A group of 17 teens with mixed hearing ability (most with significant hearing loss) recently took a five-day river trip down the Grand Canyon as part of a program entitled Hear the World Sound Academy: Amplifying the Grand Canyon.  The Sound Academy students traveled with Bill Barkeley, a world-class mountain climber and one of the 15,000 people in the United States with Type 2 Usher’s Syndrome – the leading cause of deaf-blindness in the world. Bill’s 2007 summit of Mount Kilimanjaro shattered expectations and confirmed his role as an advocate and inspiration for the hearing loss community.

A fantastic blog charts the preparations, adventures, and post-trip reflections of the teens and their guides along the way, including staff from the National Park Service Natural Sounds Program.

The German Federal Agency for Nature Conservation (BfN) is working with a consortium of offshore wind companies to find ways to reduce the noise created during construction of wind farms.  An article in Der Spiegel is a good introduction to the efforts:

“From the standpoint of environmental protection, it’s necessary to decrease noise pollution in marine ecosystems,” BfN acknowledges in the introduction of its recent report. The study looks to the guidelines set forth by the Federal Environment Agency (UBA), which suggest that noise outside of a 750 meter radius from the construction site should not exceed 160 decibels. Techniques like bubble curtains, according to the BfN report, can meet this standard.However Greenpeace takes issue with this value because it is based on single-sound exposure — and it takes much more than a single punch into the bed rock of the sea floor to install a wind turbine foundation.

Eight companies are working together to investigate noise-reduction techniques; this article summarizes their goals.  This “Permanent Joint Working Group” is co-hosting a conference in September along with German federal agencies; here’s a brief intro, and here’s the conference website (good luck with your online translation service!)

Here’s a great fifteen-minute radio feature from Voice of America that digs into the issue of shipping noise and its effects on ocean life.  It features Michael Jasny of NRDC, recordings of shipping noise off Vancouver Island, NOAA’s Michael Bahtiarian on their quiet research ships, and Kathy Metcalf of the Chamber of Shipping of America.

Give a listen!

(transcript also included at that page link)

This is somewhat old news, but I just heard about this workshop (thanks to Kathy Hemenway), and it’s full of useful insights: in March, the Consensus Building Institute brought together 100 wind farm developers, environmentalists, state regulators, and technical experts, including proponents and opponents of wind energy, to spend three days discussing what works – and more importantly, what doesn’t work – as communities seek to make informed and effective decisions about wind farm siting.

The quick list of take-aways posted by organizer Larry Suskind on his blog include reminders that there are hundreds of wind farms in the US that can be instructive as we plan new ones, and that it’s unrealistic to expect everyone to get behind ANY project.  Several of his bullet points sound like things that could really help reduce the perceived lack of respect for community concerns that often colors local proceedings, and so reduce the fear and resistance that accompany many wind farm proposals:

• Don’t let wind developers proceed without discussing how turbine operations might have to be restricted to reduce the risk to wildlife and the annoyance to neighbors.
• Do promise to compensate anyone who lives near a proposed facility for any decline in property values that might occur. (It is possible to buy “property value insurance” to make 100% sure that no one suffers any loss of property value.)
• Do realize that everyone reacts differently to noise and visual impacts.

And, in his most far-reaching observation, Suskind stresses the need to “Avoid the dueling experts syndrome that is so common when cases go to court.”  From the outset, he says:

It’s very clear that the traditional “town meeting” or “hearings” approach to energy facility siting is useless. Nobody learns anything at raucous public meetings…..Professionally facilitated stakeholder engagement (involving representatives chosen by the stakeholder groups themselves) can create a level playing field in which informal problem-solving is possible. This all has to be completely open and accountable.

Interesting stuff! And here’s a long blog post from one of the participants, including links to most of the Powerpoints and a lot of audio from the three days.

