The UK wind industry is scrambling to respond to a High Court ruling that affirmed the legaltiy of conditions placed on the Den Brook wind farm near Devon, limiting ampltude modulation of wind turbine noise to a level that could be very hard to comply with.  After years of pooh-poohing the reports of neighbors who said that the pulsing quality of the turbine noise made it especially hard to live with, including a much-criticized study a few years back that found nearly no AM at UK wind farms, Renewable UK (formerly the British Wind Energy Association) is fast-tracking a far-reaching study of AM, which they hope to complete in just seven months.

The new study, funded by Renewable UK (a trade organization of wind industry companies), aims to develop better models for predicting AM, including assessment of the effects of high turbulance and closely spaced turbines, as well as noise predictions both nearby and at a distance.  In addition, they aim to develop a listening test that could inform a possible penalty-assessment approach to dealing with AM noise when it does occur; such an approach, common in many regulations, forces the overall noise level to be lower when AM is present.

After years of claimng there is no need to assess or regulate AM, it appears that the industry has now found itself sufferering the consequences of denying the problem.  Instead of working to create regulations that take the issue seriously (whether or not it is common), the industry is now vulnerable to being out of compliance when AM does occur.

The recent ruling unfolded along just these lines.  The wind developer claimed noise would be inaudible or at least not problematic, while local resident Mike Hulme was unconvinced and wanted to be sure that if AM did occur, there would be consequences for the wind farm.  His acoustical consultant Mike Stigwood told the Noise Bulletin: “I devised an excess amplitude modulation condition based on my findings and measurements at other wind farms that was worded simply and made an exceedence a breach. It was a simple stand-alone condition.” In an earlier round of litigation on these conditions, the developers proposd a penalty approach to dealing with non-compliance (thus seemingly implying that AM could occur), but the Inspector who wrote the rules did not incorporate their proposal, because he felt the proposal lacked necessary detail to apply effectively.

While the High Court ruling denied the appeal’s goal of stopping the Den Brook wind farm from proceeding, it affirmed the validity of the AM condition and stressed that the wind farm must comply with the rules as written, which are very stingent: whenever sound levels are over 28dB, turbine noise (measured in very short time intervals) can’t vary by more than 3dB.  To avoid penalizing random momentary fluctuations, the AM provision applies only when this pulsing of sound occurs more than five times in two minutes, and for at least six minutes in any hour.

While ruling that the condition as written was valid, the Court said that there was no provision in the ordinance that would allow any sort of penalty or other way of dealing with non-compliance with the AM limit, short of shutting down or changing operations so as to remove the pulsing sound. It’s likely that this High Court ruling will provide precedent and justification for the development of ordinances that do address Amplitude Modulation as a particular quality of wind turbine sound, and that future ordinances will be developed with a penalty scheme to minimize the negative effects of this pulsing quality of wind turbines, by requiring them to be quieter when AM is present; in practice, this is likely to mean that wind farms will need to be built a bit farther from homes, so that their noise is quieter all the time, leaving room for AM factor to be added without breaking the noise limits.

For more, see this article in The Environmentalist, a leading UK magazine, or read the High Court ruling here. Also fo note, the June 2011 edition of Noise Bulletin includes an in-depth article on the court case, along with a good summary of the Wind Turbine Noise 2011 conference, including a sidebar introducing the industry-funded AM research program; Noise Bulletin is not viewable online, but free sample issues and trial subscriptions are available on their website.

An Ontario Environmental Review Tribunal has ruled that the Kent Breeze Wind Farm can be built, denying an appeal by the a local resident and a community group that challenged the wind farm’s permits, largely on the basis of health effects that it may cause among nearby residents. Since Kent Breeze is the first wind farm to be approved under Ontario’s new green energy development rules, this was seen as a key to near-term wind development in the province.

The Tribunal’s 223-page ruling provides a fascinating, in-depth look at the state of current wind farm science and policy; many pages are devoted to the testimony of each of the witnesses, which included well-known researchers with a wide range of viewpoints, including Rick James, Geoff Levanthall, Christopher Hanning, Robert Colby, and many others.  I highly recommend that anyone interested in these issues download the full report and give it a look.

An article in the Windsor Star includes predictable responses from all concerned. “We are pleased with the decision of the tribunal,” said Jennifer Lomas, spokesperson for Suncor, the developer. “In terms of the alleged health concerns, we are committed to understanding the interaction of our operations and the environment. We meet all operating standards for these projects, this includes strict compliance to regulatory (rules).” Meanwhile, John Laforet, head of Wind Concerns Ontario, stressed that “(The tribunal) said there were risks and uncertainties. We aren’t debating whether there is a problem or not, but whether there is responsible development. We want believable studies and setbacks based on the outcomes of those studies…We are hopeful this ruling, while it’s a battle lost, it’s a step toward winning the war provincewide.”

