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Responding to Concerns about Wind Energy Prepared by the Canadian Wind Energy Association (CanWEA) August 2007 Concerns around wind The wind industry takes these very seriously:
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Responding to Concernsabout Wind Energy Prepared by the Canadian Wind Energy Association (CanWEA) August 2007
Concerns around wind • The wind industry takes these very seriously: • Public concerns are understandable and they are to be expected with any technology that is new to the social, political and economic landscape • Key is to ensure that good decisions are made on good information … and good science • Important to distinguish between: • Fact (peer-reviewed) and speculation (not reviewed) • Quantitative (science-based) and qualitative (judgement-based) issues
The Issues • Project siting issues: • Audible sound • Low frequency sound (“infrasound”) • Environmental impacts (birds and bats) • Property values • Impacts on agricultural practices • Visual impacts • Setback distances • Interference with telecommunications • Turbine lighting • Shadow flicker • System-wide issues: • Reliability • Economics
Audible sound • What concerns are raised: • “Turbines emit a horrendous noise that makes it impossible to live anywhere near them” • What we know: • Wind turbines do produce sound (“swoosh” of blades) • Actual sound level is influenced by many factors including the type of turbine, wind speed, surrounding topography • Sound often masked by surrounding environment • How we address these concerns: • All projects must meet regulatory requirements for sound • CanWEA Best Practices based on acceptable sound outside dwelling: 40 dBA at 4 m/s rising to 53 dBA at 11 m/s (reflects fact that ambient sound tends to rise with wind speed) • Acceptable separation distances for sound are generally 300 to 600 m (can be less for participating landowners)
Infrasound and Amplitude Modulation (AM) • What concerns are raised: • “Low frequency sound causes health problems” • What we know: • Peer-reviewed studies indicate that levels produced by turbines are similar to ambient levels in the natural environment and are below levels known to have an impact on human health. • Large-scale study in the U.K. concluded that “despite press articles to the contrary, the incidence of wind farm noise and AM is low.” • Study also found that industrial complaints occur 10,000 - 100,000 times more frequently than complaints against wind farms. • U.K. government subsequently stated that “based on these findings, Government does not consider there to be a compelling case for further work into AM” • How we address these concerns: • At this time, there is little scientific basis to support allegations of negative impacts on human health or the environment) • Present peer-reviewed facts on subject
Environmental impacts (avian) • What concerns are raised: • “Wind turbines are a major threat to birds and bats” • What we know: • Wind turbines can potentially have impacts on birds and bats through collisions and habitat disruption • Impact is much less than that of buildings, house cats or the climatic changes that are impacting many bird habitats. • The National Audubon Society stated that “on balance, Audubon strongly supports wind power as a clean alternative energy source that reduces the threat of global warming” • Limited number of cases of high bat mortality at wind farms; the causes are not yet fully understood • How we address these concerns: • The key is proper siting and understanding avian behaviour • Wind farms must get approval from Federal and Provincial environmental assessment processes • Industry working with Bat Conservation International to better understand impacts on bats
Property Values • What concerns are raised: • “Wind turbines will reduce the value of homes in the vicinity” • What we know: • Issue has been studied more in the U.S. than Canada (simply because there is more historical data) • Some studies show property values increasing and others show them declining • Recent study by Renewable Energy Policy Project (REPP) in the U.S. was one of the most comprehensive – it found that there was “no evidence that property values decreased as a result of wind farms […] for the great majority of projects the property values actually rose more quickly in the view shed than they did in the comparable community. Moreover, values increased faster in the view shed after the projects came online than they did before." • How we address these concerns: • CanWEA undertaking a project of similar scope looking at Canadian installations
Impacts on agricultural practices • What concerns are raised: • “Wind turbines interfere with crop dusters and otherwise disrupt how farmers use their land” • What we know: • Turbines only occupy 5% of the land, and cattle often graze up to the base of the turbines • Extra income from turbines helps support agricultural activities (this is why wind is supported by several agriculture federations in the U.S. and Canada) • Some have claimed that turbines amount to “no fly zones” for aerial applicators (crop dusters) – this is patently false according to Transport Canada • Crop dusting currently takes place around at least one wind farm • How we address these concerns: • Encourage wind developers to act proactively with farmers and crop dusters to facilitate crop dusting when and where appropriate • Providing information to farmers and developers
Visual Impacts • What concerns are raised: • “Wind turbines will be a blight on the landscape” • What we know: • “Beauty is in the eye of the beholder” • Early consultation and engagement are key – issue is often tied to concerns around property value • There are many tools available to assist a promoter and community in designing a wind farm to minimize visual impacts, and preserve certain viewscapes • Developer can shift turbine locations to suit community wishes while balancing engineering requirements of site • How we address these concerns: • Difficult to address at a macro-level as the issue is a) project-specific and b) largely qualitative • Encourage early and frequent consultations between developers and communities
