This is information from an institute dedicated to understanding sound in response to Massachusetts foolish report claiming that Industrial Wind Turbines have NO health impact.
Items from The Acoustic Ecology Institute thanks to Mr Jim Cummings
Jan 15 2012
Health, Human impacts, News, Wind turbines No Comments »
The Oregon Health Authority has released a draft of its first “Strategic Health Impact Assessment on Wind Energy Development in Oregon.” The approach taken by Oregon health officials marks a subtle but significant departure from previous government reports on the topic. Most fundamentally, rather than being simply a literature review of past studies, this paper is a first attempt to sketch out the parameters by which health impacts of specific projects might later be assessed. The hope is that a final HIA would provide a basic understanding and framework that could allow future specific developments to look at local details, rather than repeating this big-picture overview. While it’s not all that clear how this framework for understanding the possible direct and indirect health effects will be used to actually assess on-the-ground responses in communities, the paper is notable for inclusion of several indirect pathways by which annoyance and sleep disruption can lead to physiological impacts, and also for its consideration of the impact of community discord on stress and well-being.
To begin with, the authors emphasize that “HIAs are guided by the World Health Organization’s definition of health as ‘a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.’” At the same time, the report makes clear that completely avoiding all health effects is not necessarily the goal, recognizing that economic development and public health are not in opposition to each other, but mutually inter-related, so that “the long-term public interest is best served when the interdependence of these goals is recognized and balanced through a process that empowers people to shape their lives and communities.” This investigation has particular timeliness in many Oregon communities, given that Oregon’s current 2500MW of wind capacity will double when projects under construction or approved are completed, and would more than triple if those in the permitting process now are built out.
The report follows many others in finding that direct impact on the body from the sound levels commonly received around wind farms is not likely, and that infrasound is generally below levels that are likely to be perceived. But unlike other reports, which often simply mention that annoyance is possible in response to audible wind farm sound, this one looks more closely at the health effects of stress and annoyance. In particular, it concludes: ”Sound from wind energy facilities in Oregon could potentially impact people’s health and well-being if it increases sound levels by more than 10dBA, or results in long-term outdoor community sound levels above 35-40dBA.” And further: “The potential impacts from wind turbine sound could range from moderate disturbance to serious annoyance, sleep disturbance and decreased quality of life. Chronic stress and sleep disturbance could increase risks for cardiovascular disease, decreased immune function, endocrine disorders, mental illness, and other effects. Many of the possible long-term health effects may result from or be exacerbated by sleep disturbance from night-time wind turbine sound.”
Especially notable in this report is an entire section on “community conflict,” and the conclusion that “Community conflict over controversial siting or environmental decisions may contribute to or exacerbate this stress, and thus increase the risks of these negative health effects,” and that “rural communities may be disproportionately impacted by community-level conflicts because these conflicts may erode traditional sources of social and interactional support that community members rely on.”
Also strikingly, the report acknowledges that sound levels “at or near” regulatory limits can trigger these effects. Therefore, it recommends that “planners should evaluate and implement strategies to minimize sound generation from wind turbines when outdoor sound levels are at or near Oregon’s standard for wind turbine noise,” and suggest close consideration of site-specific factors that can affect sound propagation and perceived loudness, especially at night. The idea appears to be that this site-specific analysis can help to minimize the error factors in more generalized sound modeling (which can routinely lead to brief periods of sound well above that suggested by the models), thus reducing the likelihood of excess or “just at the limit” sound events.
These and other considerations of subtle, indirect effects, as well as differences in noise sensitivity and responses to wind farms among both individuals and communities, make this report far more comprehensive than most that have come before. It does not, however, make a case that all these impacts or health effects are necessarily likely to occur at levels that would preclude wind development. I recommend you read it in full to get a better sense of the overall context within which these innovative perspectives are included.
In particular, the report stresses that long-term average sound remains the best predictor of annoyance and thus possible health effects; it notes an EPA recommendation that if a sound source is new to an area, 5dB should be added to its sound output in assessing likely negative community responses, though again notes that problems are related to 5-10dBA increases in 24-hour sound averages caused by turbines, more so than short-term increases in sound.
And, while noting that “a small number of epidemiological studies have linked wind turbine noise to increased annoyance, feelings of stress and irritation, sleep disturbance, and decreased quality of life,” with “annoyance from wind turbine noise…more likely when levels exceed 35-40dBA,” the report also stresses that except for some sleep disruption and reports of lower energy, people closer to turbines may report a lower sense of how healthy they perceive their environment to be, or lower satisfaction with living conditions, but that there is generally “no difference between the two groups for social, psychological, and general health-related quality of life.” Still the report acknowledges the role (and limitations) of case series reports, which are more often simply dismissed by other similar reports. Finally, the report stresses the contributing role played by general attitudes toward the wind energy development, and encourages an open process that provides opportunities for widespread public engagement and a clear process for reporting noise or health issues if they arise, as well as urging developers to outline and communicate proposed mitigation techniques that can be employed should problems arise.
Oregon’s draft HIA can be downloaded here as a pdf; comments are being accepted through March 30 at this website.
Jan 12 2012
Human impacts, News, Wind turbines 2 Comments »
This probably looked like a great place for a wind farm: only a handful of homes within a half mile, and nearly all the more densely-populated roads to the east and west well over a mile from the ridge on Flathead Mountain, where the Record Hill Windfarm was to be built. After the bad experiences at Mars Hill and Vinalhaven, where residents within 3000-3500 feet reported serious noise issues, this location likely seemed like just the ticket. But this week, after a month of operations, several residents told the Roxbury selectmen that the slowly turning turbines had changed their peaceful lakeside existence for the worse.