A drilling rig is up and running in Cook Inlet, along the southern Alaska coast.  The rig, which will remain in the Inlet for 8 or more years, drilling numerous wells during the short summer seasons, expects to complete this first oil and gas well by the end of October, well before ice develops.  Local environmental groups pressed the Army Corps of Engineers and NOAA to not allow the rig into the inlet, citing concerns that oil and gas development activity will negatively impact a recently-designated 3000-square mile critical habitat for the critically endangered local beluga whale population.  In addition to possible impacts of a spill, noise from drilling in a central concern.  The permits allowing drilling require the company to maintain beluga observation crews, and to reduce the speed (and thus noise) of the drill when belugas are nearby, and shut down operations if they come very close.

Cook Inlet is over a hundred miles long, with Anchorage at its inner end; this is also the section of the Inlet that is now designated as critical habitat.  The first drilling operation is in the central part of the critical habitat, between Kenai and Tyonek on the map below.For more on the situation, see the two links above, which go to fairly detailed articles in the local media, and see these two previous AEI posts about the Cook Inlet belugas.

Wind development in the promising borderlands region along the Scottish/English border has come to a standstill, due to very low intensity ground vibrations interfering with a key nuclear test ban monitoring station in Eskdalemur, Scotland.  The Ministry of Defence has been tracking the increasing seismic interference from wind farms in the region, and says that any more would push the wind turbine vibrations  to the point that their seismic monitoring array would no longer be able to reliably hear distant seismic anomalies.

According to an article in The Guardian, “the swishing blades of wind turbines cause vibrations in the ground that can be detected by the sophisticated monitoring equipment at Eskdalemuir. An expert study for the MoD concluded that although the station could cope with some seismic noise, increasing this beyond a certain level would be unacceptable. The limit has now been reached so the ministry is objecting to every new wind turbine within 50km of Eskdalemuir.”

An earlier 80km exclusion zone has been a flexible one, with a period during which the MoD only excluded wind development as close at 10km from the installation, with several wind farms built in the 50km zone (orange circle at right).  At this point, however, the MoD feels they have reached the limit of acceptable infrasonic interference.

One wind power company, REG, which recently had a planned development rejected due to MoD objections, reports that efforts are underway to find a technological fix that could reduce the subtle vibrations that are causing the issues. One idea is to hang weights like pendulums inside turbine towers to deaden the vibrations from the blades. The MoD promised it would reassess its opposition if there were a proven technological solution.

It must be stressed that the vibrations being discussed here are extremely small, far below what would be felt in a home.  We’re talking about a sensitivity that can pick up small seismic anomalies from around the world.  Nonetheless, even though the MoD’s concerns at 10-50km are about impacts far below thresholds that neighbors would notice, I do wonder whether dampening technology developed to address MoD concerns would also reduce some of the more localized vibrations.

We need to keep clear the distinction between pure vibration, transferred through the towers into the ground, and the infrasonic elements of the sound from wind off the blades; it’s unclear that the proposed pedulum-inside solution would affect the in-air infrasonics. For that matter, the press reports are fairly vague about the source of the troubling seismic interference, with that reference above to it being related to wind off the blades, which would, indeed, imply that the strong infrasonic component of wind turbine sound is the source of the problem.  Still, the MoD’s concerns about effects at 10km or 50km should not be taken to mean homes in these ranges are at risk.  However, this does make me wonder whether any other industrial developments (factories, especially) that produce strong infrasonic sound are an issue at distances as far as 50km; if not, it may offer an example of how wind turbines are a relatively unique acoustic presence in the landscape.

This is very interesting, though may get blown out of proportion: in April 2010 a District Environmental Officer submitted a memo to his Ontario Ministry of Environment superiors that offered detailed comments about the field realities he observed, in relation to the proposed Provincial wind farm siting regulations. These regulations currently guide Ontario siting, and call for at least a 550m setback, and sound levels at nearby residences of 40dB or less; the memo cites observations on the ground to recommend limits of under 35dB, and perhaps as low as 30dB.