Indeed, the Tribunal stressed in its ruling that “It is hoped that the legitimate debates surrounding the effects of turbines will spawn further independent research to the point that some of the challenges posed in this Hearing will be reduced over time.”   Futher, “The Tribunal accepts that indirect (health) effects are a complex matter and that there is no reason to ignore serious effects that have a psychological component.” This is a stark contrast to the CanWEA/AWEA health effects study, which focused nearly solely on direct health impacts, dismissed indirect effects triggered by annoyance, stress, or sleep disruption as insignificant or subjective, and concluded that there was scant reason to look deeper at the issue.

Click on through below the fold for AEI’s in-depth summation of the key points made in the full ruling.

Read the rest of this entry »

The first field results from a Caltech research team led by John Dabiri have been published, and they suggest that Dabiri’s new approach to wind generation may be just what rural communities have been hoping for: the ability to proceed with widespread wind energy development without changing the character of local landscapes and soundscapes.

Dabiri’s team is looking at wind energy efficiency from an entirely new perspective: rather than designing individual turbines to capture as much of the wind energy passing through their blades as possible, they’re looking to capture as much of the wind energy in the projects footprint as possible.  Instead of the 300-400 foot 3-armed turbines we’re used to, the Caltech team is optimizing a tightly-packed array of 30-foot spinning vertical tubes (vertical-axis turbines) that look more like egg beaters or old-fashioned lawnmowers turned on end.  Inspired by fish schooling, the turbines use the air flow from one another to optimize energy capture and efficiency; by contrast, giant horizontal-axis turbines (the standard design we’re familiar with) need to be very far apart so that their turbulent wakes don’t interfere with each other.

In the first field season, last summer, a tiny test plot of just six turbines was arrayed in various configurations, so the  team could find what works best.  This summer, 24 turbines are being used in the second year of field tests.  Last summer’s results, while clearly preliminary, are exciting: the array produced 21-47 watts of electricity per square meter.  That may not sound like much, but a bit of high school math reveals that if this design scales up (even assuming just 30 watts/meter), a 1km by 1km plot of land (a bit over a half mile on each side) would produce as much electricity as one of today’s wind farms with two hundred 1.5MW 300-foot towers spread over many square miles. Put another way, a patch of land 200 feet on each side would produce the same amount of electricity as a single 1.5MW turbine, which generally needs a safety buffer of at least 500 feet on all sides.  The downsides of the new approach are that the productive wind installation would use all of the land in its footprint, unlike current wind farms in which the distantly-spaced turbines leave plenty of room for grazing or planting.  Horizontal axis turbines can also suffer more stress under high winds, though undoubtedly new materials and engineering approaches will address this issue.

There’s clearly a long way to go to bring this new design to utility-scale wind production, but of all the new approaches to wind energy, this is one of the most promising!

For more on Dabiri’s work, see this Caltech press release and visit Dabiri’s lab’s web page, which includes a video and links to a Powerpoint and the recently published paper.

The Syracuse Post-Standard reports that a study of real estate sales in three upstate New York counties has found that being closer to wind turbines can lead to reduced sales prices.  In two of the three counties, property values appear to have dropped by 8-15% for homes situated a half mile from the nearest turbine (which usually means several more are within a mile or two); the price drop was only slightly less for homes within a mile, while there was a smaller, 2-8% drop for homes within 3 miles of a turbine.  However, the third county studied showed no price reduction after the wind farm was constructed; the authors found that in this county, prices actually rose a bit just after construction, then settled  back to no significant change. This study uses a hedonic analysis methodology similar to two previous studies (Hoen and Hinman) that found no significant price change.  This new study, by Martin Heintzelman and Carrie Tuttle of Clarkson University, differs from the previous studies in that it does not combine all results, but rather looks at each county individually.

The Heintzelman study is still being finalized; an earlier version that combined all locations into an overall negative impact has circulated since March, but a new version that separates the locations and finds the more nuanced results is now available.

Riga, Michigan has adopted a wind farm ordinance that limits noise at nearby residences to 45dB during the day and 40dB at night, and the wind developer says they cannot meet these limits on the land they’ve leased.  The rules also establish a distance limit of 4x the height of the turbines; this amounts to a bit over a third of a mile. There’s a good chance that wind boosters will spur a township referendum to repeal the new rules.  Three other local townships where wind development is planned are working on ordinances, and there is some indication that they will come to a similar conclusion about acceptable noise levels.  It is not clear from initial press reports whether the Riga ordinance includes the option of obtaining permission from willing landowners to build closer or allow slightly more noise at their homes.

Joshua Nolan, director of the nonprofit Interstate Informed Citizens Coalition, said “The ordinance as it exists is probably the best compromise.” With many acousticians suggesting a 35dB night time noise limit (see recent AEI Wind Farm Noise 2011 report), and the industry more accustomed to building wind farms to meet a 45-50db threshold, the Riga ordinance is a moderate attempt to provide more noise protection for neighbors.  Yet it may also be a good illustration of the fact that such protection can indeed preclude development in some rural areas with more population density than the wide-open west.  Many towns and counties are attempting to find the middle ground where development can take place, but citizens are not unduly impacted by noise; in some areas, there may not be enough room to keep turbines far enough from homes to meet this goal.  In this situations, the localities will need to decide whether wind development or local peace and quiet is more important to them.  In some areas, it may be possible to find enough willing neighbors to accept louder noise at their homes to allow smaller wind projects to proceed, while keeping turbines noise to 40dB, or even 35db, at homes of those who wish to maintain the current rural soundscape.

