CHAPTER 2

NOISE AND ANY ADVERSE HEALTH EFFECTS

Wind farm noise

2.1        Wind turbines convert wind energy to rotational energy and acoustic energy. The rotational energy produces electricity; the acoustic energy produces sound.

2.2        According to a report commissioned by the Clean Energy Council (the Sonus Report), which was submitted in evidence by the Council, and which was quoted by a number of witnesses, 'the acoustic energy generated by a wind turbine is of a similar order to that produced by a truck engine, a tractor, a large forklift or a range of typical earthmoving equipment. However, a wind turbine is a stationary source that operates in conjunction with other turbines in a generally windy environment, is located high above the ground and has different noise characteristics compared to these other noise sources'.[1]

2.3        Sound attenuates with distance, in general at a rate of 6 dB per doubling of distance. A number of factors influence the attenuation of sound, including terrain, vegetation, buildings and atmospheric conditions. The pitch (frequency) of the sound is also a factor. Low frequency sound attenuates at about half the rate as higher frequencies.[2] Noise standards in different jurisdictions in Australia and overseas take these factors into account in setting minimum distances between wind farms and dwellings.

2.4        The Sonus Report identified two sources of noise from a turbine – mechanical noise from the gear box and generator and aerodynamic noise. The aerodynamic noise, which is produced by the rotation of the turbine blades through the air, dominates.[3]

2.5        Witnesses described this aerodynamic noise in different ways, but most agreed that it is characterised by 'swish' and 'thump'. A British acoustic consultant, Mr Dick Bowdler, who has specialised in wind farm noise since 1993, submitted that the dominant characteristic of turbine noise that cannot be mitigated completely is amplitude modulation or AM. He provided the following information:

All modern large turbines exhibit AM and this has been explained by Oerlemans ... when the observer is close to the turbines and at greater distances in specific directions. The effect is merely the directivity and Doppler amplification of the noise. Upwind or downwind of the turbine this reduces quite rapidly with distance but Oerlemans has shown that it can project over longer distances in the cross wind directions. This is what is often called “swish”. If it is present in the noise at a receiver, the noise is perceived as being more annoying than if the noise has no modulation. It can become impossible not to notice the noise.[4]

2.6        Mr Bowdler informed the Committee that there appears also to be another type of AM:

It is sometimes called thump on the basis that some people including Salford University, van den Berg and me have suggested that it has a faster rise time than the swish described by Oerlemans ... It is also frequently perceived indoors which may be understandable if it is around the same frequency as the weak resonance region of double glazing units.[5]

2.7        A report by Delta, a Danish acoustics consultancy, for the Danish Energy Authority found that the lower frequencies dominate indoors 'as here the changes in the lower part of the spectra will be perceived to a higher degree than outdoors'.[6]

2.8        Less technical descriptions of the sound made by wind turbines varied from 'like a jet that never lands' to 'the noise made by a distant refrigerator'.

2.9        The noise produced by a wind farm may be different from that produced from individual turbines. Under steady wind conditions the noise from a wind farm may be exacerbated by synchrony among noises from more than one turbine. It has been suggested that if the dominant frequencies of different turbines vary by small amounts, an audible beat or dissonance may be heard.[7]

2.10      Wind turbines produce sound at a range of frequencies, from high to very low, including very low frequencies that are not normally audible to the human ear. These low frequencies are called infrasound. It was asserted that infrasound is not a significant feature of modern wind farms[8] but, according to Mr William Huson, an acoustics consultant, that assertion is not true,[9] and an official UK Advisory Group has found that infrasound is present.[10]

2.11      An Italian study found that infrasound from wind turbines may be detected at some distance from the turbines:

Among these [low frequencies], the most energetic is that at frequency 1.7 Hz which, under particular conditions (i.e., low cultural noise and strong wind) can be clearly observed at epicentral distances as large as 11 km. At this particular frequency, waves depict a complicate pattern of attenuation with distance, characterised by a marked decrease in the decay rate for ranges larger than 2500–3000 m.[11]

2.12      There was evidence that the design of modern turbines has resulted in less noise. While this may be true of turbines of similar capacities, there was evidence that the noise from a typical 0.5 MW turbine in 1996 was 100 dB(A), but that a typical 3MW turbine in 2011 produces 107 dB(A).[12] (Planned industrial wind farms in Australia, for example, the Moorabool wind farm, usually incorporate turbines of this capacity.)

2.13      Dr Alan Watts of the Carcoar Medical Centre submitted that :

Small increases in the diameter of a wind turbine's rotor area can lead to substantial increases in the effects of wind speed (because the area of a circle is (πr2) which thus results in an exponential increase in the production of sound waves (specifically infrasound or low frequency vibration). This is a problem with modern wind turbines where increasing size will potentially cause intensifying infrasound related health problems.[13]

2.14      A great deal of information was submitted about the effects of the noise produced by wind farms on individuals living in close proximity to them. A number of persons who were living within one kilometre or so of functioning wind farms submitted that their quality of life had been diminished. The Committee also received many accounts of adverse health effects in submissions and during its hearings. A significant number of submissions gave actual accounts of serious symptoms of ill health that witnesses said occurred after wind turbines began operating in close proximity to their residences.