Linda Kuras told the selectmen, “I know what the ice in the lake sounds like and this noise is not that. This is a repetitive thumping sound: a whemp, whemp. What was once a quiet night’s sleep is now this.” She described the low-frequency sound as being akin to heavy items in a clothes dryer tumbling around. Selectman Tim DeRouche concurred, saying, “It sounds like wind gushing right over the mountain. It sounds like a jet.” Both DeRouche and Kuras live along Roxbury Pond (noted as Ellis Pond on Google Maps); the closest homes along the lake shore are between a mile and a quarter and a mile and a half from the turbines, according to this map from Record Hill Wind.
Selectmen encouraged residents to report their complaints to the State Department of Environmental Protection, which is still in the process of setting up a complaint management system for this new wind farm. Record Hill’s director of community relations, a Roxbury resident, was in attendance, and noted the issues; he also shared that one turbine is awaiting a replacement part to fix a problem (the article didn’t clarify whether this turbine is operating or not).
By all accounts, the noise at the pond is not particularly loud, and is only sometimes audible, most notably when the pond and environs are otherwise dead quiet (which, we may presume, is one of the reasons many folks live there).
Jan 02 2012
Human impacts, Wind turbines No Comments »
A new book, Windfall: Wind Energy in America Today, by historian Robert Righter, was recently published by University of Oklahoma Press. Righter also wrote an earlier history of wind energy, published by UofO Press in 1996. In the intervening years, of course, the wind industry has blossomed from its initial mini-boom-and-bust in the California hills (Altamont, anyone?), with bigger turbines, larger government incentives, and growing commitment to reducing our reliance on fossil fuels (coal and natural gas) for electric generation all leading Righter to feel that an update was in order.
As a hearty advocate of wind energy and continued rapid growth of the industry, Righter will startle many with his strong call for not building turbines “where they are not wanted.” He spends chunks of three chapters addressing the increasing problems caused by wind farm noise in rural communities, chides developers for not building farther from unwilling neighbors, and says that new development should be focused on the remote high plains, rather than more densely populated rural landscapes in the upper midwest and northeast. While not ruling out wind farms in the latter areas, he calls for far more sensitivity to the quality of life concerns of residents. (Ed. note: Righter’s book shares a title with, but should be clearly distinguished from, a recent documentary investigating local anti-wind backlash in a NY town.)
Righter seems to be especially sensitive to the fact that today’s turbines are huge mechanical intrusions on pastoral landscapes, a far cry from the windmills of earlier generations. At the same time, he suggests that a look back at earlier technological innovations (including transmission lines, oil pump jacks, and agricultural watering systems) suggests that most of us tend to become accustomed to new intrusions after a while, noting that outside of wilderness areas, “it is difficult to view a landscape devoid of a human imprint.”
He acknowledges the fact that impacts on a few can’t always outweigh the benefits for the many in generating electricity without burning carbon or generating nuclear waste, but goes on to ask:
No matter how admirable this is, should a few people pay the price for benefits to the many? Should rural regions lose the amenities and psychological comforts of living there to serve the city? Should metropolitan areas enjoy abundant electricity while rural people forfeit the very qualities that took them to the countryside in the first place? The macro-scale benefits of wind energy seldom impress local opponents, who have micro-scale concerns. The turbines’ benefits are hardly palpable to impacted residents, whereas the visual impact is a constant reminder of the loss of a cherished landscape.
Righter also takes a realistic stance about the fact that our appetite for electricity leads to inevitable conflicts wherever we might want to generate it. He says, “…wind turbines are ugly – but the public produced the problem and must now live with it. Turbine retribution is the price we must pay for a lavish electrical lifestyle.”
But unlike most wind boosters, he doesn’t content himself with this simple formulation. He goes on to stress that even as recently as 2000, most experts felt that technical hurdles would keep turbines from getting much bigger than they were then (500kW-1MW). The leaps that have taken place, with 3MW and larger turbines in new wind farms, startle even him: ”They do not impact a landscape as much as dominate it….Their size makes it practically impossible to suggest that wind turbines can blend technology with nature.” He joins one of his fellow participants in a cross-disciplinary symposium on NIMBY issues, stressing: ”Wind energy developers must realize the ‘important links among landscape, memory, and beauty in achieving a better quality of life.’ This concept is not always appreciated by wind developers, resulting in bitter feeling, often ultimately reaching the courts.”
He was obviously touched by the experience of Dale Rankin and several neighbors in Texas, who were affected by the 421-turbine Horse Hollow Wind Farm. Righter generally agrees with my experience there, that such wide open spaces seem the perfect place for generating lots of energy from the wind. But two of these hundreds of turbines changed Rankin’s life. These two sat between his house and some wooded hills, and Righter says that to him, “the turbines seemed inappropriate for this bucolic scene. For the Rankins the change is a sad story of landscape loss…” He asked whether the developer had talked with them before siting the turbines here, but they hadn’t, since the land belonged to a neighbor and local setback requirements were met, so “the utility company placed the turbines where its grid pattern determined they should be. Perhaps such a policy represents efficiency and good engineering, but (reflects) arrogance and poor public relations….(The developer) crushed Rankin with their lawyers when fairness and reason could have ameliorated the situation…the company could well have compromised on the siting of two turbines. But they did not.”