An unprecedented court case has begun in the UK, which could determine whether noise impacts become more widely considered to be of importance around wind farms.  Jane and Julian Davis moved out of their home in 2006 after the wind farm began operation, saying the sound was ‘unbearable’ even though they wore earplugs at night and installed double glazing at the farmhouse in Deeping St Nicholas, Lincolnshire. in 2008 they were unable to get a real estate agent to list the home for sale, saying they could not determine a fair market value due to the noise from the turbines just under a kiilometer (about a half mile) away.

Their case is being heard by London’s High Court, and is believed to be the first UK case to seek damages for a “noise nuisance” caused by a wind farm.  According to a detailed post at Business Green,

Mrs Davis, whose husband’s family cultivated Grays Farm for more than 20 years before they moved out, said it had been a “nightmare” living there, and the family had no option but to leave. She told the Strand News Service on Monday that the humming sound created by the turbines was very unpredictable and mainly occurred at night. “You can never get to bed with the assurance that you will stay asleep,” she said. Their lawyers are seeking either a permanent injunction to shut down the turbines or damages of up to £2.5m to compensate the couple for the disruptive effect on their lives.

The case, which is expected to last three weeks, started on Monday but was adjourned until today so the judge and lawyers in the case could carry out a site visit. “Their lives have been wholly disrupted by that noise,” he told the court, also alleging the main operator had tried to “impose a code of silence on those examining or recording the noise that the turbines in this location have caused”.

But William Norris, QC for the owners, operators and landlords of the wind farm, rejected claims that the machines created an unacceptable noise nuisance, suggesting the couple may have become “unduly sensitised to sounds that would not adversely affect the ordinary person”. He accepted that their “amenity” had been affected, but said the couple had “a gross over-reaction to what they undoubtedly do hear”.

The Spaulding Guardian elaborated on the two sides’ perspectives:

The Davis’s barrister said in court that the developers tried to “attack the credibility and reasonableness of the claimants rather than examine what they were actually being told. From the defendants’ witness statements, and the material they wish to put before the court, it seems that those attempts to undermine the claimants, to say they are over-sensitive, that they are exaggerating and over-reacting, will continue during the trial,” the barrister added.

He claimed the defendants had been irked by Mrs Davis’ eagerness to “speak publicly” and that she was being attacked for refusing to “put up with the noise”.

The QC for the developers and turbine host families accepted the couple heard sounds they genuinely believed to be “objectionable” after the turbines were installed but argued they could not be considered “dispassionate and reliable witnesses” and said Mrs Davis is prone to exaggeration and “favours hyperbole rather than balanced description”.

The case adjourned on July 6 for the judge and and lawyers to do a site visit.

The Minnesota PUC has approved a controversial wind farm in Goodhue County, where a county ordinance setting a nearly half-mile setback was facing off against a 1500-foot setback that was originally planned for the project.  The PUC slightly increased the setback limit from 1500 feet to 6 rotor diameters, or 1630 feet.  But while giving approval for the closer siting, the PUC also is requiring developers to engage in “good faith” efforts to negotiate agreements with neighbors closer than the county limit, which is 10 rotor diameters, or just under a half mile.  It’s unclear how such negotiations might proceed, or whether the PUC or courts would respond if negotiations fail.   Over 200 landowners have signed lease agreements to host turbines, while a contingent of locals has pushed for greater protections for neighbors.

UPDATE, 9/14/11: Goodhue County will file request for PUC to reconsider their permit.
UPDATE, 12/4/11: Goodhue County decides not to appeal the PUC decision.
UPDATE 2, 9/15/11: Sixteen motions were filed with the PUC to reconsider the permit, with some of the filers using fightin’ words; a court challenge is also mentioned as a possibility.

The PUC’s decision is a stumbling lurch toward the sort of approach that makes sense to AEI, which would establish larger setbacks such as the county standard, while encouraging negotiated agreements with neighbors who live closer.

For more on the Minnesota decision, see these three articles from RenewableEnergie.com and this one from North American Windpower. This Reuters piece last week set the stage nicely as well.

UPDATE, August 1: 200 residents who live within a half mile of the proposed project and are not already in line to receive lease payments as hosts of turbines have been offered $10,750 each by the developers of the 50-turbine wind farm.  This is in response to the PUC order that they make a good faith effort to obtain agreements from these neighbors.  The offers total about $2 million, a small increase in the previous $180 million project budget.  It’s interesting to me that there are that many landowners within a half mile; another 200 have are already part of the project as lessees. Past experience suggests that in areas like this, with so many people being affected, there is apt to be a higher likelihood of negative reactions, as compared to wind farms in locations where residences are sparse, and mostly working farms or ranches.

