The design and governance of wind energy projects relies on a range of standards and various compliance mechanisms to monitor and enforce those standards.
Standards are often set and maintained by the responsible authority (for example, a state planning department or environment department) and there are a variety of arrangements in place for enforcing compliance with the standards. Standards may be ‘borrowed’ from other jurisdictions (for example, Victoria uses the New Zealand Noise Standard, the NSW noise standard is based on the South Australian standard), set by the planning function or set by the state agency responsible for environmental management and regulation.
Enforcement of standards and permit conditions also varies by jurisdiction and the type of standards. Generally, there are no proactive audit regimes in place – rather, compliance relies on receiving complaints or alleged breaches of permit conditions. The pathway to make a compliance complaint or allegation again varies by jurisdiction and type of complaint – in some cases the state environmental regulator can receive and investigate noise or environmental complaints about wind farms, in other cases it may be a local council, state planning department or the relevant Australian Government Department.
It is often unclear to community members where or who they should lodge a complaint to regarding wind farm construction or operating compliance. Planning permits may not clearly state the accountability and responsibilities with regard to compliance oversight, nor may they prescribe a process for handling potential or actual non-compliance. Further, local councils and state planning functions may not have the necessary skills and expertise to handle and investigate a compliance complaint. Federal agencies, such as the Clean Energy Regulator, rely on a clear understanding of the responsible compliance authority and the authority’s advice if the Regulator is to consider acting on allegations of non-compliance or breach of a law.
Interpretation and Consistency of Standards
Borrowed standards can also be difficult to administrate or enforce if a protocol has not been developed for the local jurisdiction. For instance, the New Zealand standard has a concept of low and high amenity areas for determining the appropriate noise limits for a wind farm. Victoria’s planning scheme does not define such areas, making it difficult to interpret and apply the NZ standard ‘as is’ in the Victorian context (see Cherry Tree Wind Farm Pty Ltd vs Mitchell Shire Council – VCAT – P2910/2012).
Issues have also arisen regarding the application of tonal noise penalties provided for in the NZ standard. The application of the standard is open to interpretation in that regard, and Victoria must rely on interpretations from New Zealand court proceedings to attempt to clarify the standard. This can be a difficult matter to resolve, particularly in the event the interpretation has also been a topic of debate in the home country (see Decision of Hearing Commissioners re Palmerston North City Council v New Zealand Windfarms Ltd – November 2017).
Typical standards and permit requirements relevant to a wind farm’s development and operation can include matters such as audible noise, shadow flicker, visual amenity impacts, setback distances, environmental matters related to flora and fauna, vegetation clearance as well as noise and dust levels during construction.
Standards relating to wind farms currently vary by state. For example, the wind farm noise limit standard in Victoria and Tasmania is 40 dB(A)* measured outside the residence. South Australia varies between 35 dB(A)* and 40 dB(A)* based on the location of the wind farm, Western Australia is 35 dB(A)*, New South Wales is 35 dB(A)* and Queensland’s standard is 37 dB(A)* during the day and 35 dB(A)* during the night. The approach to measuring the noise emitted from a wind farm can also vary by project and jurisdiction which can lead to debate over the veracity of the noise assessment results.
The World Health Organization’s (WHO) latest noise guidelines recently recommended a 45 dB (Lden) limit for wind farm noise, measured outside the residence, to prevent negative effects on sleep and health. However, the report noted the lack of research or evidence available to conclusively support this new guideline limit. Previous WHO guidelines were based on an inside measurement limit of 30 dB(A), although it can be difficult and intrusive to carry out wind farm noise testing inside a residence, particularly over a long period of time.
Current noise standards therefore rely on the effects of attenuation of the noise by the residence structure and would assume that a noise level of, say, 40 dB(A) measured outside the residence should be less than 30 dB(A) measured inside, based on an expected attenuation in the order of 10-15 dB(A). This attenuation may be greater if the windows are closed and the residence is of solid construction and well insulated, however, the effective attenuation may be less if windows are open and/or construction and insulation of the residence is less robust.
Issues can also arise where a wind farm is tested for noise and the result exceeds the limit by a marginal amount, for example 40.2 dB(A) against a limit of 40 dB(A). The Commissioner’s understanding is that the 0.2 dB(A) difference would be undiscernible by the human ear and is the result of the complex mathematical calculations that assess multiple noise data points. There may be some merit in allowing for a small, reasonable tolerance level to avoid wind farm’s unnecessarily being in technical breach of compliance.