What’s striking about Cameron Hall’s comments is that his concerns about the 40dB limit are largely similar to those of an increasing number of acousticians who have also been coming to a consensus that lower sound limits may be necessary in many rural locations. In particular, Hall noted that the regulatory 40dB limit should be adjusted downward 5dB due to the pulsing swish of turbine noise, and that it may be necessary to also factor in the acknowledged 3-5dB of error that can occur in sound modeling and the slightly variable sound output of the turbines. Combining these, Hall writes that “it appears reasonable to suggest the setback distances should be calculated using a sound level limit of 30 to 32 dBA at the receptor, instead of the 40dBA sound level limit.”

In addition, Hall stresses another factor often brought up by those trying to understand why 40-45dB turbine noise is stirring up so many complaints: the fact that rural soundscapes in his district are often as quiet at 20-25dB, and noise intrusions should be kept to less than 10dB over that; this leads Hall to similarly suggest Read the rest of this entry »

The island community of Vinalhaven, Maine, remains embroiled in a contentious wind farm noise controversy nearly two years after three turbines began operating there.  The nearby Camden Herald-Gazette recently provided a good, detailed overview of the latest rounds of the back-and-forth between nearby neighbors, the local electrical coop that buys the energy, and state regulators.

An escalating legal tussle has developed since the Fox Island Wind Neighbors paid for noise monitoring and submitted data to the state indicating that the turbines were at times exceeding their regulatory limit.  The most recent salvo is a complaint filed in state court charging that state Department of Environmental Protection commissioners have overstepped their authority by over-ruling staff recommendations on how to deal with the violations.  The neighbors charge that compliance recommendations were watered down, and, most recently, requirements that Fox Island Wind prove ongoing compliance were removed.

The complaint details the unfolding disagreements, beginning in April 2010, continuing through September 2010 when the state DEP officially reported that the turbines were out of compliance by a few decibels in some conditions. Since that time, the complaint charges that three successive DEP Commissioners have meddled in the compliance process, culminating most recently when, according to the petition, “Acting Commissioner Aho, over the objection of DEP professional staff, and in direct contradiction of the findings in the November determination of noncompliance letter, issued a compliance condition order.” The petitioners are asking the court to vacate Aho’s order and replace it with an order drafted by DEP staff, and to review the alleged instances of political intervention.

The article linked above contains extensive quotes from the complaint, as well as from Fox Island Wind, the local developer of the project.

Meanwhile, as part of ongoing efforts to seek innovative solutions short of curtailing operations, the local turbines are in the process of being modified by GE, their manufacturer.  Crews are applying serrations to the trailing edge of the blades; this experimental technique is designed to improve air flow off the blades, thereby reducing noise output by 2-4dB.  See this 2008 AEInews post about earlier research into such techniques.

Throughout the controversy, including in this article, Fox Island Wind has often returned to the idea that the ambient noise of wind in trees is a key factor in the higher recorded sound levels, while neighbors insist that the turbines are clearly heard through this ambient noise. In many ways, the Vinalhaven situation is a perfect example of one of the key, and often-overlooked, factors in wind farm noise debates: the regulatory limit is high enough that even when in compliance, turbines can be clearly the loudest thing in the local soundscape, triggering severe annoyance reactions and sleep disruption for nearby neighbors. While the legal sparring focuses on a 1-3dB violation of the operating standards (a difference in volume that is barely perceptible at best), the underlying fact is that even the allowed 45dB is too loud for many of those living within a half mile or so.

As regular readers will know, the National Park Service completed an epic planning process earlier this year when it released proposed rules governing air tours at Grand Canyon National Park.  After over two decades of discussion, including a failed attempt at coming to a consensus decision with all parties a few years back, NPS planners came up with an approach that was generally well-balanced.  It allows airplanes and helicopters to remain a strong presence in the park, with 8000 more annual flights being allowed than have been occuring in recent years, and half the park still hearing aircraft throughout most of the day.  On the plus side of the ledger for quiet recreation is a groundbreaking no-fly period for an hour after sunrise and an hour before sunset, a window of peace and quiet that will transform the back-country experience for the entire park.  And, flight corridors in two popular back-country areas will alternate seasonally, so there is a time of year in each when it will be noticably more serene.