An Australian wind farm was derailed this week when the Environment Resources and Development Court in the state of South Australia ruled in favor of a dairy farmer who challenged an earlier approval.  The Court rejected evidence related to possible health effects, but ruled that the planned wind farm would impact on the “visual amenity” of the area to an unacceptable degree.  The proposed turbine layout included several turbines within one kilometer (just over a half mile) of Richard Partridge’s dairy farm; 14 other homes were also within 1km of the nearest turbine, with several, including Partridge, facing the prospect of having turbines within 2km (a mile and a quarter) in several directions.  In his submissions of concern, Partridge stressed that audible noise would impact his quality of life and possibly the well-being of thousands of nearby dairy cows; his statement to a Senate Committee concluded:

Our landscape is a non-renewable resource. We cannot create more of it. It is the background and setting to our lives, and helps to identify us as Australians. The Australian landscape is a resource which we hold in trust for future generations. As its present custodians we have a responsibility to conserve and manage it wisely, protecting it from inappropriate development, so that it will enrich the lives of our children and successive generations.

While the Court heard evidence from a Waubra woman whose home 700m (2100 feet) from turbines was purchased by the developer after she complained of health impacts, the justices ruled that health effects are too uncertain to be blamed on the turbines, but that the rural nature of the area deserved more protection than the Allendale East Wind Farm layout could provide.  The deciding factor appeared to be the dramatic new vertical elements being introduced into the landscape by the turbines (see judgement). In Australia and New Zealand, “rural amenity” is more widely considered a valid basis for assessing the impacts of development, while in the US and Canada, assessment tends to stress objective measurements of noise, with quality of life concerns minimized as simply NIMBYism.

As for noise levels, the Court noted that it accepted at face value testimony from wind farm neighbors elsewhere who reported clearly hearing turbines at distances from 700m to 3.2km, but could not extrapolate from these reports elsewhere to apply such concerns to this site.  Justices agreed with testimony from the developer’s acoustical experts, which project noise levels to remain below the statutory limit of 40dB or 5dB over ambient, whichever is greater.

After long months of gestation, examination, and procrastination, this year’s Wind Farm Noise report is ready to share!  So, here it is.

It’s also viewable here on SlideShare. And, you can download the 55-page report, and much of the source material, on the new AEI Wind Farm Noise Resources page. Lemme know what you think of it!

AEI_WindFarmNoise2011

The past week has seen a flurry of new reports and articles that aim to debunk the idea that wind farm noise should be taken seriously as a concern when siting new wind farms.  AEI’s upcoming Wind Farm Noise 2011 report will address the issue in great depth when it’s released in about a week, but for now I wanted to make a few comments about the recent releases.

Two reports came from Canadian environmental groups that advocate expansion of wind energy and are frustrated by local resistance, especially in Ontario.  I share their support for wind energy providing an increasing percentage of our electrical generating capacity, and have little problem with the bulk of these reports; but in each case, I feel that their treatment of noise issues misdirects attention away from the very real problem at the core of the debate: when wind turbines are built closer than a kilometer or so from homes in rural areas, a high proportion of those nearby neighbors experience significant quality of life impacts due to audible turbine noise.

Sierra Club Canada released a 40-page report Read the rest of this entry »

This column was published recently in the Record-Patriot (Frankfort, Michigan).  It offers a pretty solid short version of AEI’s current perspective on wind farm noise issues.

Windfarm noise: Moderate, but often disruptive
Guest Viewpoint by Jim Cummings, Executive Director, Acoustic Ecology Institute

Some local residents asked me to take a look at the recent Guest Viewpoint from Duke Energy about the planned Gail Windpower Project, and to share my experience in studying community responses to similar wind farms in other parts of the country. The Acoustic Ecology Institute produces analyses and layman summaries on various noise-related issues; after assessing a wide spectrum of reports, scientific studies, and personal accounts, our goal is to present a picture that helps makes sense of the confusingly differing viewpoints held by those who are strong advocates for one side or the other. This column will draw on an in-depth presentation on community responses to wind farm noise that I put together at the request of the New England branch of the Wind Powering America program, a wind advocacy project of the US Department of Energy. The full presentation can be found at https://www.aeinews.org/archives/972

Wind farm noise issues are subtler than the anti-wind groups may fear, but much more real than the industry would like to believe. Note that I don’t say “than the industry would like you to believe.” In general, I don’t see the industry as fostering mis-information, so much as being overly satisfied with information that is becoming outdated, especially as we get more experience with community reaction in the upper midwest and northeast. See this column from Renewable Energy World for more on the shift that is taking place: https://www.aeinews.org/archives/1236

The bottom line, based on what we’ve seen in other communities, as well as what I’ve heard myself when visiting wind farms (including the truly impressive Sweetwater wind farm region mentioned in the Duke column), is that wind turbines are often clearly audible to a half mile or so, and somewhat audible beyond that, out to a mile or so at times, depending on wind and topography. At distances beyond a few hundred feet, the noise is never what we’d call objectively “loud,” but it is, with some regularity, notably louder than other existing ambient noises, especially in rural landscapes where there are no roads with steady traffic within earshot. It’s long been recognized that when a new noise source approaches 10dB louder than existing ambient, it will trigger widespread negative responses. That’s at the core of today’s increasingly vehement debate about wind farm noise impacts. As many wind farm neighbors have noted with surprise, 45dB can seem startlingly loud in quiet rural areas! Read the rest of this entry »

A new research program at the University of Adelaide aims to learn more about the complex physical dynamics that create the primary noise in large wind turbines: the air turbulence off the trailing edges of the huge blades, which turn at speeds of up to a hundred miles per hour at their tips.