Debate continues as to whether or not a low frequency standard should also be introduced, such as a dB(C) and/or dB(G) weighting. The prevailing argument to date is that the ‘A-weighted scale’ accommodates a sufficient proxy for low frequency noise and that low frequency noise can be difficult to detect at levels that would breach threshold targets. However, based on some complaints received, the possibility remains for annoyance for some people living in proximity to a wind farm and experiencing low frequency noises or vibrations while inside their residence. More work is still required to determine whether or not the noise or vibration source in question is the wind farm or some other source. The Office’s complaint data has seen a reduction over time in complaints citing concerns about low frequency noise or vibrations.
The Independent Scientific Committee on Wind Turbines has derived a suggested wind turbine noise limit of 35 dB(A) (LA90,10min) to ensure minimal annoyance. This suggested limit approximately equates to an LA,eq,10 min of 37 dB(A) or an Lden of 43.4 dB(A).
A setback distance (also known as a ‘veto’ distance) is a default distance that, if a residence is within that specified distance from a proposed turbine, the resident can veto the turbine or come to some agreement with the wind farm developer to allow the turbine to be sited within the setback distance limit.
Setback distances from the turbine to a residence also vary across states. Victoria originally had no setback distance, then introduced a 2 km setback distance in 2011 and, subsequently, changed it to 1 km in 2015. Queensland has introduced a setback distance of 1.5 km, while the New South Wales framework is based on a merit assessment of each project against the criteria and performance standards in the framework. Western Australia is currently considering the Commissioner’s recommendation of a 1.5 km setback. Turbines can be closer to a residence than the default setback distance, however typically require an agreement to be reached between the resident property owner and the developer.
Current setback distances have been predominately set based on legacy turbine dimensions and expected outcomes from noise standards. As a rough rule of thumb, a 40 dB(A) noise contour should be just less than about one kilometre, whereas 35 dB(A) noise contour should be just less than 1.5 km. Turbines predominantly installed during this decade have typically been at tip heights in the order of 150 metres and around 2 MW to 3 MW in capacity.
New projects are now proposing turbines with tip heights in excess of 220 metres and capacity of around 5 MW per turbine. Improvements in turbine design have mitigated the noise effects and, generally speaking, the noise contours have not materially changed for these larger turbines. However, there may well be effects of increased visual amenity and shadow flicker impacts that may give rise for a need to revisit current set back distances and increase them accordingly.
While setback distances are typically based on the distance from the wind turbine to the residence, there may also be circumstances where the distance of the turbine from the neighbour’s property boundary should also be a consideration. Such circumstances could include the potential effect of wind turbines on animals such as horses, or other situations where turbines may impact neighbouring properties due to their proximity to land use activities on a property.
The British Horse Society recommends a setback distance of 200 metres from wind turbines to horses on the basis that horses can react to noise, blade rotation and shadow flicker impacts from wind turbines, as outlined in their publication Wind Turbines and Horses – Guidance for Planners and Developers (2015).
Upper Lachlan Shire’s Development Control Plan specifies that turbines shall not be located within a distance of two times the tip height of a turbine from a formed public road or a non-involved property boundary. For example, a tip height of 150 metres would require a setback of 300 metres from a road or property boundary according to these guidelines (see ‘Upper Lachlan Development Control Plan 2010’, page 93).
There may be other sources of noise as a result of the wind farm’s operation, in particular noise that would emanate from the wind farm’s electrical infrastructure, including power substations, transformers and back-up generators. The impact of such noise sources should be assessed during the design phase and tested for compliance during any post-construction noise testing.
Electrical infrastructure required for the wind farm, such as transmission lines, may also cause a change in visual amenity for community members. Consideration should be given for those impacts and setback distances as they may also be appropriate to mitigate visual amenity loss and noise issues arising from the infrastructure.
Harmonisation of Standards
The opportunity exists for a clearer framework of standard setting and enforcement of standards, whereby there is independence in the setting and enforcement of standards from the planning function. Such independence allows for increased community confidence in the objectivity of setting standards and assessing compliance. It also allows the relevant independent agency to acquire and maintain the appropriate skills and expertise to fulfil its standards and compliance responsibilities.
The opportunity also exists for increased harmonisation of key standards across state jurisdictions, such as noise, visual amenity, shadow flicker and setback distances, providing a consistent approach and expectations for governments, industry and the community. Consistency across the states will not only provide a more equitable outcome for residents potentially affected by wind farms, but may also result in the additional benefit of driving improvements in the technology across the entire market based on the more stringent, while appropriate, standard.
While there may be a number of ways to address these issues, best practice appears to be assigning responsibility for the setting and compliance oversight of environmental-related wind farm standards with the state environmental regulator, while the application of the standards to specific projects rests with the state or local government planning authority. The current arrangements in place in New South Wales and South Australia generally reflect practices along these lines.
Finally, once a wind farm commences operations, it has not achieved formal compliance until all of the post-construction compliance testing has been completed and accepted. Typically, formal post construction testing, such as noise, can only commence once all turbines are operating. The testing itself may take up to 12 months to test and report. Therefore, there may be a period of two or more years where the wind farm is partially or fully operating, but is yet to be confirmed as complaint.