Nevertheless, the air tour industry claims the plan will put them out of business; it’s not at all clear how this could be, given the greater numbers of flights.  I wonder whether the sunset period is especially popular for flights; if so, this could be a bitter pill for air tour operators to swallow.  Yet it’s hard to deny that this is a time of day when river runners and hikers will find their experience immeasurably improved when birds, wind, and water are the dominant features of the evening soundscape.

Heeding the air tour griping, four Congressmen, two from Arizona and two from Nevada, have added an amendment to a Department of the Interior appropriations bill that would strip all funding for implementation of the rule.  Earlier, the region’s two most powerful Senators, John McCain and Harry Reid, signed a letter opposing the plan, and McCain also attempted (and failed) to push through an amendment blocking it.  For more on the current amendements, see this editorial in the Arizona Republic and this post that details objections from other Arizona representatives and the National Parks Conservation Association.

A couple of articles in this month’s Wind Power Engineering caught my eye.  What follows is more speculative than what you normally find on AEInews, but with that in mind, I encourage you to check the articles out yourself.

Both articles address basic issues regarding wind turbines: the wakes they create downwind, and normal wear and tear of turbine blades.  Neither one considers noise impacts at all, and I don’t have the engineering background that might allow me to make truly informed extrapolations.  But both certainly seem to be worth bearing in mind as project planners and managers address possible noise issues.  The main thing I wonder is whether either of these factors might make turbines slightly louder than expected, or than modeled under more ideal assumptions.

The first article covers a topic we’ve covered here at AEInews before: ongoing research into the turbulent wakes that stretch out downwind from wind turbines:

Today’s massive wind turbines reach into a complicated part of the atmosphere, Julie Lundquist expalins. “If we can understand how gusts and rapid changes in wind direction affect turbine operations and how turbine wakes behave, we can improve design standards, increase efficiency, and reduce the cost of energy.”

The second article focuses on routine maintenance of wind turbine blades, and explains some of the normal wear and tear that needs to be attended to.  It seems likely that at least some blade imperfections would add extra noise, which is of course largely caused by the airflow coming off the blades.

Traditionally, less attention has been paid to the repair and upkeep of turbine blades versus other components. Instead, preventive maintenance programs have focused on the internal mechanics of turbines due to the predictability of their maintenance requirements. Typical preventive maintenance plans for internal components fall into 3, 6, and 12-month work schedules. By nature, blade repairs are more difficult to plan. Blade damage can arise in manufacturing, transportation, and tower construction and erection. However, maintenance issues more often occur in the field from leading-edge erosion, weather, and other factors. A lack of predictability and historical data complicates preventive maintenance for blades.

Commercial turbines can have tip speeds of over 200 miles per hour. At these speeds, rain drops can take on the impact of small stones, and blowing sand has the erosion power of a plasma cutter. Studies have shown blade roughness and accumulated debris on the blades can reduce wind turbine performance by 5 to 30%. Blades that aren’t working efficiently can also create vibration that contributes to gearbox failures.

Joshua Crayton, a contractor who provides blade maintenance services, notes that regular inspections are especially important in windy seasons and following lightning storms. “Operators and owners are inheriting their wind farm assets and the responsibility of maintaining blades that are no longer covered by the (manufacturer) warranty,” he says. “Like any business, wind farm owners and operators typically run a lean staff and may not have an experienced maintenance technician in-house. Partnering with a service company can help them design a long-term, post warranty, preventive maintenance plan.”According to Crayton, a maintenance plan should be initiated before the warranty period expires. “A thorough internal and external blade inspection should be scheduled in the warranty period,” he says. “Once owners and operators take over care of a wind farm, these inspections should take place every two years. Personnel can conduct simple ground inspections while on-site, but there is no substitution for a close, visual examination performed uptower.”