Setback Distances • What concerns are raised: • “Setbacks of one to two kilometers are needed between turbines and dwellings to ensure they are not a nuisance” • What we know: • Setbacks between turbines and dwellings should be based on sound levels (generally acceptable: 300 – 600 metres) • Setbacks between turbines and roads / property lines should be based on safety – e.g. ice shedding or turbine failure (generally acceptable: blade length + 10 m) • How we address these concerns: • Currently developing a position on setbacks in Ontario – it is generally considered that this will form the basis for a national standard • Need to work with municipalities and municipal associations to ensure that setbacks are based on Best Practices
Interference with telecommunications • What concerns are raised: • “Wind turbines interfere with radar and television systems” • What we know: • In certain circumstances, wind turbines can negatively affect radio, telecommunications, radar or seismoacoustic systems within a certain distance of the turbines • Must ensure sufficient setbacks from these systems prior to project construction – mitigation measures are possible • Very few documented cases of interference with home TV or telephone reception • How we address these concerns: • CanWEA and the Radio Advisory Board of Canada (RABC) issued guidelines to help determine early in the process if a potential site may interfere with any of these installations • In these cases, mitigation measures canoften rectify any case of interference
Turbine Lighting • What concerns are raised: • “There will be lots of lights on the turbines, blinking incessantly and ruining the view” • What we know: • As with all tall structures, turbines must be lit according to Transport Canada standards • Lighting has to a) provide sufficient warning to pilots, b) not attract birds, and c) not hinder night sky viewing • How we address these concerns: • CanWEA worked with Transport Canada and others (pilot association, Canadian Wildlife Service, skywatchers) to develop standard that addressed wide range of concerns • Current requirements are for single red flashing lights on turbines around the perimeter of the windfarm • System ensures pilot safety and environmental protection, while remaining unobtrusive for communities
Shadow Flicker • What concerns are raised: • “The sun flashing through the rotating blades will act like a strobe light” • What we know: • Effect occurs when a) sun is low enough, b) the turbine shadow falls on a residence, and c) it is not cloudy • Easily modeled as part of the wind farm siting process • No evidence that effect has any impact on humans or animals (note that “flashes” only occur once per second) • No guidelines currently in place in Canada • In Germany, allow 30 hours per year under worst case • How we address these concerns: • Promote awareness of issue and encourage consultations between promoters and adjacent landowners • Issue can easily be addressed at early stage
Reliability • What concerns are raised: • “Wind energy is an intermittent energy source that we cannot count on as part of a reliable electricity system” • What we know: • Although the output of one turbine varies, the output of several wind farms over a wide geographic area is consistent • Accurate wind forecasting can ease wind integration • Wind farms must adhere to grid codes that ensure they contribute to overall grid stability and reliability • Countries like Denmark, Spain and Germany are now able to obtain 22%, 8% and 6% (respectively) of their electricity from wind energy, without jeopardizing system reliability • How we address these concerns: • Work with utilities on grid codes and wind integration studies • Sharing utility experience and knowledge gained from grid integration studies in Canada and the U.S.
Economics • What concerns are raised: • “Wind energy is much more expensive than other generation sources” • “Wind energy receives undue subsidies from government” • What we know: • Current prices range from 8 to 11 cents per kWh for large wind projects (greater than 10 MW) - already cost-effective in comparison with certain conventional generation sources • Wind’s costs are expected to go down while the costs of other technologies (e.g., coal / gas) are expected to go up • Wind can be built quickly and incrementally • All technologies are subsidized, but in different forms (e.g., tax breaks for oil and gas exploration) • How we address these concerns: • Encourage putting a value on wind’s environmental attributes (e.g. generation of offset credits) • Providing info on current wind pricing
Summary • Concerns (and misperceptions) are inevitable • Relatively new technology to the landscape • In absence of facts, misperceptions grow easily • Debate on wind is a good thing • Need to base decisions on solid, peer-reviewed facts • In many cases, the real concern is hidden (e.g. visual impact concerns stem from worries around property value) • Open communications can resolve many issues • Concerns often linked to “getting used to wind” • Familiarity breeds comfort • Industry’s responsibility • CanWEA and members working to establish sound basis for debate, and create effective communications tools
References • Audible sound • “Wind Turbines and Sound: Review and Best Practice Guidelines”, HGC Engineering, February 2007 -http://www.canwea.ca/Environmental_Issues.cfm • CanWEA Fact Sheet: “Visual and sound - The sights and sounds of wind”http://www.canwea.ca/Fact_Sheets_eng.cfm • Infrasound and amplitude modulation • “Research into Aerodynamic Modulation of Wind Turbine Noise”, University of Salford, UK, July 2007 -http://www.berr.gov.uk/files/file40570.pdf • “Wind Turbines and Infrasound”, HGC Engineering, Nov 2006,http://www.canwea.ca/Environmental_Issues.cfm
References • Environmental impacts (avian) • “Wind Turbines and Birds: A Guidance Document for Environmental Assessment - Final Document and Recommended Protocols for Monitoring Impacts of Wind Turbines on Birds”, Canadian Wildlife Service,http://www.cws-scf.ec.gc.ca/publications/eval/index_e.cfm • CanWEA Fact Sheet: Wildlife: Birds, bats and wind energyhttp://www.canwea.ca/Fact_Sheets_eng.cfm • Interference with telecommunications • “Technical Information on the Assessment of the Potential Impact of Wind Turbines on Radio Communication, Radar and Seismoacoustic Systems”, Radio Advisory Board of Canada (RABC) and CanWEA, April 2007http://www.canwea.ca/Standards_and_Technical.cfm
References • Property Values: • "The Effect Of Wind Development On Local Property Values“ Renewable Energy Policy Project, May 2003 -http://www.crest.org/articles/static/1/binaries/wind_online_final.pdf • Reliability: • See materials prepared by the Utility Wind Interest Group (UWIG):http://www.uwig.org/opimpactsdocs.html