2.15      However, Dr Mark Diesendorf, Deputy Director of the Institute of Environmental Studies, University of NSW, informed the committee that noise from wind farms is rarely an issue beyond 500 metres:

Noise is rarely a problem beyond a distance of 500 m and very few dwellings in Australia are within 400 m of a large wind turbine. Licence conditions for wind farms should, and mostly do, set objective, measurable noise limits. On the rare occasions where these limits are surpassed, for example, resulting from a faulty turbine or sound propagation resulting from peculiar topography, affected residents can have the problem fixed or the offending turbine shut down.[14]

2.16      The Committee did not receive any evidence from people who are living near the turbines and who are receiving recompense for the use of their land. The reasons for this are unclear. Several witnesses claimed that the host landholders are subject to 'gag' orders under the terms of their contracts with the developers. This was denied by the industry, although the industry stated that some commercial confidentiality clauses are included in contracts during the planning stages. Mr Geiger, Managing Director, WestWind Energy, stated that:

... our landholders are not subject to any gag orders with regard to health or any other impacts.[15]

2.17      The Victorian Government Planning Panel that inquired into the Moorabool Wind Energy Facility found that noise limits and limits on shadow flicker do not necessarily apply to host dwellings because 'such dwellings are effectively part of the wind farm'.[16]

Quality of life issues

2.18      Wind farms introduce into rural environments sounds, and levels of sound, that had not been present in the environment before the advent of the wind farms. These sounds may be perceived as intrusive and detrimental to the amenity of people affected by them. The Sustainable Energy Association of Australia stated that '...much of the significance of this issue...appears to arise from a change in the noise environment and this change has had some amenity impact'.[17] However, the Association stated that noise concerns are able to be met under existing guidelines and regulatory regimes.[18]

2.19      CSIRO informed the committee that:

... changes in noise inputs in a residential landscape are important even if they are not linked with identifiable health impacts. The perceived tranquillity of the local landscape for the local population is often highly valued. The introduction of a new sound, from which the surrounding residents receive no direct benefit, heavily impacts on their acceptance and support of the technology.[19]

2.20      In Mr Bowdler's opinion, the major factor that determines the impact of a new noise source is perception. Referring to the UK experience with wind farms Mr Bowdler stated that if people feel that they are  not being treated fairly, they will perceive, rightly or wrongly , that:

Their lives will be blighted by these developments

They will gain no benefit

They pay subsidies in the form of Tax

They pay more for electricity

Developers make all the money.[20]

2.21      Mr Bowdler concluded that 'The result is that that people believe that government and developers are covering something up. This merely reinforces the views of those people who already believe that there is something mysterious about wind farm noise'.[21]

2.22      One witness, who has 30 wind turbines within two kilometres of his home, the nearest 600 metres away, stated that:

The types of noises that we experience depend on wind direction. The noises range from a doof-doof noise, like you would hear from a subwoofer at a party down the street, to a constant jet rumble. We can also hear the generator noise, like a fridge when it fires up—that electrical sound—and at times a whooshing noise, like a stick being swung through the air quickly. These noises are not just for a minute or two but can go on all night, not to mention the day. On average, we would say that we have interrupted sleep at least three to four nights a week and on some occasions up to five ..., this has been since they [the turbines] have been commissioned. I have tried to escape from the continuous noise by relocating to one of the four bedrooms in the house, only to be awakened by the noise from other turbines. My wife actually goes to sleep with ear plugs in. This continuous interruption to and lack of sleep has enormous impact on our lives, our business and our future. Last week the noise could be heard over the television inside the house.[22]

2.23      Mr Dean, a farmer whose properties are near the Waubra Wind Farm,  informed the Committee that his family was so badly affected that they had to move to Ballarat, but that he had to return to his farm from time to time:

I tried to stay away from the farm as much as I could but I had to make a dollar somehow so we went back. Every time I went back if the turbines were going it would probably take me 10 days to get over it.[23]

Noise standards

2.24      Governments attempt to meet noise problems associated with wind farms by applying standards that are intended to ensure that the sound levels do not exceed certain limits and that the amenity of the people living in proximity to the wind farms is not unnecessarily adversely affected. The standards apply in the development planning process and in compliance measures on completion of the turbines.