As explained in an article in AdelaideNow:

“If we can understand this fundamental science, we can then look at ways of controlling the noise, through changing the shape of the rotor blades or using active control devices at the blade edges to disrupt the pattern of turbulence,” said research leader Dr Con Doolan.

“Wind turbine noise is very directional. Someone living at the base might not have a problem but two kilometres away, it might be keeping them awake at night,” Dr Doolan said. “Likewise this broadband `hissing’ noise modulates up and down as the blades rotate and we think that’s what makes it so annoying.

“Wind turbine noise is controversial but there’s no doubt that there is noise and that it seems to be more annoying than other types of noise at the same level. Finding ways of controlling and reducing this noise will help us make the most of this very effective means of generating large amounts of electricity with next to zero carbon emissions.”

Further coverage is available from UPI.

A recent article in the New York Times focuses on the financial benefits coming into communities in eastern Oregon, where wind energy development is booming despite state noise limits of 36dB at homes. Most wind farms in the US and Canada face noise limits in the 45-50dB range, with some regs going as low as 40dB at night; wind industry representatives generally claim that lower noise limits will preclude wind development. Oregon’s approach to wind farm siting, which imposes a cautionary noise limit to protect residents from unwanted noise, while allowing for easy exemptions when residents are willing to live closer to turbines, appears to AEI to be a constructive response that addresses concerns about protecting the rural soundscape while also encouraging wind development.

Ione, Oregon wind farm; Leah Nash for the New York Times

In Sherman County, landowners earn $5500 per year per turbine, often hosting ten or more per landowner, often in wheat fields.  The County earns enough in taxes and fees to keep schools flush with cash, and issue a modest annual check to all heads of household.

While a 36dB noise limit aims to keep audible turbine noise close enough to existing quietest background ambient levels to be relatively unobtrusive, it should be noted that some residents report noise levels well above 36dB at times, suggesting that the noise modeling used in laying out the wind farms may have been faulty.  Apparently, even with the lower noise limits, some homes are within a half mile of turbines, a range in which turbines are often easily audible and can sometimes cause sleep disruption.  The state law allows companies to obtain waivers from residents in order to build closer and create to noise levels over 36dB, and some wind companies are seeking such waivers from nearby neighbors, in exchange for one-time or recurring payments.  These waivers could also protect companies from situations in which actual noise levels rise slightly above the levels predicted by pre-construction noise models, as recently occurred at the Willow Creek Wind Farm in the same region.

Thanks to Google News’ nifty customized news sections, I hear about articles worldwide that contain terms interesting to AEI, such as “ocean noise,” “wind turbine noise,” and, yup, “Acoustic Ecology.”  Yesterday I saw that David Colby, one of the authors of the widely-read report on wind turbine health effects, had responded to an article that questioned his integrity on that project.  It sounded like his self-defense was justified, but for some reasons in his defense he noted that while AEI had critiqued the report, our comments should be disregarded because we are “wind objectors.”

Well, having invested considerable time and effort in establishing a reputation as an honest broker of the science and policy debates surrounding various noise-related environmental issues (with DOE’s NEWEEP, NOAA, US Navy, Canadian DFO, and others affirming that by inviting my participation in public and private workshops and working groups), I was rather offended by his characterization.  I quickly submitted a letter to the editor noting that AEI believes wind energy is an important part of our energy future, and that our focus on noise issues has from the start been focused on the idea that if impacts on nearby neighbors are not taken seriously, the future growth of the industry will be jeopardized.  In several road trips over the past year, I’ve come across large wind farms in Texas, Iowa, Nebraska, and Wyoming, all of which were truly impressive and made a lot of sense on the landscape where they were.  Nearly without exception, they were also miles from any homes.  It’s only as we move wind farms into rural areas that are not primarily working landscapes that we’re finding a significant proportion of folks within a half mile or mile saying that their quality of life is being affected by the noise (which is, in my experience, nearly always clearly audible at a half mile, and barely audible at greater distances).

Here’s my brief letter in defense of AEI’s balance, and here’s AEI’s initial critique that Colby refers to, which seems to me to be quite measured, and in fact supportive of much of what they found.

Regular readers will know that I’m excited by the potentials for far-offshore floating wind turbines.  Less construction noise, less disturbance of the seafloor, more construction can take place on land rather than at sea (meaning less loud boat activity)…..it all adds up to much less noise impact in our coastal ocean environment, which is very sensitive to new noise.  Not only that, but the winds are stronger farther out.

Renewable Energy World has a great current overview of where the R&D is at today for floating turbines, with summaries of each of the leading designs being tested, and assessment of the likely timeframe (the cautious among them still say we’re a decade away; some are more bullish).  Some of the commenters throw in the bonus idea that these installations could add wave energy generators as one way to address the higher costs the floating technologies.

