1 is defined as:To provide a technical description and definition of a characteristic of wind turbine noise that has become known as amplitude modulation and to investigate its measurement, its possible causes and any feasible mitigation.
Work Package Title: Review of Reference Literature
Richard Cox presents the results of a review of the available literature on wind turbine noise (WTN). Over 160 documents are included in the INWG study of amplitude modulation and of these at least 85 documents can be considered technical in content. This contrasts with the IoA AMWG literature review, which lists a total of just 35 documents.
The objectives of INWG WP 2.1 are defined as:
- Review the evolution of knowledge regarding WTN and AM;
- Collate the reference literature relevant to this INWG study and produce a common reference list for the study work packages;
- Provide a short description of each reference document.
Work Package Title: AM Evidence Review
Sarah Large looks primarily for evidence of audible amplitude modulation noise in support of its existence and prevalence. Amplitude modulation (AM) can be defined as the regular (cyclic) variation in noise level, usually at blade passing frequency, which exhibits a change in the noise character of the wind farm noise as the decibel level rises and falls.
Work Package Title: Study of Noise and Amplitude Modulation Complaints Received by Local Planning Authorities in England
Trevor Sherman analyses responses from a survey of local planning authorities (LPAs) to determine the extent of the wind turbine noise problem across England.
The objectives of INWG WP 3.1 are defined as:
- To quantify the noise and excess amplitude modulation (EAM) complaints received by LPAs in the last five years;
- To establish how LPAs investigate and mitigate for noise and EAM nuisance and through this determine the guidance they need;
- To assess the frustrations and ideas coming forward from LPAs and through this determine a way forward.
Work Package Title: Excessive Amplitude Modulation, Wind Turbine Noise, Sleep and Health
Dr Christopher Hanning summarizes the effects of Excessive Amplitude Modulation (EAM) on people living close to wind turbines including annoyance, sleep disturbance and health effects through a review of the available health related literature. His report discusses ETSU’s inability to protect noise sensitive receptors from sleep disruption and therefore harm to their health and in this context to consider the contribution of EAM.
The objective of WP3.2 is defined as:
- To summarize the effects of Excessive Amplitude Modulation (EAM) on people living close to wind turbines including annoyance, sleep disturbance and health effects through a review of the available health related literature.
Work Package Title: Den Brook
Mike Hulme documents the legal, planning and technical issues surrounding the Den Brook AM planning condition (2009). This work package details the enormous effort Renewable Energy Systems (RES), the wind farm developer, has gone to over the last 8 years to ensure first that an AM planning condition is not applied, then to have the applied planning condition removed, and finally to have it sufficiently weakened presumably to ensure it prioritises development of the wind farm rather than provides intended protection against EAM.
The objective of WP4 is defined as:
- To document the legal, planning and technical aspects surrounding the Den Brook AM planning conditions.
Work Package Title: Draft AM Planning Condition
Sarah Large investigates options for the control of AM.
The objectives of WP5 are defined as:
- To conduct a review of existing or proposed methods of identifying and controlling EAM.
- To develop and propose one or more EAM control methods for further testing with the view to use as an EAM planning condition.
- To ensure that any EAM condition takes account of the psycho-acoustic response as far as practicable and account for other character features associated with AM (e.g. tonality, low frequency noise, impulsivity).
And that the final AM condition should be:
- Provided in a simple format that can be applied as a standard planning condition that is comprehendible to the lay person.
- Accompanied by relevant software or guidance notes on its application and use.
- Must be robust and must prevent AM that has been justifiably complained of and / or is deemed to constitute noise nuisance.
Work Package Title: Legal Remedies & Supplementary Paper
Richard Cowen considers the legal issues surrounding wind turbine noise nuisance.
The objectives of WP6.1 are defined as:
- To assess the legality of the Den Brook Condition relating to EAM following the judgement of the Court of Appeal;
- To assess the legal appropriateness of other remedies such as Statutory and Private Nuisance that have been recommended since that judgement or may be available to persons affected by EAM;
- To recommend the most appropriate course of action that will provide legal protection to residents hosting wind farms should EAM occur.
In the Supplementary Paper 6.1A Richard Cowen considers the legal issues for claimants relating to shell companies.
In paragraph 6.29 of WP6, it is mentioned that if a nuisance is found to exist in a hearing relating to Statutory Nuisance, a criminal offence is also committed. The implications of this have been brought to light, and clearly into focus, in the proceedings for a finding of Statutory Nuisance in respect of noise complaints resulting from the operation of the Cotton Farm Wind Farm in Cambridgeshire. Those proceedings are still ongoing but an update will be required to this part of WP6 when the position becomes clear following their completion.
Work Package Title: Control of AM noise without an AM planning condition using Statutory Nuisance
Bev Gray reviews from a community perspective the practical experiences and causal effects of Statutory Nuisance (SN) laws when used as a means of protection from Excessive Amplitude Modulation (EAM). This work package compliments WP6.1 – legal review by Richard Cowen.
The objectives of WP6.2 are defined as:
- Review EAM noise nuisance complaints procedures and the difficulties of applying Statutory Nuisance by local authority officers.
- Proposals to ensure a more effective method of EAM control than the existing statutory nuisance.
Work Package 7
Work Package Title: Test of the IoA AMWG methodologies
Sarah Large will test the effectiveness of the AM rating methodology currently proposed by the IoA AM Working Group (AMWG) in their consultation document (Irvine April 2015). The AMWG was set up with the aim of reviewing existing evidence on AM and producing guidance on the assessment of AM. Whilst originally the goal of the group was clearly to provide a means to assess AM, which could then be included in a ‘standard’ form of planning condition for wind energy development, recent publications released by the IoA AMWG confirm that their scope is now limited to providing a metric for quantifying AM.
Work Package Title: Review of IoA AM Study and Methodology
Richard Cox reviews the activities of the Institute of Acoustics and its Noise Working Groups with respect to wind turbine noise amplitude modulation.
Work Package Title: Review of WSP/Parsons Brinckerhoff and Institute of Acoustics Amplitude Modulation Studies (dated 12 January 2017)
Richard Cox (with contributions from 9 others) reviews the wind turbine amplitude modulation reports of WSP/Parsons Brinckerhoff and the Institute of Acoustics amplitude modulation working group and then makes appropriate recommendations to government.
This document was presented to Jesse Norman MP, Parliamentary Under Secretary of State, Minister for Business and Industry, at a meeting with INWG representatives on 1st March 2017.
The report makes the following recommendations to Government Ministers:
- The AMWG and WSP/PB untested and unproven proposals for the measurement and control of AM should be rejected by government unless proven to be a reliable and effective solution to protect wind turbine neighbours;
- That Government introduces regulation to the wind industry requiring licencing of individual wind turbine or wind farm sites in a similar manner to other polluting industries.
The report also repeated and reinforced the INWG key recommendations from Work Package 10 dated November 2015.
The appendices to Work Package 8.1 are published separately.
Work Package Title: The Cotton Farm Monitor Experience
Bev Gray provides a review of a rural community’s experience in setting up and carrying out long term continuous noise monitoring and recording of wind farm noise.
The objective of WP9 is defined as:
• To document the experience of fighting a wind farm application and the decision to carry out long term noise monitoring by the local community to prove the existence and frequency of noise emanating from a newly built wind farm.
Work Package Title: Report Summary
Richard Cox summarises the Study Work Packages and brings forward the INWG’s key finding and recommendations.