2.25      The Clean Energy Council stated that the standards applied in Australia are among the most stringent in the world[24] but, as the Sonus report commented:

Regardless of the stringency of the base noise level or the available masking effect of the ambient environment, wind farm standards and guidelines are not established to ensure inaudibility.[25]

2.26      The setting of wind farm noise standards is a matter for the state or local government authorities. Different jurisdictions apply different standards e.g. Government of South Australia Wind Farms Environmental Noise Guidelines July 2009, New Zealand Standard NZS 6808: 2010 Acoustics – Wind Farm Noise. The different standards do not vary greatly from one another. Base noise levels (generally 35dB(A)) and background noise limit margins (5 dB(A)) are specified. The Australian Standard 4959 – 2010 Acoustics – Measurement, prediction and assessment of noise from wind turbine generators does not appear to be applied in any jurisdiction, although the EPHC draft guidelines suggest that it should form the base for any noise assessment.[26]

2.27      Sonus reports that the standards and guidelines include the following:

• Objective standards that provide a base noise limit and a background noise related limit...;[27]
• A background noise and wind speed measurement procedure to determine the applicable background noise related limits at each dwelling;
• A noise level prediction methodology to enable a comparison of the predicted noise level from the wind farm against the noise limits at each dwelling;
• The required adjustments to the predicted noise levels to account for any special audible characteristics of the wind farm noise;
• A compliance checking procedure to confirm the operational wind farm achieves the predicted noise levels at each dwelling.[28]

2.28      There was evidence that the assessment methodologies contained in the standards that applied to some wind farm developments are now out of date. The Pyrenees Shires submitted in relation to the NZ6808:1998 standard used in Victoria in relation to one wind farm that:

... the recent experience with the Waubra wind farm, where 32 noise complaints have been received by Council and DPCD since the first turbine was commissioned 18 months ago shows that this noise standard is in urgent need of replacement.[29]

2.29      The Committee is aware in this regard that the Victorian Wind energy facility provisions were amended in March 2011 to ensure that the noise impacts of wind turbines will in future be in accordance with the New Zealand Standard NZS6808:2010, Acoustics – Wind Farm Noise.[30]

2.30      Local councils submitted that they are significantly under-resourced to deal with wind farm complaints and to oversee that wind farms are complying with noise standards. The Committee is aware of the avenues of appeal against development application approvals by state or local government.  Planning panels, tribunals and courts are interested in ensuring that the various conditions, including the noise standards, have been properly met. However, the question arises whether the standards are appropriate for their intended outcomes. The standards are not without their critics.

2.31      The Committee received a number of submissions that pertained to concerns regarding noise standards. Several submissions relayed concerns that relevant noise standards may not sufficiently address concerns regarding any adverse health effects. Noise Measurement Services in a report commissioned by Mr and Mrs Dean stated, in relation to the Waubra Wind Farm:

 It is concluded that wind farm noise prediction, as implemented under NZS6808 (the New Zealand wind farm standard) is not adequate in assessing potential adverse effect and implementation of the standard does not and will not provide an acceptable level of amenity. Application of the standard does not provide a conservative assessment of sound levels that may be experienced under different meteorological conditions.[31]

Noise measurement

2.32      The measurement of noise as used in the Standards is dB(A). This measure was explained as being appropriate because it simulates human hearing.[32] Dr Warwick Williams, a Senior Research Engineer at the National Acoustic Laboratories, explained that the A-weighting heavily discounts the low frequencies and the very high frequencies.[33] A-weighting discounts infrasound as it is below the level of human hearing.

2.33      Many persons who complain of the noise produced by wind farms refer to noise that lies within the low frequency range, and to infrasound (sound of less than 20 hertz). As discussed earlier, the 'thump' which apparently is produced by wind turbines and which causes distress to some people is a low frequency sound. According to the Sonus report, over large distances, whilst the absolute level of sound in all frequencies declines, the relative level of low frequency noise increases compared with mid and high frequencies. The Sonus report states that low frequency sound can be easily measured, and 'the C-weighting network (dB(C)) has been developed to determine the human perception and annoyance due to noise that lies within the low frequency range'.[34]

2.34      Mr Huson submitted that neither the C-weighting nor the A-weighting is appropriate for the measurement of very low frequencies:

If we were to investigate lower frequency sound levels from wind farms we cannot use the C-weighting or the A-weighting since these attenuate low frequency sound <20 Hz significantly. The G-weighting is designed to quantify infrasound below 20 Hz.[35]

2.35      Dr Geoff Leventhall, a British acoustics consultant, informed the committee that:

...as environmental noise control criteria are A-weighted, they tend to under-rate potentially problematic low frequency environmental noise. This has led low frequency problems to be left to continue, whilst higher frequency problems are fixed more quickly. As a result, where genuine low frequency noise problems have occurred, their continuance leads to the development of undue stress in those affected. There is also a body of very stressful, unsolvable noise problems, described as “low frequency” by those affected, where detailed investigations cannot discover a specific noise source.[36]

2.36      The Noise Management Services report commissioned by Mr and Mrs Dean on the noise impact of Waubra Wind Farm suggested that:

There are many possible ways that low frequency sounds may influence the ear at levels that are unrelated to hearing sensitivity. As some structures of the ear respond to low frequency sound at levels below those that are heard, the practice of A-weighting (or G-weighting) sound measurements grossly underestimates the possible influence of these sounds on the physiology of the ear. The high infrasound component of wind turbine noise may account for high annoyance ratings, sleep disturbance and reduced quality of life for those living near wind turbines.[37]

2.37      A number of witnesses informed the committee that the low-frequency noise from a wind farm was too little to adversely affect nearby residents. Mr Matthew Rebbeck, Technical Director, RES Australia Pty Ltd, informed the committee that:

The dBG levels in the Adelaide CBD are, for example, 76 decibels; at a local beach, 75 decibels; a gas-fired power station nearby, 74 decibels; at a cliff face, 69 decibels; and then we are down to the wind farms, 67 and 63 decibels, at 185 and 200 metres downwind of the closest turbine. Of course, the nearest neighbours are normally much further away than that.[38]

2.38      The EPHC draft guidelines state that an assessment of low-frequency noise is not required as part of the pre-construction phase or post-construction monitoring phase for wind farms. This is because 'low frequency noise and infrasound levels generated by wind farms are normally at levels that are well below the high levels required to cause any health effects'.[39]

2.39      This statement appears to have been based on the findings of a Sonus report, Infrasound Measurements from Wind Farms and Other Sources,[40] which was commissioned by Origin Energy. Mr Huson submitted that he had reviewed the data presented in that report and had found that it reached very questionable conclusions.[41] Mr Dean informed the Committee that he had measured sound at the beach and between turbines 300 metres away with an imported SVAN 959 machine and concluded:

It is all high-frequency noise at the beach and it is all infrasound, below 20 hertz, at Waubra between the turbines. That is low-frequency infrasound that our bodies cannot bear.[42]

2.40      Pacific Hydro submitted that infrasound emissions from operational wind farms are significantly below recognised perception thresholds of 85dB(G)[43] and Dr Diesendorf submitted that:

Infra-sound used to be a problem with some of the early wind turbines in Europe. However, according to recent European studies, modern wind turbines emit generally very low levels of infra-sound, virtually undetectable at a range of 500 m and much less than comes from motor vehicles on nearby roads. Although there have been several studies, there is no scientific evidence that infra-sound from wind turbines located at a distance greater than 500 m is a health hazard.[44]

2.41      The Committee was informed that Denmark 'the home of wind power' has flagged regulation of infrasound at wind farms and that Japan last year started a four-year study in the effects of infrasound from wind farms. The British Government also has announced that it has begun 'to review the issues that which often cause concern to local communities—such as the assessment of noise and the flickering effect when blades rotate'. [45]

Committee view

2.42      Although infrasound from modern turbines may be less than from older models, it is nevertheless present. The relevant standards applied in Australia rely only on the dB(A) measurement which does not take infrasound and low frequencies fully into account. If the Australian standards were to include an appropriate measurement of low frequency noise, including infrasound and vibration, governments and developers may find that at least some of the opposition to wind farms might be alleviated. In that context Mr Huson commented that:

In the absence of applicable research it may be appropriate to set target infrasound noise limits indoors, that are easily measured, at 75 dB(G). Wind farm proponents regularly espouse that modern wind farms do not cause such sound levels so there should be no complaints from that quarter if such [a] precautionary target were to be set.[46]

2.43      Similarly, the Danish Delta report suggested that:

For projects where outside noise levels are close to the existing noise limits for wind turbines it will be good practice to perform calculations of the indoor low frequency noise impact. This will ensure that appropriate low frequency noise levels are met and hopefully contribute to minimize groundless anxiety in cases with no low frequency impact.[47]

Recommendation 1

2.44             The Committee considers that the noise standards adopted by the states and territories for the planning and operation of rural wind farms should include appropriate measures to calculate the impact of low frequency noise and vibrations indoors at impacted dwellings.

Compliance with Noise Standards

2.45      The Victorian Minister for Planning suggested that non-compliance with standards may be a primary issue for sites where communities report negative health impacts and that authorities need to ensure there is thorough assessment against the appropriate standards.[48]

2.46      Development licences for wind farms generally require developers to monitor and report on their compliance with approved noise standards. This report may be made to a government agency or may at least be made available for audit by government. However, some witnesses suggested that compliance was not being adequately monitored.

2.47      Once wind farms begin to operate, different jurisdictions take somewhat different approaches to enforcing compliance with noise standards.

2.48      In South Australia one of the requirements of a wind farm licence is that the operator complies with a Safety, Reliability, Maintenance and Technical Management Plan which covers noise. AGL informed the Committee that the company's plan is regularly audited by the Essential Services Commission of South Australia.[49]In New South Wales operators are required to establish procedures for dealing with complaints. It is not clear, however, whether the procedures are satisfactory. The NSW Legislative Council Committee that inquired into rural wind farms reported that noise pollution, including from electricity generation, is covered by the Protection of the Environment Operations Act 1997, but that wind power generation is not covered. That Committee reported that it was concerned about:

... the reasons why wind power is excluded from being a scheduled activity when all other types of electricity generation (other than solar power) are included. Reasons for this are ambiguous and have resulted in the blurring of what was initially a very clear process for addressing noise pollution in NSW.[50]

2.49      In Victoria, there is some dispute about which level of government is responsible for operators' compliance with the conditions. Mr Chris Hall, the Senior Town Planner with the Pyrenees Shire Council, informed the Committee that:

The current position of the state government in its policy guidelines is that councils are responsible for enforcing and administering all planning permits regardless of the 30-megawatt demarcation or whether or not they were called in under the section 96 call-in powers under the Planning and Environment Act. We have had legal opinions—one from a QC and the other from a well-respected planning lawyer—to the contrary that unequivocally back the council position that, in situations where those applications are called in, the minister actually becomes the responsible authority for administering and enforcing the permit.[51]

2.50      Local governments stated that they lack the resources and the expertise to ensure that wind farms comply with development approvals. Councils also expressed concern with the suggestion that they should be required to enforce compliance with plans for which they have had no responsibility.[52]

2.51      In all jurisdictions, it seems that complaints about excessive noise are made to the wind farm operators in the first instance.     