IMAGE: Developed by Norwegian energy company Statoil ASA, Hywind is the world’s first full-scale floating wind turbine.  Located around ten kilometers off the southwest coast of Norway, the structure itself is a steel cylinder, similar to a spar buoy, filled with a ballast of water and rocks, which extends 100 meters beneath the sea’s surface.  Attached to the seabed by a three-point mooring spread, it can be employed at ocean depths of 120 to 700 meters.
Photo: Trude Refsahl / Statoil

A couple on Wolfe Island, Ontario are asking their local officials to reduce the valuation of their home by about 17% due to its proximity to a wind farm that began operating two years ago.  Wolfe Island is in the St. Lawrence, and sits a couple miles from the New York town of Cape Vincent, where another wind farm is planned.

Ed and Gail Kenney had their home assessed at $357,000 just as the wind farm construction was beginning; a more recent appraisal in early 2010 came in at $283-295,000; the appraiser said she took the proximity of the wind farm into account. The Kenney’s home sits just over 1 kilomerter, or six-tenths of a mile, from the nearest turbine.  Their claim asserts that the lights and the noise from the turbines are the factors that reduce the value.

A witness for the Municipal Property Assessment Corporation, which disputes the reduced valuation, and maintains that the 2008 assessed value is still valid, cited property sales in Dufferin County where 133 turbines are now operating.  Seventeen homes have sold, though the distances were not stated; four sold for more than the initial asking price, and the others showed no clear relationship to proximity to turbines, so “there’s not enough evidence to warrant a negative adjustment.”

UPDATE, 4/16/12: The Assessment Review Board ruled that proximity to wind farms should not be a factor in county assessments of properties. The Kenneys claim that virtually no homes have been sold near the turbines on Wolfe Island since the wind farm became operational.

UPDATE, 7/3/13: The latest update from Wolfe Island suggests that 78 properties have seen substantial reductions in assessed value between 2008 and 2012; most are within 2000 feet of turbines, though turbine proximity is not cited as the reason for the reductions. See more here

As noted in AEI’s previous coverage of property values research, while there is little evidence of decreased property values due to seeing turbines in the distance, there is less clarity about whether values decrease within a half mile or mile, where noise issues become a factor.  As in the Dufferin County sales, there are  generally too few sales at close range to produce statistically significant trends one way or the other. In 2008, several property owners near a Prince Edward Island wind farm had their property values reduced by the town by about 10%.  Developers of two different wind farms in Ontario – one of the Dufferin County farms and one in Ripley – have purchased several homes from neighbors after they found noise of the turbines disruptive. UPDATE, 10/1/11: This story from the CBC discusses several homeowners in Ontario who have been unable to attract buyers or who sold for a loss after a wind farm began operating nearby (including four of the homes bought by developers).

Suncor and Acciona Energy recently purchased four homes near the 38-turbine Ripley Wind Power Project, buying out several neighbors who had been pushing the companies to deal with noise issues at their homes.

According to The Kincardine News:

The Ripley-area residents had approached municipal council in 2009 about a rash of health problems, “including high blood pressure, headaches, sleep disturbances, the sensation of bugs crawling on the skin, humming in the head, non-stop ringing in the ears and heart palpitations,” they believed were caused by their proximity to the project.

“We take the concerns of all our stakeholders seriously,” said Acciona’s Paul Austin, adding they’ve been working with local stakeholders to answer questions and understand their concerns since the project began. “After a prolonged period of consultation that involved a number of third-party studies and tests, it was agreed upon that the only solution that could meet the needs of this small group of local landowners was to purchase their homes.”  Austin also stressed that the buyout was not linked to health issues, or, more precisely, he said that  “no link between the operation of our Ripley Wind Power Project and the health concerns of our neighbours could be discovered, and so no damages were awarded or necessary.” (ie, no damages were paid; yet the houses were purchased)

Interestingly, the sales prices were significant, yet appear to be something that the developers feel they can take on as part of the cost of doing business in this area: the homes were purchased at agreed-upon market rates of $230K, $250K, $165K, and $400K. (see this post for link to real estate sales records obtained by a local anti-wind group)

Maine’s Office of Energy Independence and Security has delivered a long-awaited report on wind farm siting to the state legislature.  The lead recommendation is that the minimum distance between commercial wind turbines and residences be nearly doubled, to 1000 feet; current standards are based on safety, not noise, while the proposed increase is meant to address noise impacts.  It appears that the 1000 foot distance is based on keeping noise levels below 55dB during the day and 45dB at night, which is what is required for all noise sources in rural Maine.

The proposal was met with resistance from both sides.  Jeremy Payne of the Maine Renewable Energy Association said the new setback is arbitrary, and that “we’re comfortable that the existing setbacks are protective of public safety and health.” Karen Bessey Pease of Friends of the Highland Mountains, which has been proposing one-mile setbacks, said that 1000 feet is “just too little to protect citizens.”  David Wylie of Vinalhaven (image above) was more blunt: “One thousand feet is really ludicrous. We’re 2,400 feet away and it’s really unbearable. It shakes the house and goes through our bones and bodies.”