On the question of noise, Righter is equally sensitive and adamant, stressing the need to set noise standards based on quiet night time conditions, “for a wind turbine should not be allowed to invade a home and rob residents of their peace of mind.” He says, “When I first started studying the NIMBY response to turbines I was convinced that viewshed issues were at the heart of people’s response. Now i realize that the noise effects are more significant, particularly because residents to not anticipate such strong reactions until the turbines are up and running – by which time, of course, it is almost impossible to perform meaningful mitigation.”
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Dec 31 2011
Science, Wind turbines 2 Comments »
If AEI were a mass media outlet, publishing this on New Year’s Eve would be considered an attempt to “bury” the story on a weekend when few people are following the news. But since our readership works on a longer time scale and are likely to find their way here over the next couple of weeks, I hope you’ll instead consider this a New Year present! It’s taken many (many…) hours of work, and I hope it helps all those working on wind farm noise issues – including local and state regulators, environmental consultants, wind developers, and community groups – to make sense of the insanely confusing world of low-frequency noise and infrasound. Here’s to a constructive 2012 as we continue to work toward siting policies that protect residents from unwanted changes to their sense of place while encouraging responsible and widespread growth of wind energy.
Download this extended post as a 22-page pdf file
As regular readers will know, AEI’s wind farm coverage has focused primarily on the ways that nearby neighbors respond to the audible noise from wind turbines, with far less emphasis on infrasound. However, given the ongoing public dialogue about the contribution of infrasound and low-frequency sound to the annoyance, sleep disruption, or health effects reported by some wind farm neighbors, I do like to keep abreast of research into the lower end of the sound spectrum. In this post, I’ll be summarizing several papers that have appeared in journals and conference proceedings over the past several months. This will be a much longer post than normal, but I encourage you to take the time to read through it, and to download the source papers for further study. What you’ll find here is a close reading of work from both mainstream and more cautionary acousticians, which I believe will help you to understand the subtleties of our current state of understanding in a new and clearer way.
I think it’s fair to say that the bottom line continues to be roughly the same as it’s been: wind turbines clearly produce much of their sound energy at lower frequencies, including the low end of the audible spectrum (20-250Hz) and the infrasonic range (below 20Hz, which is generally below the range humans tend to hear, simply because it has to be very loud to be perceptible). Conventional wisdom continues to be that the infrasound in wind turbine noise is well below human perceptual limits, even of the more sensitive fringe of the population. This summary doesn’t directly challenge that idea, though as you’ll see, there are some indications that we may have been a bit too quick to entirely rule out any perception of infrasound produced by wind turbines. Still, I hasten to stress that any possible connection between physically perceptible infrasound and health effects remains beyond the scope of most of these papers (with a couple of exceptions).
More importantly, though, it’s increasingly being recognized that low-frequency audible sound could very well be a key factor in widespread annoyance about wind farm noise. It’s important to not conflate infrasound and low-frequency sound; while the former is (always or mostly) imperceptible, the latter is clearly very audible in many situations, and indeed, is the dominant sound component of wind farm noise at moderate and larger distances. It’s quite likely that much of the annoyance people report could be triggered by very low frequency, moderately audible noise, which can be more ear-catching (or perhaps even cause physiological reactions) when it contains one or more dominant tones or fluctuates rapidly. Further, increasing evidence confirms neighbors’ reports that moderate but extremely bothersome low frequency noise can be more perceptible inside their homes than outside. These elements are part of the reason that several of the papers here from relatively mainstream perspectives (and which consider infrasound a non- or minimal issue) recommend lower noise limits than the 45-50dB standard commonly used in the US; you’ll see in these papers that 40dBA is becoming a common recommendation. Most of the more cautionary acousticians tend to recommend 30-35dB; it’s striking to me that the gap between these two perspectives has narrowed considerably in the last year or so.
Among the highlights of the recent research is Møller and Pedersen’s finding that larger turbines produce more low-frequency sound (especially audible low-frequency), and that in many atmospheric conditions, sound levels will remain annoyingly high for much farther than often assumed by more idealized sound modeling. Also of note, Bray and James’ field measurements of wind turbine sound, using equipment designed to capture very short time segments, reveals a remarkable variability and surprisingly high peak sound levels in the low-frequency and infrasonic sound, to a degree that raises questions about our tendency to rely on longer-time-period averages that indicate infrasound is always well below perceptual limits. As we look more closely into low-frequency and infrasound data, both the mainstream papers and the more cautionary acousticians’ work suggest that these questions are far from settled.
(I should clarify that my use of the word “mainstream” is meant to simply mean studies by folks working with techniques and perspectives on bothersome noise levels that have been standard in noise control assessment for many community noise sources. And conversely, the use of the term “cautionary acousticians” does not imply they are less qualified or biased in any way. Indeed, most of them have decades of noise control experience and have been drawn to the study of wind farm noise only because of the unexpectedly robust complaints that have arisen, and are professionally interested in trying to ascertain the reasons, either by using innovative measurement techniques or closely assessing annoyance patterns. They may be more “cautionary” in their recommended noise limits simply because they’ve looked more closely at specific problems, rather than keeping their distance and approaching the issue through standard noise modeling and analysis techniques.)
Some of the papers I’m summarizing here address aspects of annoyance and sound characteristics of wind farm noise that are not limited to low frequency and infrasound issues (especially including acknowledgement of the extreme variability of the overall sound levels); these papers provide important perspectives that may help us to understand why wind farms are producing more annoyance reactions than we might expect, considering their moderate sound levels.