2.52      The wind farm operator Pacific Hydro informed the committee that it receives few complaints[53] and that the complaints it receives are taken seriously. Mr Rebbeck of RES Australia informed the Committee that his company talks to the landholders concerned and does any further noise measurements that are required. He stated that:

We invariably find that the reason for the valid noise complaints is that there is a mechanical failure with the closest turbine or a nearby turbine, so you are getting a tonal noise from that turbine. Tonal noise is picked up very well by the human ear. That is above and beyond your planning limits. You are effectively exceeding your planning limits. Once you fix that turbine and you correct that problem with the turbine and the turbines are operating within their planning guidelines, we do not have any noise complaints.[54]

2.53      Addressing complaints to the operators may however lead to perceptions that the complaints are not taken seriously or are unreasonably dismissed as invalid. In relation to the Waubra wind farm, Mr Dean claimed that it was only after 12 months of operation that the company started to register complaints.[55] Mr Dean submitted that the operator designs and writes its own noise management plan and that does not work because the operator 'remains in control of everything'. The operator can thus assert that there is no substance to a complaint.[56] The operator, Acciona, disputed Mr Dean's assertion.[57]

2.54      Operators' reporting requirements also may be an issue. Mr Hall stated that:

With respect to post-commissioning noise compliance monitoring of developments, under the condition requirements of many permits, there has not been a requirement for testing data to be provided until 12 months after the commissioning of the last turbine. That is resulting in 20-plus month delays in the data being made available to the public and obviously in the department being able to investigate any breaches, such as in the Waubra situation. We had to wait over 14 months before we could find out some of the issues that have arisen there.[58]

An Independent arbitrator?

2.55      Mr Dean submitted that:

It seems very strange to me that there is not an independent moderator for this situation, when we say there is a problem and they (Acciona) say there is no problem. After all, it is in the company's interests for there not to be a problem, so they take control of as much as they can and use their influence to get the outcome they want, it is ridiculous there is no third, completely independent party to resolve the situation.[59]

2.56      In response to a question from the Committee, witnesses representing the wind farm operators stated that they would be prepared to report quarterly to government on the complaints that they receive and stated that in some Australian jurisdictions this may already be required.[60]

Committee view

2.57      The Committee considers that if they do not already do so the responsible planning approval authorities should ensure that complaints about noise from wind farms are dealt with as soon as the complaint is received. This process should involve an impartial arbitrator. Additionally, there appears to be some confusion about the responsibility for investigating complaints between the different levels of government. If this confusion were resolved investigation of breaches of the noise standards would be facilitated.

Recommendation 2

2.58             The Committee recommends that the responsible authorities should ensure that complaints are dealt with expeditiously and that the complaints processes should involve an independent arbitrator. State and local government agencies responsible for ensuring compliance with planning permissions should be adequately resourced for this activity.

Setbacks

2.59      In Australia buffer zones exist between wind farms and residences. These zones are determined by the attenuation of sound from the wind turbines and require that measurements are made at residences that fall within a sound 'contour' of the proposed wind farm. In theory the noise from wind turbines should attenuate to the legislated levels within a set distance. However, the noise perceived at residences will be determined by a number of other factors including the size, number and mechanics of the turbines, topography and prevailing winds.

2.60      It has been suggested that the establishment of prescribed buffer zones (setbacks) would be preferable to a noise-based setback to help preserve the amenity of residents from the noise and flicker effects created by wind farms. Mr Peter Wingett, representing the Prom Coast Guardians Inc., stated that:

Adequate mandatory setbacks and rigorous enforcement of maximum noise standards would reduce the adverse impacts on properties neighbouring wind farms. A minimum setback of two kilometres or 20 times the maximum height, including the blades, of wind turbines to the nearest dwelling would be a desirable first step.[61]

2.61      The State Government of Victoria has recently amended the state's wind energy facility provisions to mandate that applications for the establishment of wind farms should include a plan showing all dwellings within two kilometres of a proposed turbine.[62] (The amendment also requires, among other things, that the applications include a concept plan of associated transmission infrastructure, electricity utility works and access road options.)

