There are many questions people have asked us about wind and solar farms and many sources of information on the internet.
Following are some common questions and links to various third party sites that may be of further assistance.
There haven’t been broad scale studies into the impact of wind farms on surrounding property values in Australia to date. Some smaller studies have been undertaken. The findings of these do vary depending on the location, density and use of a particular area. Following are a range of articles looking at this topic:
Using the wind is one of the cleanest and most sustainable ways to generate electricity as it does not produce toxic pollution or global warming emissions. Wind is also abundant, inexhaustible, and affordable, which makes it a viable and large-scale alternative to fossil fuels. When compared to the environmental impacts of fossil fuels as a source of power, the impacts of a wind farm is relatively minor.
Many land uses such as agriculture are compatible with wind and solar farms. While a wind farm may cover a large area of land only small areas of turbine foundations and infrastructure are made unavailable for use. The ground disturbance and vegetation clearing required for wind farms is minimal. If wind farms are decommissioned, the landscape can be returned to its prior condition.
Wind farm developers undertake environmental assessments for each wind farm proposal to ensure that the potential impacts on the local environment (eg plants, animals, soils) are avoided or minimised.
Turbine locations and operations are often modified, as part of the approval process, to avoid or minimise impacts on threatened species or communities and their habitats. Any unavoidable impacts can be offset with conservation improvements of similar ecosystems which are unaffected by the proposal.
In addition, wind developers are often able to integrate beneficial local environmental measures into their construction and operational activities. This can include planting native species, protecting native bush areas, pest and weed management or erosion control.
Compared to other human activities, wind farms have an extremely low impact on birds. Wind turbines do occasionally kill birds, but so do people, vehicles, houses, buildings, powerlines and communication towers – and in much greater numbers.
The National Wind Coordinating Committee’s 2001 literature review of bird deaths resulting from collisions with vehicles and other man-made infrastructure in the US estimated annual bird deaths associated with various causes:
- vehicles: 60-80 million (different studies in different areas found between 2.7 and 96.3 bird deaths per mile of road each year)
- buildings and windows: 98-980 million
- powerlines: up to 174 million
- communications towers: 4-50 million
- wind farms: 10-40,000 (an average of 2.19 bird deaths per wind turbine per year in the US).
While extensive data is not yet available for wind farms in Australia, early results from bird monitoring at Codrington Wind Farm show an estimated bird mortality rate of 1.2 birds per turbine each year.
Other significant causes of bird deaths include house cats, pesticides, oil spills, electrocution and disease. A 2007 study by the Government of South Australia shows one domestic cat kills more birds in a year than one wind turbine.”
“When it comes to potential impacts on threatened bird species, wind farms have to go through a rigorous planning process to ensure any such risks are fully assessed before a project can go ahead.
It`s important to note, the presence of a threatened bird species in the vicinity of a proposed wind farm doesn’t necessarily mean the wind farm will pose a direct threat. Assessing the risk to birds is complicated, and depends on:
- whether the bird species typically flies at rotor swept height – many birds rarely reach rotor swept height, which is approximately 60 m if the bird species would normally fly through the wind farm area
- how the wind turbines are spaced, and where they are in relation to habitat areas, such as waterways, breeding sites, foraging areas and flocking sites avoidance rates for the species
- the layout and design of the wind farm, and what avoidance, mitigation and management measures are in place.”
National Wind Coordinating Committee’s Avian Collisions with Wind Turbines: A Summary of Existing Studies and Comparisons to Other Sources of Avian Collision Mortality in the United States (2001)
Government of South Australia’s Cats and Wildlife – how you can protect both (2007)”
Wind turbines are audible but you can hold a normal conversation under a wind turbine operating at maximum speed, without raising your voice.
Wind farms in Australia are designed to meet strict noise regulations, introduced by state environmental protection agencies to protect the amenity of nearby residents. The regulations require that noise for proposed wind farms is modelled and meets specified ‘acceptable’ limits. This means that people living near wind farms might hear them at times, but what is heard will be within the regulated limits.
Sound is defined by its frequency (the pitch of the sound), measured in hertz (Hz) and pressure level (the ‘loudness of the sound’) which is measured in decibels (dB). People can generally hear frequencies between 20 Hz and 20,000 Hz and wind farms tend to generate sounds in this range.
Wind farms make three main sounds:
- the “swoosh” generated by the blade tip travelling through the air
- low frequency sound from gears and other mechanical movement
- small pressure pulses when the blades interact with wind flow around the tower.
Decibels are a logarithmic scale which means that a doubling of the perceived noise is equivalent to an increase of 10 dBA. This table shows a few different noise sources with associated noise levels. The levels here are indicative only. How you hear a noise is subjective and depends on background noises and other conditions.
|Noise source||Noise level (dBA)|
|Jet aircraft at 250m||140|
|Pneumatic drill at 7m||95|
|Truck at 50km/h at 100m||65|
|Conversation or busy general office||60|
|Car at 65km/h at 100m||55|
|Busy road at 5km||34 – 45|
|Wind turbine at 350m||35 – 45|
|Rural night-time background||20 – 40|
Reference: Dr Mark Diesendorf’s book Greenhouse Solutions with Sustainable Energy (2007), chapter 6.
Information can also be found at the Department of Health & Human Services, State Government of Victoria see: here
The National Health and Medical Research Council convened the NHMRC Wind Farms and Human Health Reference Group from 1 February 2012 to 31 January 2015 to oversee a comprehensive review of the evidence on the possible health effects of wind farms. The NHMRC Statement and Information Paper: Evidence on Wind Farms and Human Health can be found at: https://www.nhmrc.gov.au/guidelines-publications/eh57 or downloaded here.
An extract from page 1 of the document follows: “Statement on the evidence”
- Examining whether wind farm emissions may affect human health is complex, as both the character of the emissions and individual perceptions of them are highly variable.
- After careful consideration and deliberation, NHMRC concluded that there is currently no consistent evidence that wind farms cause adverse health effects in humans. This finding reflects the results and limitations of the direct evidence and also takes into account parallel evidence on the health effects of similar emissions from other sources.
- Given the poor quality of current evidence and the concern expressed by some members of the community, there is a need for high quality research into possible health effects of wind farms, particularly within 1,500 metres (m)”