For more (much more…but worth it!), click on through to read lay summaries of the following recent papers:
- Møller and CS Pedersen. Low-frequency noise from large wind turbines. J. Acoust. Soc. Am. 129 (6), June 2011, 3727-3744.
- O’Neal, Hellweg, Lempeter. Low frequency noise and infrasound from wind turbines. Noise Control Eng. J. 59 (2), March-April 2011.
- Bolin et al. Infrasound and low frequency noise from wind turbines: exposure and health effects. Environ. Res. Lett. 6 (2011) 035103
- Bray and James. Dynamic measurements of wind turbine acoustic signals, employing sound quality engineering methods considering the time and frequency sensitivities of human perception. Noise-Con 2011.
- Stephen E. Ambrose and Robert W. Rand. The Bruce McPherson Infrasound and Low Frequency Noise Study: Adverse health effects produced by large industrial wind turbines confirmed. December 14, 2011.
- David Hessler, Best Practices Guidelines for Assessing Sound Emissions From Proposed Wind Farms and Measuring the Performance of Completed Projects. Prepared for the Minnesota Public Utilities Commission, under the auspices of the National Association of Regulatory Utility Commissioners (NARUC). October 13, 2011.
- Knopper and Ollsen. Health effects and wind turbines: A review of the literature. Environmental Health 2011, 10:78
- Kroesen and Schreckenberg. A measurement model for general noise reaction in response to aircraft noise. J. Acoust. Soc. Am. 129 (1), January 2011, 200-210.
- HGC Engineering, Low frequency noise and infrasound associated with wind turbine generator systems: A literature review. Ontario Ministry of the Environment RFP No. OSS-078696.
- Bob Thorne. The Problems with “Noise Numbers” for Wind Farm Noise Assessment. Bulletin of Science Technology and Society 2011 31: 262.
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Dec 15 2011
Human impacts, News, Wind turbines No Comments »
The Pinnacle Wind Farm in West Virginia has been gearing up in recent weeks, with all of its 23 turbines to be spinning by the end of the year. But even as the wind farm began initial operations, neighbors have petitioned their county commission to request that the state PSC require the turbines to be shut down from 10pm to 7am.
Richard Braithwaite, who lives three-quarters of a mile from the nearest turbines, says that he he “never would have believed they would make that much noise.” He told the commissioners, “If you turn the turbine one way, it sounds like a railroad train. If you turn it another way, you hear the whine. The noise wakes me up; I can’t sleep. It’s so loud … you can’t drown it out with the television or anything.” He says a simple sound meter has shown levels of 60dB and more inside his home on most nights (ed. note: it’s possible that this included other sounds); the wind developer has done some sound monitoring recently as well, though the results have yet to be released; the company has also sent a representative to visit with neighbors this week.
For more on this unfolding situation, see: Mineral Daily News Tribune article, Cumberland Times-News article.
Dec 09 2011
Dec 05 2011
Default No Comments »
The Umatilla County Commission approved construction of a 33-turbine wind farm, rejecting a citizens’ challenge of the recent OK given by the County Planning Commission. In June, Umatilla County enacted a 2-mile setback provision for new wind farms, but the Chopin Wind Project application was submitted in April, so was not subject to the new rules. The 2-mile limit is at least twice that used in other Oregon counties.
The County says the Chopin Wind Project, which will be built using 3MW turbines, will be subject to Oregon’s state noise standard of 36dB; another Oregon county recently decided not to enforce this limit (the state delegated enforcement to the counties years ago). The 36dB limit tends to lead to setbacks of about a half mile or so, depending on terrain and other factors used in modeling likely sound propagation.
Dec 02 2011
Effects of Noise on Wildlife, Wind turbines 2 Comments »
Jane and Julian Davis’ long-running dispute with a wind farm located 1km (just over a half mile) from their home in Deeping St. Nicholas has come to an end. On the day before their case, seeking either a permanent shut-down of the wind farm or 2.5 million pounds in damages, was due to hear the final witnesses at London’s High Court, a settlement was announced between the Davis’ and the wind farm developer. The details of the settlement are confidential, and likely less than the Davis’ were seeking, but we can likely presume that it is enough for them to buy another piece of rural property; they moved out of their home less than a year after the wind farm began operation in 2006. Update, 12/6/11: a local newspaper talks to the couple.
The settlement comes as somewhat of a surprise, considering the vehemence with which their claims of being forced from their home were challenged in the first round of testimony at the High Court this summer. However, a spokesman for Renewable UK, the wind energy trade association, welcomed the news of a settlement, saying that the organization always encourages its members to work closely with local residents when planning projects to ensure that any local issues are resolved without ending up in court.
To which I might say, they were a bit behind the curve this time! Yet certainly the industry would prefer to not risk negative court judgments in a high profile case such as this, which was the first such challenge to a wind farm on basis of a “nuisance” rather than as violating specific wind farm operational guidelines. This settlement is but the latest of quite a few situations in which wind developers felt it made more sense to buy property or otherwise settle disputes financially than fight nearby neighbors who had moved out of their homes or were prominent local voices about the noise impacts of siting choices. (That spree of links reflects buyouts in Ontario, Washington, Oregon, and Australia.) While the prospect of purchasing property is often said to introduce untenable uncertainty into project financing, the actual cost of purchasing a few nearby properties is dwarfed by the cost of the turbines themselves (over a million dollars each). Most of these settlements have been concessions by developers after problems arose, though in at least one Australian case, the buyouts were presented as a “sell your house or live with it” option prior to construction, which neighbors felt was an untenable and unfair choice.
