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French court orders wind turbines shut off at night

Human impacts, Wind turbines 2 Comments »

In early December, the Association for the Protection of Ménez, Quelec’h and Saint-Gildas won a groundbreaking court case in France, in which the Court of Appeals of Renne ordered that eight wind turbines in Cast and Châteaulin be shut down from 10pm to 7am.  The Association had sought court relief from night time noise disturbance in the area around the wind farm.  News coverage is spotty: here is a brief summary of the case, and here is a French news story, crudely translated by Google.

See more AEInews coverage of wind turbine noise issues

Community wind project on Maine island faces noise issues collaboratively

Human impacts, Wind turbines 1 Comment »

It’s a beautiful idea, come to fruition: in the island communities of Vinalhaven and North Haven, Maine, a local electrical co-op joined forces with a regional nonprofit organization, and built three large wind turbines which would provide the 2,000 households on the island with locally-produced power.  On a lovely fall day in November, the largest group of island residents ever gathered in one place celebrated the commissioning of the Fox Islands Wind Project.  But for some residents, the moment they had been waiting for had an unexpected element: clearly audible noise.


“As I watched the first rotation of the giant blades from our deck,” says Sally Wylie in the island newspaper, The Working Waterfront,  “My sense of wonder was replaced by disbelief and utter shock as the turbine noise revved up and up, past the sound of our babbling brook, to levels unimagined. It was not supposed to be this way! During informational meetings, on the Fox Islands Wind website, in private conversations, and with personal correspondence, we were all told that ambient noise from the surrounding area would cover the sound of the turbines. This was our expectation….We have found that the 45 decibel limit that is designated as ‘quiet’ in Maine, is truly a cruel joke. On our quiet cove, we now know that 45 decibels is loud.”

The community came together to dream and build the turbines, and now they are working together as well to address unexpected noise issues.  Starting the day after commissioning, representatives of the wind project visited neighbors, deployed microphones, trained neighbors in how to record sound and wind speed, and asked neighbors to keep diaries of their experience of the noise.  Also writing in The Working Waterfront, board members of the local electric co-op and the Fox Island Wind LLC, formed to take advantage of tax credits available for wind development, affirm  that they are “committed to monitoring the sound impacts beyond the traditional approach of measuring wind speeds and decibel levels, as we have asked neighbors to also document their subjective experiences so that we can determine any other factors they may be finding bothersome. In a wide variety of ways, the Fox Islands Wind project has been a very different, first-of-its-kind, model wind project. We are committed to dealing with the sound issue in the same open and participatory way that we have approached the project since its inception.”

Once again, the experience of people on the ground, and initial recordings and conversations with neighbors, suggests that the noise is most troublesome within a half mile of the turbines, with some lesser effects out to a mile or more. According to Fox Islands Wind, “it does not appear that, except in a few individual spots, there is much impact beyond a half mile from the site.”  Wylie’s conversations and recordings suggest to her that “households within a mile to a mile-and-a-half radius of the turbines are impacted by the sound.” The commentary here at AEInews is beginning to sound like a broken record, but here we go again: it is clear that we will need to make some social choices about the degree of disturbance we are willing to trade for the benefits of renewable wind energy.  There is little doubt that homes within a half mile of turbines often experience elevated noise levels, and beyond that distance, impacts diminish in frequency and severity.  Where will we decide to draw the line?

Fox Islands Wind Project website

The Working Waterfront, visit for ongoing coverage of the story

Island Institute community energy web info, including article on offshore wind and column in Working Waterfront on the genesis of the Fox Islands Wind project, including its economic justice/equity goals.

Wind industry study says no health effects – but omits any mention of sleep disruption

Health, Human impacts, News, Science, Wind turbines 5 Comments »

Download a Word doc version of this commentary

A report issued by the American Wind Energy Association (AWEA) and the Canadian Wind Energy Association (CanWEA) purports to assess all currently available research on the health effects associated with exposure to wind farm noise, and concludes that there are no such problems.  The report, funded by North America’s two key wind industry trade organizations, centers on the symptoms of the reported “wind turbine syndrome,” and while it offers a robust critique of the idea that low frequency noise from wind farms can cause direct health impacts, it’s hard to take its message of wind’s “clean bill of health” at face value, thanks to many topics that are ignored or underplayed.  The report minimizes the levels of annoyance and impacts on quality of life reported in other studies, and completely omits any assessment of the most widely reported health-related impact of living near wind farms, sleep disruption. (For more complete assessments of health-related issues related to wind farms and noise, see recent reports from the Minnesota Department of Health report and World Health Organization.)