A wind farm may be ‘deemed’ to be compliant in some jurisdictions even though post-construction assessments have not commenced or been completed. There may be an opportunity to introduce more formal processes to properly clarify the deemed compliance period and then confirm when a wind farm is actually compliant once all of the required testing is complete – and the timeframes for which that must occur. This ‘grey area’ of uncertainty of compliance can cause a range of community concerns and also be costly for governing bodies, particularly for larger wind farms that may have a two year plus construction cycle.
Anecdotally, some wind farms have been described as being ‘not non-compliant’ when unable to confirm compliance with required permit conditions, highlighting the difficulty of declaring a wind farm to be ‘non-compliant’ when its default status is compliant. In addition, it may be appropriate to consider that a wind farm is deemed to be operationally compliant during the construction, commissioning and testing periods, but ongoing compliance is subject to final confirmation by the responsible or regulatory authority.
From the Commissioner’s observations, one solution to this issue is for a wind farm to be licensed by the appropriate environmental regulator. Under this scenario, the wind farm would need to confirm and maintain its compliance with the applicable license and permit conditions or risk losing its license to operate in the event of unrectified material breaches of the license and/or permit conditions. The license conditions could include conditions to meet during the period prior to post-construction testing, particularly with regard to handling abnormal or mechanical noise issues.
Measurement approaches for measuring compliance with the standards can also vary between projects and jurisdictions. Given the extraordinary number of variables to be measured, consideration needs to be given to the consistency of measurement, calculations and reporting for assessing environmental measures such as noise and flora and fauna impacts when setting permit or license conditions. For example, there is much scope for variability when selecting the noise data points to be included and also determining the ‘line of best fit’ for those set of noise data points – such variances could mean the difference between compliance or otherwise when assessing the results of a noise testing program.
5.2.1. State governments should review and clarify their current arrangements for the setting of wind farm environmental standards along with the arrangements for oversight and confirmation of compliance with those standards. It is strongly preferred that the department or agency setting and maintaining the various wind farm standards is independent of the department or agency responsible for planning and applying those standards. In addition, the compliance authorities for a wind farm should be clearly defined, transparent, accessible to the community and able to receive and investigate allegations of compliance breaches. Where compliance oversight currently rests with local government, appropriate support and resources should be made available to the council/shire to enable them to effectively perform their compliance and investigative responsibilities, including being equipped with the appropriate policies and procedures to handle alleged breaches of permit/license compliance and/or laws.
5.2.2. Based on the outcome of the review outlined in Recommendation 5.2.1, state governments should consider whether or not the current arrangements are appropriate, effective and consistent with best practices for the independent development, maintenance, compliance management and governance of wind farm environmental standards. If planning functions or local councils are designated as the responsible compliance authority, they should be provided with appropriate support and resources to assist them in carrying out their responsibilities.
5.2.3. In considering the above recommendations and possible reforms, the potential roles of an appropriate independent, state based, compliance agency (such as a state environmental protection or regulatory authority) could include responsibility to:
- Set and maintain the environmental standards applied to wind farms, including noise, shadow flicker, visual amenity, flora and fauna, environment and heritage (noting the role of the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 with regard to Matters of National Environmental Significance including protected flora and fauna), along with specifying the methods and procedures for measurement of the prescribed standards.
- Review planning applications for wind energy projects and recommend/require permit conditions related to the environmental standards. Environmental standard conditions in wind farm permits should clearly state the process for how the measurements are to be undertaken and reported as well as provide the opportunity for peer review of the process, calculations and results.
- Provide or facilitate peer review and audit of expert reports, including review of testing and modelling programs, submitted by the developer related to permit requirements.
- Where appropriate, license the wind farm once it is constructed and issue and monitor license conditions for the operation of the wind farm that may be subject to review and renewal. State Governments should also receive and review regular reporting against those licence conditions from the wind farm operator and may withdraw licences in the event of unrectified material breaches of applicable license and permit conditions.
- Receive and investigate complaints related to environmental standards, including alleged breaches of non-compliance with permit requirements or relevant laws.
- Confirm as required the compliance or non-compliance of a wind farm with regard to environmental standards, related permit conditions and relevant laws.
- Report material wind farm compliance breaches and investigations to the Clean Energy Regulator and other relevant agencies.
- Liaise with other agencies (e.g. Civil Aviation Safety Authority, Australian Government Department of the Environment and Energy) on assessments and compliance matters that involve such agencies.
5.2.4. Planning permits (and/or applicable licenses) for wind farms should clearly state:
- The oversight organisation(s) or person(s) accountable for determining compliance of a wind farm with its permit (and license) conditions, both at post-construction and ongoing operational stages.