There is clearly movement here, in that developers are recognizing that impacts are more dramatic on some neighbors than on others, and than had been expected. Yet we also clearly have a way to go before we can say that dialogue on these variable impacts has become routine or an influence on setback distances proposed by developers. So far, we’ve yet to see any developers take the proactive approach of agreeing to keep turbines well away from unwilling neighbors, and to work with willing neighbors or willing sellers to come up with a viable site plan. That time is not far away, though, I suspect; the industry will surely benefit from reducing the contention that results when site plans lead to significant audible noise impacts on unwilling neighbors.
Nov 30 2011
Effects of Noise on Wildlife, News, Ocean, Wind turbines, shipping No Comments »
For the first time, an onshore wind farm has triggered calls for caution from marine mammal protection organizations. The 2500-acre, 56-turbine wind farm will be built along a steep shoreline that funnels nutrient-rich waters from Antarctica to the surface, spawning a dense aggregation of phytoplankton and krill. Along the coast of Isla Grande de Chiloé, blue whales and right whales gather from January to April to feast on this abundance; blues come as close as 400m to shore, and rights have been seen only 5m offshore.
Environmentalists, including local organizations like Santiago’s Centro de Conservación Cetacea, and international voices such as the Whale and Dolphin Conservation Society have raised dual concerns, regarding construction of a new port to bring construction materials to the site, vastly increasing ocean noise from ship engines in this relatively acoustically pristine area, and possible disturbance or even displacement of animals due to noise from pile driving during construction and airborne wind turbine noise during operations. Even the International Whaling Commission’s scientific committee has called for ”the urgent development of an environmental impact assessment in this region and to reconsider locating the wind farm towers further away from coastline.”
The importance of the feeding ground to southern hemisphere blue whales, combined with having 40% of the turbines right along the shore, raise the question of whether the ongoing blade noise will keep whales at a distance; there is some evidence that airplane overflights cause whales to move away, and the sound levels of the turbines will be similar to a small plane. Whether whales might be able to move a small distance away and still find enough krill is the big question. Chile’s environmental authorities approved the project in August after requiring a simple environmental declaration, rather than a detailed impact study; the Chilean Supreme Court is hearing a lawsuit from opposing groups, and will make a decision in the next few months.
National Geographic News has a good, detailed article on these questions.
Nov 21 2011
Human impacts, Wind turbines No Comments »
An article in the Independent this week details the steps taken by four English wind farms to reduce noise experienced by neighbors. In each case, the wind farm operator made changes in at least some turbines’ operation, including slowing them down or shutting them off when the wind hit certain speeds or came from directions that heightened the problems.
Nov 16 2011
Bioacoustics, Effects of Noise on Wildlife, Science, Wind turbines No Comments »
Research summary of Francis, C.D., Ortega, C.P., Cruz, A. 2011. Noise pollution filters bird communities based on vocal frequency. PLoS ONE 6(11):e27052.
An ongoing research project in New Mexico continues to shed more detailed light on the question of how moderate human noise affects nearby wildlife. In a study design that effectively separates out the impact of the noise from other habitat disruption effects, Clint Francis and his colleagues are finding that some species are displaced, while others seem to thrive in areas with coalbed methane compressor stations creating noise around the clock. The most recent paper to be published by Francis et al finds that species that sing at lower frequencies are most likely to avoid the noisy areas, while those who vocalize at higher frequencies are more apt to be unaffected or even thrive.
While this research studies an area with oil and gas development noise, it’s likely that similar effects would occur in and near wind farms, which also produce predominantly low-frequency noise. And, as the authors note to conclude their paper: “At the community-level, we must still determine whether noise is an agent of ecological filtering for other taxa that rely on acoustic communication.”
Rather than doing the full AEI lay-summary of the most recent paper, I want to point you to the great summary already written by Caitlin Knight, biologist who studies the ways in which anthropogenic disturbance impacts animals, on her Anthrophysis blog.
Nov 15 2011
Human impacts, News, Wind turbines No Comments »
Town officials from Mount Pleasant, Wisconsin recently visited a wind farm in Brownsville in order to listen and take sound measurements of turbines similar to three being proposed by a local plant that aims to generate all its energy needs on site.
What they heard reassured them, after hearing noise concerns from some local residents. ”At 800 feet, measurements came in at 46 - 47 decibels, and at 1,200 feet it was less than 40 decibels, ” said Planning Director Ron Meyer. By comparison, he said a passing car on the paved road came in at 62 decibels. Even within a thousand feet, they could sometimes not hear the turbines spinning.
Of course, any quick visit to a wind farm offers just a snapshot view (or listen). In many cases, neighbors’ noise issues occur mainly in particular atmospheric or wind conditions, so the question becomes how common these above average noise events are. Stable sound-reflecting air layers above the turbines, high levels of turbulence in the air hitting the blades, and wind speed differences from the bottom to top of the blades are all factors that tend to contribute to higher or more intrusive noise levels. And, night time noise tends to be a bigger issue than day time; even moderate noise levels can become the loudest sound heard out a bedroom window at night.