2.62      It is not known how this requirement will work in practice and therefore whether it will necessarily lead to a two kilometre buffer zone. The Victorian Planning and Environment Law Association suggested that because it is one of the assessment matters that need to be brought to the attention of the planning application that it will form part of the assessment criteria from now on.[63]

2.63      Wind farm developers and some other witnesses considered that prescribed buffer zones, such as a two kilometre setback, are not appropriate. The Clean Energy Council argued that because every wind farm and every community is different, because there are different geography and topography, and different prevailing winds, each application should be assessed on audible noise.[64] The Sustainable Energy Association of Australia stated that:

... a buffer zone should be entirely dependent on the actual physical characteristics of the wind farm, such as the number and size of turbines, its siting and location, and the acoustic factors in the area—these are used by the wind industry to determine what the zone should be. A blanket buffer zone does not face the realities of what is actually there. So we perfectly accept that there is a noise place and a noise amenity issue, but we do not believe a blanket zone is best practice either here in Australia or globally.[65]

2.64      Buffer zones may also be needed to ensure that residences are not affected by shadow flicker. Shadow flicker is caused by rotation of the turbine blades casting intermittent shadows. This gives the appearance of flickering and the effect can be visually annoying. The standards applied in the different Australian jurisdictions seek to limit shadow flicker for nearby residences. Mr Geiger stated that:

... if we follow the New Zealand standard on noise, then the setbacks due to complying with the noise standards are generally greater than the setbacks required to avoid shadow flicker. So that is an issue that we do not expect to occur in Australia. With our German operations, the noise limits are much less stringent. We go as close as 300 metres to the closest house with some of our installations there. At that distance shadow flicker would be an issue.[66]

2.65      Mr Burn from WestWind Energy stated that standards applied in at least some Australian jurisdictions specify that no more than 30 hours of shadow flicker per year should be experienced by affected dwellings.[67]

2.66      Setback requirements to adequately prevent any adverse health effects have been rigorously debated. While the wind industry is against setback distances, a large number of submissions to the inquiry from researchers and concerned community members called for setback distances ranging from 2 km to 10 km.

Committee comment

2.67      A difficulty with a prescribed setback distance is that, in terms of noise and shadow flicker, the distance may either be too great or too little. If the setback is too great then this could limit the industry and possibly affect the amount of renewable power generation in Australia. If the distance were too little, residents affected adversely would not have any redress.

2.68      The Committee considers that the application of scientific measurements for sound and for shadow flicker to alleviate problems for wind farm neighbours may be preferable to prescribed setbacks. Prescribed setbacks are arbitrary and may be too great or too small. In addition, there is also some dispute about the noise standards set by governments and the noise measurements used. The matter is not necessarily settled. The Committee suggests that further consideration be given to the development of policy on separation criteria between residences and wind farm facilities.

Recommendation 3

2.69      The Committee recommends that further consideration be given to the development of policy on separation criteria between residences and wind farm facilities.

Wind Farms and Health

2.70      Much of the evidence that the Committee received in relation to claimed adverse health effects of wind turbines focussed on 'Wind Turbine Syndrome' (WTS). This term was first used by Dr Nina Pierpont, an American medical practitioner, to describe a group of symptoms suffered by some people who have lived in close proximity to wind farms. The core symptoms of this condition as described by Dr Pierpont are as follows:

Sleep disturbance

Headache

Visceral vibratory vestibular disturbance

Dizziness, vertigo, unsteadiness

Tinnitus

Ear pressure or pain

External auditory canal sensation

Memory and concentration deficits

Irritability, anger

Fatigue, loss of motivation.[68]

2.71      A number of witnesses stated that they had suffered some or all of the above symptoms and attributed their ill health to the noise and in particular the low frequency noise and infrasound[69] from wind turbines.[70] Some stated that they had been so badly affected that they had to leave their homes at considerable cost and inconvenience.[71]

2.72      Professor Simon Chapman, Expert Adviser, Climate and Health Alliance and Professor, Public Health, University of Sydney criticised Dr Pierpont's work on a number of grounds. He considered that the sample used was too small and unrepresentative in terms of the medical history of the respondents to the survey; that the respondents had not been medically examined; that Dr Pierpont's book had not been peer-reviewed; and that Dr Pierpont did not have any other publications in the field.[72]

2.73      Mr Briddy, a farmer from Lexton, Victoria, stated that although his homestead is 5.5 kilometres from the Waubra wind farm, due to the topography he has problems with the vibrations from the turbines, including having trouble sleeping.[73]

2.74      Mr Stepnell, whose home was 900 metres from wind turbines at Waubra, informed the Committee that after about six months the turbines began to affect his health:

It started with the headaches and the tingling in the head and then eventually the sleep problems—waking up at two to three in the morning and not being able to go back to sleep. It was just every night, maybe until five or six nights of absolute fatigue set in and then you would sleep. It took that long to do it and then away you go again. Then eventually I had heart palpitations, which were a massive concern.[74]

2.75      Mr Stepnell and his wife consulted a medical practitioner who offered to prescribe anti-depressants, but as they were unwilling to turn to medication to live in their home, they bought a house in Ballarat, which was a huge financial cost.[75]

2.76      Mrs Kearns, who lives on a 16 hectare property in close proximity to the approved Moorabool wind energy facility, stated as follows:

My brief anecdotal evidence re health effects is as follows: on 4 January this year, my husband and I decided to visit Waubra to view the wind farm. It was a cool, rather overcast day, not too windy. We spent over one hour and then went home. At 2 o’clock the next morning, I woke with severe chest pain. I had enough sense to take my blood pressure reading. I have no history of hypertension. I am very healthy normally. My blood pressure was 211 over 103, so health professionals know that that is far too high. I should have stroked out. I called the ambulance and I was transported to hospital and admitted to ICU for 24 hours. Further tests disproved any cardiac condition, so the diagnosis was probably stress, just from the worry.[76]

2.77      Dr Sarah Laurie, Medical Director of the Waubra Foundation, submitted details of her 'field observations' of more than 60 affected persons in three states. These persons described that they suffered from the symptoms identified by Dr Pierpont. Many of the individuals interviewed had never heard of Dr Pierpont or WTS. Dr Laurie informed the Committee that her findings were consistent with those of a UK and also an Australian rural general practitioner who noticed that some of their patients were reporting those symptoms after wind farms began operating in their vicinity.[77]

2.78      Dr Laurie also submitted that elevated blood pressure and associated heart problems were occurring among people affected by wind turbines.[78] Professor Gary Wittert, a senior consultant endocrinologist at Royal Adelaide Hospital, who had access to the blood pressure readings of those involved, stated that 'no assertion could be made that there was any relationship between mean overnight turbine power and elevations of blood pressure'.[79]  

2.79      Most witnesses, including those representing wind farm developers,[80] accepted that some people in the vicinity of wind farms have become ill, but suggested, firstly, that these peoples' problems were not caused by the noise from farms per se and, secondly, that work had not been done to indicate that the incidence of the reported symptoms among that group of people was higher than in the rural population generally.  

2.80      Mr Rebbeck of RES Australia, for example, informed the committee that 'nobody disagrees that high levels of low-frequency noise cause health impacts'.[81] He referred to research involving fighter pilots and truck drivers.

2.81      A Portuguese study reported that:

 ... there are acoustical events that are not necessarily processed by the auditory system, but that nevertheless cause harm. Infrasound and low frequency noise (ILFN, <500Hz) are acoustical phenomena that can impact the human body causing irreversible organic damage to the organism, but that do not cause classical hearing impairment. Acoustical environments are normally composed of all types of acoustical events: those that are processed by the auditory system, and those that are not. [82]

2.82      Mr Bowdler agreed that some people who have lived close to wind turbines have become ill, but he did not consider that this was caused by any peculiarity of the sound generated by wind turbines. Mr Bowdler submitted that most of the subjects in Dr Pierpont's investigation had a genuine grievance related simply to the loudness of the noise. He observed that half were less than 750 metres away from a turbine and the nearest 350 metres.[83]

2.83      Dr Leventhall submitted that the hypotheses put forward by Dr Pierpont lack credibility and do not appear to have any scientific basis. He submitted that:

The so called 'wind turbine syndrome' cannot be distinguished from the stress effects from a persistent and unwanted sound. These are experienced by a small proportion of the population and have been well known for some time.[84]

2.84      Dr Leventhall has also written that he is 'happy to accept these symptoms, as they have been known to me for many years as the symptoms of extreme psychological stress from environmental noise, particularly low frequency noise. The symptoms have been published before ...'[85] He also submitted that:

Once antagonisms have been developed, even the slightest perception of a noise may lead to stress and, in its turn, long term stress may lead to somatic effects. However, this is not a function of the characteristics of the noise alone, but of the noise and listener in combination.[86]

2.85      Professor Seligman informed the Committee that:

From the engineering and physiological perspectives, there is no mechanism for consistent adverse effects of noise from wind farms beyond the distance at which the noise falls below background levels. This is typically a few hundred metres for modern equipment. However it is accepted that under some atmospheric conditions, wind farms are audible at a distance. Salt states that his study “raises the POSSIBILTY that the dislike / disturbance of individuals by wind turbine noise may be related to the long‐term stimulation of the outer hair cells with infrasound.” However the atmospheric effect mentioned above is exceptional and not long‐term.[87]

2.86      Dr Williams suggested that the noise in itself may not be the only factor in people reporting adverse effects from wind farms. He stated that:

In some cases, the aspect of the noise problem is a focal point that is focusing other people's fears, apprehensions and perceptions as to maybe what wind farms are. It may not be the noise, because everything I have been able to look at basically says that, in the normal expectation of levels that you will receive, the infrasound will not have a physical effect on people's bodies.[88]

2.87      A report on a field study undertaken in the Netherlands in 2007 with 725 respondents, which was published in the Journal of the Acoustical Society of America in August 2009, concluded that:

Wind turbine sound is easily perceived and, compared with sound from other community sources, relatively annoying. Annoyance with wind turbine noise is related to a negative attitude toward the source and to noise sensitivity; in that respect it is similar to reactions to noise from other sources. This may be enhanced by the high visibility of the noise source, the swishing quality of the sound, its unpredictable occurrence, and the continuation of the sound at night.[89]

The study also found that people benefiting from the turbines are less likely to be annoyed by it.[90]

2.88      Mr Rebbeck commented that, with 150,000 wind turbines operating globally, it would seem likely that any genuine adverse health effects would have been widely researched and published by now.[91]

2.89      Many other witnesses who asserted that there are not any adverse health effects from wind farms relied on a survey of the literature published by the National Health and Medical Research Council (NHMRC) that concluded, among other things:

There are no direct pathological effects from wind farms and that any potential impact on humans can be minimised by following existing planning guidelines.[92]

2.90      Professor Anderson, the Chief Executive Officer of NHMRC, informed the Committee that:

I do want to make a point to anybody who is relying on this.