Here at AEI, we noted that the experts consulted for the report did not include any acousticians who have suggested that lower noise limits may be necessary for wind farms than for other noise sources.  We were pleased and somewhat surprised to see AEI cited numerous times, though in some cases our points were taken partially out of context and some points which were accurately presented were apparently ignored in coming to the conclusions. In particular, we were pleased to see that the report included our assessment of peer-reviewed Scandinavian studies that suggest that when wind turbine noise tops 40dB, annoyance spikes in rural areas to 25-45% of those hearing these levels – though of course the 1000 foot setback guarantees that many of the closest neighbors will indeed be disturbed (it’s likely that those from 1000 to at least 3500 feet will regularly hear noise levels of over 40dB).  Two citations of our work implied that very few wind farms cause noise issues, but left out the fact that this is because most are far from homes and that a much larger proportion of wind farms within a half mile or mile of homes do cause problems, especially in rural areas that are not working farm and ranch landscapes.  Likewise, a citation suggesting that “Typically, between 5-20% of people, with higher levels of around 20% of people in rural areas, are highly annoyed by wind turbine noise” neglected to note these figures are for all those who can hear turbines at any volume or distance; again, the key point is obscured: that those within a half mile or so are apparently negatively impacted at a high rate, and those within a mile or so also likely to be more bothered. Even overlooking the subtle misinterpretation, I am left to wonder: is this report suggesting that causing a high level of annoyance in 20% of the rural population an acceptable outcome?  As noted by many acousticians, community noise standards are typically set to minimize negative impacts more effectively than that.

Read more at the Portland Press Herald, or: Download the full report.

The US National Renewable Energy Laboratory is about to begin a new study of the turbulent wakes that appear downwind from wind turbines.  Such turbulence can decrease the efficiency of turbines as well as creating physical stresses on the machinery; many researchers also suspect that inconsistent wind speeds across the rotor diameter contributes to increased noise.  It’s certainly easy to imagine that turbines inside the wakes pictured at the left (from an offshore wind farm in Denmark, where moisture reveals the normally invisible patterns) might be under stresses that would increase noise output.

For more on the NREL study, see this feature in Science Daily.

A new study finds that there is plenty of already disturbed land in the US to meet the 20% by 2030 goal for wind energy production.  Noting that habitat fragmentation is a key issue that can slow wind development, the researchers took a state-by-state approach that looked at both disturbed landscapes and wind resources, to see whether there is enough disturbed land (farmland, oil and gas fields, roads) on which to build out our wind future.

The answer: clearly yes. In fact, there’s enough disturbed land to build more than ten times the number of turbines needed.  While some states, including Maine, California, Pennsylvania, and Michigan, don’t have enough undisturbed land to meet their goals, many others have far more potential capacity than needed (see chart). “A disturbance-focused development strategy would avert the conversion of ~2.3 million hectares of undisturbed lands relative to the unconstrained scenario in which development is based solely on maximizing wind potential….Agriculture and oil and gas make up the vast majority of the disturbed lands identified in our analysis, such that removal of other disturbed lands would not qualitatively change our results. However, we believe that ridges surrounding abandoned surface mines and areas adjacent to existing roads also constitute disturbed areas where wind energy development should be considered.”

The researchers also note that “Placing turbines on disturbed lands may also benefit the expansion of transmission lines and associated infrastructure that will be critical to facilitate wind development. Because disturbed lands are already in areas of high road and transmission line density, they may ease the development of new or expanded transmission capacity. “

While their analysis focused on ground-based conservation needs, and so it is likely that some areas of bird and bat migration would need to be excluded from their disturbed-land analysis, there is enough extra potential capacity to easily move in this direction. What’s needed, they authors suggest, is policies that make it cheaper to build in disturbed land and more expensive to build on pristine land, which “could improve public value for both wind energy and biodiversity conservation.”

Read full paper online here.

It’s “wind week” at the Maine state legislature, where the Utilities and Energy Committee is hearing two days of testimony on a slate of 14 bills that have been introduced to regulate wind energy development.  One bill would mandate property value guarantees, and another would impose setbacks of a mile and a quarter from homes.  Maine’s been a hot spot for community noise issues, with a ridgeline wind farm in Mars Hill spurring noise and health complaints from most of the residents within a half mile or so, and a three-turbine farm in Vinalhaven triggering noise issues for around half of the similarly nearby neighbors.

Legislators heard starkly differing views from supporters of the wind industry and community groups that have been pushing for more protection for landowners who don’t want to hear turbines from their homes.  Predictably enough, the rhetoric was at times extreme, with one opponent positing that development up til now has been “a well-planned legislative fraud perpetrated on the citizens of Maine.”  On the other side of the coin, a local realtor said, “I have seen no negative impacts whatsoever on real estate values in Mars Hill,” but didn’t specify whether any of the homes within a half mile or so that have been severely impacted have been on the market.  (Ed. note: while most evidence agrees that prices of homes a mile or more from wind farms are not dramatically affected, there is less clarity or consensus about the few homes within a half mile or mile; in rare cases, homes in this range have been abandoned by owners.  It’s clear that easy reassurances about impacts in the community at large, ie within several miles or within sight of turbines, often don’t reflect the experiences of those living closest.)