Still, it’s good to get out there and get a sense of what may be heard near the proposed turbines. Unfortunately, no residents were able to join the town officials on this trip, though they were invited. It’s hard to know what degree of investigation will really give a complete picture of what may be experienced by people near the plant; spending a few nights in Brownsville might help. More generally, many towns considering wind project siting questions would be well served by a series of well-designed survey projects around wind farms, which might best capture the range of experiences at existing wind farms.
Nov 15 2011
Human impacts, News, Wind turbines No Comments »
A couple living roughly 5000 feet from a proposed 5-turbine wind farm has appealed the project’s approval by the town of Clifton, Maine, citing quality of life concerns due to the likelihood that they will hear the turbines from their home and farmlands. “Our land is our home. We work here. We farm here. We recreate here and we restore our souls here,” said Peter Beckford. Beckford and his wife Julie run an organic flower business on a sixty-acre property, which also includes several small cabins where farm apprentices and other visitors live.
The proposed wind farm, on Pisgah Mountain, was designed to include 4000-foot setbacks from homes, but the Beckfords say that their cabins and other buildings used for their business were improperly excluded as protected or occupied structures when the setback was applied.
The Beckford’s challenge is notable in that it is making a quality of life argument that audible turbine noise is an inappropriate addition to the local soundscape. The appeal rests on several permitting issues, including the outbuilding distance and other aspects of the town’s planning process, but their statements indicate that the turbine noise is the crucial issue for them. Their challenge is perhaps the strongest expression yet of the feeling by some rural residents that any noise intrusion is unacceptable; several more cautionary acousticians have recommended noise limits, at least at night, of 30-35dB, and setbacks of a mile to a mile and a half, in acknowledgement that any turbine noise readily audible above quiet rural background sound levels will trigger significant annoyance in some neighbors.
Most previous challenges of wind farm approvals have attacked siting standards that placed turbines much closer than a half mile, or noise standards that could allow intrusive sound levels (15dB or more over ambient) at some or many homes. In saying that three-quarters of a mile is not far enough away, the Beckfords are standard-bearers for rural residents who want wind farms to be far enough away to be effectively inaudible. For people living deep in rural areas, it’s an understandable desire; some towns have have banned tall industrial turbines altogether, to assure local soundscapes will remain unblemished. Other towns, aiming to be somewhat more welcoming to wind projects, have set half-mile to 4000-foot setbacks in order to reduce the severity and frequency of noise intrusions. Time will tell whether new wind farms built with these larger setbacks will be more easily accepted by rural communities.
Nov 09 2011
Human impacts, News, Wind turbines No Comments »
A wind farm in South Australia has been shutting down 16 of its 34 turbines at night since last December, after a nearby neighbor complained of noise keeping his family awake at night. This week, the state Supreme Court affirmed that the wind farm was breaking its noise limit, due to a tonal noise component, and sent the issue to the Environmental Resources and Development Court for adjudication.
The neighbor, Bill Quinn, said his mother and sister, who live near the existing turbines, had been in “absolute heaven” since the decision was made to shut the turbines down at night. A spokesman for AGL Energy said that ”We understand that one of our neighbours has been inconvenienced and we apologise. We want to be a good neighbour and we’re committed to working with local communities and taking any concerns that they have about our projects seriously.” AGL is working with the turbine supplier on a “permanent acoustic treatment” to dampen tonal noise.
Several Australian states have recently moved to increase setbacks from new wind farms. In Victoria, the Baillieu government has announced strict regulation of wind farm developments, including a minimum 2km (1.25mi) distance from houses. In NSW, Premier Barry O’Farrell has indicated he intends to introduce similar laws. South Australia’s guidelines limit noise to 35dB in areas “primarily intended for rural living” and 40dB elsewhere, while providing for agreements with landowners to allow higher sound levels.
Nov 09 2011
Human impacts, News, Wind turbines No Comments »
Town votes in Riga, Michigan, and Rumford, Maine have both adopted wind farm siting standards that are somewhat more cautionary than most. Riga township voted 440-236 to uphold an ordinance that establishes setbacks of 4x turbine height (1200 or so feet) from non-participating property lines, and sets a noise limit of 40dB at night and 45dB during the day. The distance setback shouldn’t be an issue for developers (1200-1500 foot setbacks are typical of many wind farms), though the night time noise limit could make it difficult to site turbines closer than a third to half mile from homes. It wasn’t clear from initial press reports whether the Riga ordinance provides an option for neighbors to sign waivers allowing closer siting or higher noise levels.
Meanwhile, the third time was the charm in Rumford, where two previous proposals went down to defeat, one for being too stringent (including setbacks of a mile), and the next for not protective enough (the sticking point likely being a 45dB night time noise limit). The current proposal garnered overwhelming support, winning by a margin of 1137-465, and includes a 40dB night/50dB day noise limit, along with a 4000-foot setback from non-participating neighbor property lines. Neighbors can, however, sign a Mitigation Waiver agreement to allow closer siting.
Conversely, in New Hampshire, Read the rest of this entry »
Oct 30 2011
Human impacts, News, Wind turbines 2 Comments »
I’m traveling this week, so not monitoring the news on a regular basis, but tonight I thought it would be useful to simply highlight a few news items that came through my custom Google News section on wind farm noise in the past few days. The mix of stories is pretty typical of what occurs each week:
Representing the widespread efforts of local planning authorities to make sense of conflicting voices are two towns, one near the end of its process, and one still close to the beginning. Supervisors in Palmyra Township in Michigan (right) decided to rescind an earlier tightening of their noise and siting regulations, after a wind developer said the rules as adopted would likely prohibit construction in the town. In a 3-2 vote, the majority were concerned about such a prohibition, agreeing with Supervisor Dale Terry, who said, “I’m not sure that is fair or proper,” while one joined with Steve Papenhagen, who stressed that “I don’t know how we can force this on landowners that don’t want to be a part of it.” The Supervisors re-established a noise limit of 45dB at buildings on neighboring properties, up from 40dB in the previously amended plan.