We regard this as a work in progress. We certainly do not believe that this question has been settled. That is why we are keeping it under constant review. That is why we said in our review that we believe authorities must take a precautionary approach to this. That is what we do say in medicine anyhow, but this is very important here because of the very early stage of the scientific literature. In any area we make statements on, we are robust, we are used to being criticised from all sorts of directions and we cannot be responsible for the use that others make of the literature ...[93]

2.91      The NHMRC's 'rapid review' of the evidence concluded, among other things, that '[t]here is currently no published scientific evidence to positively link wind turbines with adverse health effects'. That statement has been relied on by developers in the wind industry to suggest that Australian research had settled the question of any adverse health effects. However, as stated by Professor Anderson, the NHMRC is keeping the matter under review and on 7 June 2011 the Council held a forum in Canberra to further investigate the health impact of wind farms with a view to updating the public statement.

2.92      The NHMRC report was not the only study relied on by those who claimed that wind turbines do not adversely affect people's health. A study commissioned by American Wind Energy Association and the Canadian Wind Energy Association concluded that:

(a)        Sound from wind turbines does not pose a risk of hearing loss or any other adverse health effect in humans.

(b)        Subaudible, low frequency sound and infrasound from wind turbines do not present a risk to human health.

(c)        Some people may be annoyed at the presence of sound from wind turbines. Annoyance is not a pathological entity.

(d)        A major concern about wind turbine sound is its fluctuating nature. Some may find this sound annoying, a reaction that depends primarily on personal characteristics as opposed to the intensity of the sound level.[94]

2.93      Some witnesses queried the impartiality of this study on the grounds that it was commissioned by the wind industry.[95] While not accepting that argument in relation to that particular study or any other study the Committee acknowledges that the claim could be made against any study whether financed by the supporters or opponents of the wind industry.

2.94      Even some government studies, which may in many circumstances be considered to be independent, also may be open to criticism because governments have a vested interest in the development of the wind industry through policies intended to encourage or support generation of electricity from renewable sources.[96]

2.95      It would therefore be difficult to satisfy all those who are interested in the health effects of wind turbines that a reliable independent study could be commissioned. Nevertheless, witnesses supported the notion that thorough epidemiological studies are needed. Dr Pierpont informed the Committee that 'what are needed are clinical large-scale epidemiologic studies and lab studies'.[97] Mr Holmes a' Court, Chairman, Hepburn Wind, stated that '[a] small number of people living near a small fraction of wind farms in Australia do not currently feel that their concerns are being adequately investigated. It is in everybody's interests that these complaints are independently, rigorously and transparently investigated'.[98] Another witness, Dr Crisp, who represented Doctors for the Environment Australia questioned whether such research was worth doing given the weight of the scientific evidence and the competition for the research dollar.[99]

2.96      Recent reports of Government of Victoria Planning Panels have suggested that that government should consider commissioning independent research in health impacts associated with wind farms.[100]

2.97      A number of witnesses suggested that any adverse health effects from wind power generation should be viewed in the context of ill health caused by other forms of power generation, especially respiratory conditions associated with fossil fuel generation.[101]  Given its terms of reference the Committee has not further considered this suggestion.

Committee comment

2.98      The Committee does not doubt that some people living in close proximity to wind farms are experiencing adverse health effects, but these are not necessarily caused by the noise characteristically produced by wind turbines. However, there were suggestions, concerns and opinions expressed that infrasound produced by the turbines is a cause of adverse health symptoms similar to those described as 'Wind Turbine Syndrome' by Dr Pierpont.

2.99      Adverse health effects may be caused by wind turbines but they may be caused by factors other than noise and vibration, such as stress related to sleeplessness or perceptions of harm. There is insufficient rigorous research to know the answer.

2.100    In view of the reported cases of illness and the possible consequences that any adverse health effects may have on communities' acceptance of wind farms the Committee considers that soundly-based studies of these matters should be undertaken as a matter of priority.

Recommendation 4

2.101      The Committee recommends that the Commonwealth Government initiate as a matter of priority thorough, adequately resourced epidemiological and laboratory studies of the possible effects of wind farms on human health. This research must engage across industry and community, and include an advisory process representing the range of interests and concerns.

Recommendation 5

2.102      The Committee recommends that the NHMRC review of research should continue, with regular publication.

Recommendation 6

2.103      The Committee recommends that the National Acoustics Laboratories conduct a study and assessment of noise impacts of wind farms, including the impacts of infrasound.

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