The Portland Press Herald and  Bangor Daily News have more coverage of the hearings, including this exchange:

Several people living near wind power facilities questioned whether a few hundred temporary construction jobs is a worthwhile trade-off when the turbines force some homeowners who support the local economy year-round to move away.

“I’m listening to employee after employee come up and say, ‘I’m more important than somebody’s home,’” said Carrie Bennett, who lives near a three-turbine facility near Freedom. “Do you want to buy my house? Do you want to live in my house? Of course not.”

New wind farm permitting rules adopted in the Australian state of Victoria place permitting authority in the hands of local councils, rather than the state Minister for Planning.  During  the recent campaign, the newly elected state government had called for  2km setbacks from non-consenting landowners, and shared payment plans for all residents within 1km.  While these provisions are not included in the new rules, local authorities are granted authority to assess “high amenity noise impacts,” which could lead to noise limits lower than those currently required by the law (of course, lower noise limits lead to larger setbacks from homes).

In Australia, a fair amount of research has looked at local reactions to wind farm noise, and the concept of “rural amenity” has emerged as a likely  factor in areas where moderate noise triggers more widespread complaints than expected.  The idea is basically that residents in some areas value rural quiet extremely highly, and in these places even distant turbines can trigger complaints; several windfarms have faced widespread reaction from  residents 2km (about 1.25 miles) away.

An Ontario Superior Court has dismissed a legal challenge to the province’s wind farm siting standards, which call for 550 meter (1800 foot) setbacks in most cases. The Court ruled that it could only judge whether the process of coming up with the regulations followed proper protocols, including public consultation and the use of science-based evidence in coming to its conclusions. That lifts a cloud of uncertainty from developers of wind farms, says the president of the Canadian Wind Energy Association. “We’re expecting this to be a record year for wind development in Ontario,” Robert Hornung said in an interview. “This decision just helps everybody put their head down and focus on the work.”

“It is not the court’s function to question the wisdom of the minister’s decision, or even whether it was reasonable,” the court ruled Thursday. “If the minister followed the process mandates by the Environmental Bill of Rights, his decision is unassailable on a judicial review application.”

The Court pointed out that the province’s Environmental Review Tribunal (ERT) can consider whether setbacks are reasonable, on a case-by-case basis.  In fact, an ERT review is currently underway, challenging the standard setbacks at a wind farm in Chatham-Kent, the first new wind farm to be permitted under the new law. Read the rest of this entry »

Following up on our previous coverage now-infamous Wisconsin Governor Scott Walker’s call for larger wind turbine setbacks, the a joint legislative committee that reviews pending new rules voted to abandon the planned implementation of new wind farm siting rules scheduled to go into effect on March 1. (See PSC site detailing the work of the committee that proposed the new rules, and this opinion piece by the committee vice-chair and co-author of a minority report supporting larger setbacks)

Republican legislators, now in the majority, agreed with Governor Walker that the rules as crafted would allow turbines too close to neighboring properties; Walker and his allies frame their objections as a property rights issue. Committee co-chair Rep. Jim Ott, said. “The biggest issue we heard came from testifiers at the hearing that 1,250 ft. is too close and will result in shadow flicker and noise issues.” Some wind farm neighbors also cite health issues resulting from stress and loss of sleep caused by the turbine noise, which also influenced the legislators.

The American Wind Energy Association said the PSC rule was restrictive enough, given that it set specific noise limits and restrictions on shadow flicker in addition to turbine distance setbacks.

“These rules were developed collaboratively by the wind energy industry and all major stakeholders in Wisconsin, based on input from six public hearings and two years of information gathering, to protect the interests of all involved parties,” said Jeff Anthony, director of business development at the American Wind Energy Association and a Wisconsin resident.

“We heard nearly nine hours of testimony during February’s hearing,” Ott said. “Based on the testimony — some pro and a lot of con — we decided to hold a motion to suspend the rule. This is a situation where the legislature is exercising its oversight of a public agency.”  It is expected that the legislature will authorize a new round of rule-making, with one bill calling on the PSC to revisit the issue and submit a new proposal within 7 months.

An article from Vermont offers an unusually detailed and complete report on a Public Service Board hearing about noise at a proposed wind farm in Lowell.  I highly recommend it.

The article summarizes the testimony of two noise experts, each of whom was proposing what they felt was a proper conservative noise limit; the article presents each approach quite well, and gives a good sense of the judgment calls that regulators are being asked to make about wind farm noise.

Les Blomberg urged a 35dB standard at property lines, which would help keep noise levels low enough for folks to put a chair in the yard and relax.  He used an EPA technique to suggest that turbine noise should be regulated to a lower sound level than other noise sources.

Ken Kalinsky proposed a 45dB standard outside the home, which would protect against sleep disruption, and not limit outdoor conversation, though may interfere with quieter outdoor activities such as listening to songbirds.  He said that 45dB is more conservative a limit than those used in many other places, notably the World Health Organization standard for protecting health.

Now go read the whole article!