PLUS: Two other short articles may also be of interest: one on design concepts for a 20MW turbine (today’s big ones are 2MW), and the other a very positive development, a 36MW battery designed to stablize output to the grid from wind farms.

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.

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 »

Five environmental organizations have filed a legal petition asking NOAA to enforce speed limits in National Marine Sanctuaries off the California coast. If NOAA does not take action within a year, the groups say they may sue to under the Marine Mammal Protection Act. “Our marine sanctuaries should be a safe harbor for marine life, but instead whales in California are at constant risk of being run over by big ships,” said Miyoko Sakashita, oceans director at the Center for Biological Diversity. “Mandatory speed limits for ships traveling through our marine sanctuaries will save whales and clean our air.” Slower ship speeds also significantly reduce a ship’s noise, which could be a welcome relief in such a heavily trafficked area.

In the past decade, nearly 50 large whales off California have been struck by ships. Last year, at least six were killed in collisions. A key factor in the decision about lowering ship speeds is likely to be whether the loss of less than ten whales a year warrants the change (more whales may be struck and sink without being seen).  Along portions of the East Coast, federal authorities have imposed a 10-knot speed limit for ships 65 feet or longer for the past several years in order to protect the North Atlantic right whale, which is critically endangered, numbering only around 300 animals, so the loss of any individual is a blow to the population’s future.

The groups are advocating a similar mandatory speed limit of 10 knots (about 11 mph) for all ships larger than 65 feet while sailing through California’s four national marine sanctuaries, which stretch from the Marin Headlands north of San Francisco, 300 miles down the coast to the Channel Islands north of Los Angeles.  Ship speeds are now usually 13-25 knots. Since 2007, when four blue whales were struck by ships near the Channel Islands National Marine Sanctuary, NOAA has issued seasonal bulletins urging a 10 knot speed limit from May-December, when the blues are most numerous; environmental groups say most ships ignore this voluntary advisory, while shipping groups say most ships do adhere to it.

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).

At most of the places where the National Park Service and FAA have commenced air tour management planning (ATMP), there is already a deeply entrenched local air tour economy, as well as a visitor expectation that they can take flight in order to see the beauty from above.  The Grand Canyon is of course the Mother of All Overflight Controversies; similarly, the the Black Hills/Mt. Rushmore and Hawaii Volcanoes ATMPs also dove into situations where thousands of annual flights were already taking place.

But now for something completely different: At Mt. Rainier National Park near Seattle, only 114 flights are currently allowed each year, with actual numbers apparently lower.  This provides a rare opportunity to give real consideration to Alternatives that truly maintain natural quiet on the mountain.  The Park is currently accepting comments on a set of draft alternatives for use in the ongoing EIS process.  Two of the proposed alternatives would greatly reduce noise in the park backcountry: Alternative 1 simply bans all flights over the park, and Alternative 4 keeps planes to the far periphery of the park, and at high altitudes.  Alternative 3 allows 55 flights per year to circle the peak, and introduces the NPS’s recent innovation (being spearheaded at the Grand Canyon) of setting aside no-fly times – in this case, weekends, and sunrise/sunset on Monday-Thursday, and keeps planes at 2000 feet or more.  Alternative 2 maintains current use patterns around the peak, capping flights at 114 per year.

Truthfully, any of these options will maintain Mt. Rainier as a place where hikers can experience the natural soundscape with minimal intrusion.  But, the opportunity to establish a precedent for keeping commercial air tours out of relatively pristine National Park lands is one that is worth keeping on the table; we encourage support for the inclusion of the “no air tours” alternative.  Comments are being accepted through May 16.

NPS Mt. Rainier ATMP page ; Mt. Rainier Draft Alternatives

And remember, comments are being accepted through early June on Draft Alternatives at Hawaii Volcanoes National Park, too.  There, Alternatives range from 28,000 flights per year to “no air tours” (though this will allow flights around the periphery, and over 5000 feet within the park).  You can read about the process and comment here, and you can download the alternatives here.

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.

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.”