- The process and contact details for lodging a complaint or alleged breach of permit (and/or license) compliance.
- The process to be followed in the event that a wind farm is found to be non-compliant with one or more of the permit (and/or license) conditions.
- A requirement for the developer or operator to publish transparently, on the wind farm’s website, the process and contact details to make a complaint or alleged compliance breach to the designated oversight organisation.
5.2.5. During the period between the commencement of a wind farm’s commissioning/operation and the completion of any required post-construction assessments, the wind farm could be designated to be in ‘provisional’ or ‘deemed’ compliance, pending the results of the assessments. In this scenario, a wind farm can only move from ‘provisional compliance’ to being confirmed as ‘compliant’ once the responsible authority (or regulatory authority) has confirmed it is satisfied that the wind farm is compliant as a result of any post-construction assessments. If compliant status is not achieved within a prescribed period, the wind farm may be declared to be non-compliant by the responsible authority or regulator until compliance is reached. Once a wind farm has completed post-construction assessments and confirmed to be in compliance, ongoing compliance is overseen by the designated agency or responsible authority.
5.2.6. If a wind farm’s facilities are deemed by a relevant authority to be in an unrectified material breach of compliance, the wind farm should be required by the responsible compliance authority to cease operating or curtail the non-compliant facilities until compliance can be achieved.
5.2.7. The Federal Government should review the compliance enforcement powers and actions that may be taken by the Clean Energy Regulator in the event of a suspected or reported unrectified material breach of compliance.
5.2.8. Governments should consider reviewing the primary standards across all jurisdictions for noise limits and setback distances. Based on current observations, it would appear that an appropriate level for a consistent noise limit would be 35 dB(A)*, measured outside of the residence (with the result rounded up or down to the nearest whole number), and a minimum setback distance of 1.5 km between a residence and the nearest turbine (note: for turbines with a tip height of 200 metres or greater, a 2 km setback distance may be more appropriate to reduce visual amenity impacts). Applied penalties for specific noise conditions such as tonality and special audible characteristics be set at 5 dB(A), however such noise complaints should also be assessed on a subjective and reasonableness test by an approved, independent expert. Protocols should be developed and in place to clarify interpretation of ‘borrowed’ noise standards. In addition to a setback distance between a turbine and a residence, a minimum setback distance of 200m (as measured at ground level from the centre of the tower or 150m from the extended horizontal blade tip, whichever is the greater) and a neighbour’s boundary fence line or public road carriageway, should also be considered. Finally, consideration should be given to setback distances between a wind farm and a township or city boundary. A distance of 5 km may be appropriate to preserve amenity and provide some flexibility for planning growth of the township (note – consideration of amending these setback provisions may be appropriate in the case of a small-scale, community-supported and owned wind energy facility).
5.2.9. The noise assessment design and compliance testing conditions should include assessment and testing of the wind farm’s electrical infrastructure (transformers, substations, back-up generators etc.) and noise levels from these sources need to be compliant with the applicable standards.
5.2.10.A setback distance between a residence and other infrastructure associated with the wind farm, such as transmission lines, should also be considered to help alleviate visual amenity impacts and noise considerations. This would include a 1 km minimum setback distance between a residence and major transformer or generation infrastructure, such as a terminal substation. Where possible, transmission infrastructure should be placed underground and/or well away from residences and road reserves. If this is not possible, a minimum setback distance of 100m should be considered in planning guidelines for power lines of 66kV or greater. Road safety guidelines and standards must be observed for power poles placed in the road reserve.
5.2.11.Consideration should also be given to the current standards for shadow flicker. A typical standard at present is a limit of 30 hours of shadow flicker per year at a resident’s external window or garden area. This standard, used across Australia, has been sourced from shadow flicker standards developed and used in Europe, where set-back distances to residences are typically less restrictive. At say a 1 km distance from a turbine, it would be very unlikely to receive 30 hours of actual shadow flicker at a residence. A more appropriate standard in the Australian context may be no more than a total 15 hours of actual shadow flicker per year at a residence and no more than 30 minutes of shadow flicker should be experienced on a given day. Neighbours experiencing (or likely to experience) shadow flicker that is annoying should also be provided with the opportunity for having visual screening installed.
5.2.12. Final siting adjustments for turbines during construction (‘micro-siting’) should be limited to a distance of no more than 100m from the approved site location, be no closer to a residence (or property boundary per Recommendation 5.2.7) and be properly documented, including the reasons for the change. Micro-siting of a distance greater than 100m should require written approval from the responsible authority. Power poles installed in the road reserve must comply with relevant standards and guidelines for setback distances from the carriageway, comply with any road safety requirements and road safety barrier specifications, and pole locations must be pre-approved by the responsible authority.