In Frankfort, Maine, where a four-to-six turbine project is planned, a community meeting on a proposed wind farm ordinance got heated, culminating in a shouting match between a developer and an anti-wind activist outside the building after the meeting ended. (Apparently, they embodied the state of our current dialogue to perfection, each yelling that the other was a liar!) A committee that had developed a draft ordinance presented it at the meeting; they proposed a 1-mile setback, and noise limits of 45dB during the day and 32dB at night, measured at neighboring property lines. State regulations currently call for 55db during the day, and a recently proposed 42dB at night, measured at homes. Josh Dickson, who served on the committee, noted that noise heard at homes, especially at night, can cause insomnia and hypertension, according to their findings. “At the end of the day, this is research. It’s not perfect. Neither are we,” Dickson told the crowd. “We did the best we can. The decision will be up to you guys, not us.” The small wind developer planning the project, Eolian Renewable Energy, is proposing a setback of three times the height of the turbines, or about 1000 feet, and also calls for using the state noise limits.
A woman from Freedom, Maine, spoke at the Frankfort meeting, and shared an unusually clear and poignant story of noise impact at their home, 3000 feet from one of several turbines. Her three kids have all been prescribed sleeping pills due to wakefulness since the turbines began operating; this strikes me as particularly noteworthy, since the kids are less likely to be affected by pre-existing concern or fear, which some blame for the reports of sleeplessness and stress in adult wind farm neighbors.
In North Devon, England, the Fullabrook wind farm (left) is gradually becoming operational, with all turbines planned to be spinning by the end of November. Several neighbors have noted that noise has been a problem as the wind farm begins to ramp up. Sue Pike’s bungalow is 600 meters (about 2000 feet) from one of the turbines at the new wind-farm and she says: “It is dreadful – the main sound is like a huge great cement mixer going around – then you get the loud whoosh and also whistles and hums. Altogether we have counted four different noises coming from it. Back in the warmer weather when the turbines were being tested we couldn’t open the bedroom or lounge windows – fortunately we are double-glazed so that helps cut out the noise – but we were stewing indoors.”
The wind developer in Devon, ESB, will begin noise monitoring once the wind farm is fully operational. ”ESB will continue to work closely with the local community – particularly our immediate neighbours and North Devon Council – to ensure we not only meet all conditions of the planning permission, but that we are able to discuss local concerns and take what measures we can to address issues,” commented a company spokesman. North Devon Council’s Environmental Health Department will also conduct site analysis at five locations in response to residents’ concerns.
On the other side of the coin, Barnstaple town councillor and Green Party member Ricky Knight visited a friend’s house near the wind farm (though the distance wasn’t specified), and said, that ”essentially all we heard was the wind, birds and farm machinery. I was not able to discern any sound coming from the turbines. I am in receipt of criticisms (from people who don’t like the wind-farm) but I get far more support from people who simply register confusion about this subject.”
While it’s quite common to hear from wind farm supporters who were surprised and dismayed by the noise levels they encountered once the turbines were operating, we hear the opposite tale from Leicestershire, UK. There, after living for seven months with a new wind farm, some opponents are saying it’s not as bad as they feared it would be. The article quotes two former objectors and one wind turbine host and doesn’t specify many distances, but one farmer “less than a mile” away says ”I went to all the protest meetings and I was against them from the start. But now, I must say they don’t really bother me. I can’t hear them and I can barely see them. It’s like the industrial revolution all over again – people don’t like change until it actually happens and they get used to it.” This could be a simple case of people a fair distance away being more worried than they needed to be; a quick search online didn’t come up with news reports of problems from other (closer) residents, but it may be too early to assume there are none, especially since they’ve yet to go ’round all the seasons.
Knight’s experience in Devon, as contrasted with Pikes, is a great illustration of the disconnect that continues to dog wind farm development and ordinance-writing. I think we can safely assume that Pike’s not imagining the sound that’s bothering her, and that Knight visited at a time and place where the turbines were inaudible (and it must have been daytime, since farm machinery was operating). Complicating the challenge before town boards is a widespread uncertainty about who to trust; as noted by Palmyra Supervisor Jim Isley, “I have to wonder sometimes if one side doesn’t exaggerate their claims, and the other side perhaps doesn’t tell all that they know.” Indeed, AEI’s continuing attempts to make sense of the polarized rhetoric coming from the two sides suggest that both tend to overstate their case. Developers often downplay potential noise issues; for example, the Eolian website lists typical rural sound levels at 40dB (probably a 12 or 24 hour average), while night time sound levels in deeply rural areas are often measured as low as 20dB, so that a turbine may become a truly dominant sound. Meanwhile, community groups tend to assume that the worst-case responses they hear about elsewhere will be common, even at great distances. For example, a letter published this week about a proposed wind turbine at a gravel plant in California, expressed concerned that a school is “only 1.5 miles away.” The letter claims that Oregon requires a two-mile setback (they don’t: though their noise limit is one of the lowest, 36dB, setbacks tend to be in the half-mile to mile range). Even many more cautionary acoustics experts, who tend to favor noise limits of 30-35dB, suggest that 2km (1.25 miles) is a reasonable minimum setback, with some recommending a mile and a half; the gravel plant turbine doesn’t appear to be close enough to warrant alarm or heightened concern. We clearly have a long way to go before we can have a clear, reasoned discussion about whether current setback standards are providing a degree of community noise protection that’s similar to that we’ve become used to from other noise sources.
Oct 30 2011
Oct 17 2011
Health, Human impacts, News, Wind turbines No Comments »
A brief article from a local paper in Illinois shed some new light on two key issues that have come up in many communities considering new wind farm proposals. The meeting of the Lee County Zoning Board of Appeals featured an hour-long presentation from Carl Phillips, an epidemiologist who has published a peer-reviewed study saying there is “overwhelming evidence” of health effects near turbines. He said that people up to two miles away have reported health issues such as sleep and stress issues and mood disorders. When asked what percentage of residents report health problems, he said that there have not been solid studies of that, but that his best guess, based on what research has been done, is about 5 percent of those within a mile or so. This relatively low estimate may surprise some, but such reports from many wind farms lead Phillips to conclude that anyone denying health effects exist is ignoring the evidence or “trying to mislead.” And, even this low estimate was challenged by representatives from Mainstream Renewable Power, who characterized Phillips’ presentation as “personal hypotheses.” (Ed. note: the continuing effort of industry representatives to discredit suggestion of any problems at all, including Phillips’ modest 5% estimate, or recordings that reflect higher levels of sound or amplitude modulation than expected, has become a major impediment to constructive engagement on wind farm siting decisions; ongoing diligent study by more cautionary experts deserves to be given more credence.)
In addition, the mayor of the village of Lee asked representatives of Mainstream whether confidentiality agreements signed by landowners leasing land for turbines will prevent them from discussing any health problems that they may notice once the turbines are operating–reflecting a widespread concern that health problems may be under-reported due to such agreements. One Mainstream rep spurred laughter from the audience when he said he couldn’t talk about what the confidentiality agreements address, since they’re “inherently confidential.” But another Mainstream rep stressed that the agreements do not preclude talking about health. (Ed. note: Many confidentiality agreements with landowners are primarily designed to keep financial details private; this is especially true when a house is bought by developers.)
Oct 14 2011
Wind turbines 3 Comments »
For the past three years, I’ve been learning what I can about the ways that wind farm noise affects nearby neighbors. While most online information tends toward the black-and-white—the sound levels are lower than most human noise sources and current siting standards are fine; the noise is invasive and we need to totally rethink the efficacy of wind energy—AEI has been dedicated to fleshing out the shades of grey. A noise that drives one person crazy is considered a gentle whoosh by another; ranching areas tolerate wind farm noise at levels far above those that are causing problems in rural areas where residents especially value peace and quiet; community noise standards that minimize complaints about, say, road noise, can appear to be too high for wind farms. As important as it is to tell the whole story, including the fact that much is yet unclear, I feel a bit adrift in the grey these days. When it comes right down to it, how does one describe a shade of grey?
In the coming months, AEI is going to take a different approach. More to the point, I’m going to focus my energies toward a different purpose, a new task. Rather than trying to “tell the story” in a way that helps everyone see the issue from a larger perspective, I’m going to use my time and energy to put together a toolkit aimed at providing the necessary information to allow anyone to come to their own conclusions: an annotated collection of concrete information about the sound levels and varied community responses observed around wind farms. Given the limits of what one person can do, it probably won’t be totally comprehensive, but it will draw from the full spectrum of researchers and experiences, and will attempt to provide some context to understand what is known, what is mostly unknown, and where we might most fruitfully direct further investigations.
I think that AEI’s publications over the past couple of years have done a fairly decent job of telling the big-picture story of wind farm noise. The various presentations, articles, and reports have taken different approaches toward a common goal: to explore the paradoxes and subtleties that belie both the black and the white views.
Read the rest of this entry »
Oct 10 2011
Human impacts, News, Wind turbines 12 Comments »
The wild and turbulent public debate about wind farm noise issues continues to generate steady new eruptions in Ontario. And while what’s coming out could be extremely valuable information for others struggling to support a more cautionary approach to wind farm siting, media reports are contributing to an increasingly jumbled public perception about the troubling health impacts that some wind farm neighbors have experienced.
Ironically, the spotlight currently shining on Ontario could be shedding a clear, focused light on the shortcomings in current siting standards – even Ontario’s relatively stringent ones. That light would reveal regional regulatory staffers raising concerns about whether the standards as currently applied are in fact protecting residents from undue disruption by wind farm noise, increasing anecdotal evidence from homeowners and realtors that wind farms make it harder to sell homes at their fair value, and telling examples of homes bought at market value by wind developers and later sold at large losses. Instead, these important and fascinating stories are being jumbled into a far less coherent mess of public perception, with negative health impacts becoming the dominant theme. (See the final paragraphs of this post for AEI’s prescription for moving forward more constructively.)
As real as the health effects can be — there’s no doubt that some nearby neighbors have struggled mightily with them, to the point of leaving their homes to find relief — it doesn’t serve the public to conflate every noise complaint with a health complaint, or to distort the sources of noise complaints to make the suffering of the most afflicted appear to be far more widespread. This is, unfortunately, the effect of recent media reports from Ontario, Read the rest of this entry »