The authors of the new AWEA/CanWEA report acknowledge that some people may be annoyed by the sounds of wind turbines, but stress that annoyance is not an “adverse health effect.”  They also seem intent on assuring that any mention of annoyance rates is kept to 10% or below, which necessitates some creative re-interpretation of one of their key sources, a recent paper by Eja Pederson that compiled results from three surveys near wind farms in Scandinavia, summarized in October by AEI. In particular, they combine results from two studies in rural areas and one in a suburban area, which Pederson explicitly presented separately, because they illustrate that annoyance rates are far higher in rural areas (since the suburban study had more participants, the overall average is dominated by the suburban results).  In AEI’s view (as regular readers will know), the bottom line in all annoyance studies is that while many (or even most) people who are within earshot of wind turbines are not strongly affected by the noise, a substantial minority (ranging from 5-40% depending on how close they live) are negatively impacted, sometimes to the point of abandoning their homes; our challenge is to decide how many people we feel OK disrupting, and regulating wind farm siting to match that choice.

The report also repeatedly states that “the sound emitted by wind turbines is not unique,” while it elsewhere briefly acknowledges the often fluctuating nature of turbine noise (amplitude modulation) and its role

Read the rest of this entry »

NPS study: moderate noise can have major impacts on animals

Animal Communication, Bioacoustics, Effects of Noise on Wildlife, Science, Vehicles, Wildlands 3 Comments »

An ongoing research project from the National Park Service Natural Sounds Program is about to publish a groundbreaking paper that outlines the many ways that even moderate increases in human background noise can create major impacts on animals.  The study proposes a new metric for use in bioacoustics research, the “effective listening area.”  This is the area over which animals can communicate with each other, or hear other animals’ calls or movements; as might be expected, animals focus especially on listening for sounds at the very edges of audibility, so that even a small increase in background noise (from a road, wind farm, or regular passing of airplanes) can drown out sounds that need to be heard.  The authors note analyses of transportation noise impacts often assert that a 3dB increase in noise – a barely perceptual change – has “negligible” effects, whereas in fact this increased noise reduces the listening area of animals by 30%. A 10dB increase in background noise (likely within a few hundred meters of a road or wind farm, or as a private plane passes nearby) reduces listening area by 90%.

In addition to introducing this important new metric, the paper provides a good overview of previous research that has addressed the impacts of moderate noise on various animals, including bats, antelope, squirrels, and birds.  The paper will be published next year, though an “in press” version is available for download.  A recent BBC article also covered this important new work.  A full detailed lay summary of this paper, as previously published on AEI’s science research page, appears below the fold: Read the rest of this entry »

“Worst case” wind turbine noise may occur 30% of summer/fall nights

Wind turbines Comments Off on “Worst case” wind turbine noise may occur 30% of summer/fall nights

A study by a retired NY State Department of Environment staffer has found that in one community where two new wind farms are planned, “worst case” atmospheric conditions can occur up to 30% of nights in summer and fall, peaking at over 40% of nights in early summer.  The wind farms in Cape Vincent are moving forward in the permitting process based on noise modeling submitted by the wind developers, which predicts minimal impact on neighbors thanks to an average background ambient noise level of 45dB.  This study found that on nights with little wind at ground level, actual ambient sound in this rural area is generally below 35dB, and in many areas, drops to 25dB or lower for much of the night.  Also, and most importantly, the study used standard predictive measures (including wind differential at two near-ground heights, daytime solar radiation, and night time cloud cover) to estimate how often the winds at turbine hub height would be high enough to turn the turbines on, even as the wind at ground level remained low – the situation that often triggers the worst night time noise complaints near wind farms.  The sobering result was that such nights, which create noise issues for neighbors far beyond those predicted by the simpler noise modeling used during permitting, could be a regular occurrence for most of the summer and fall.  After taking noise measurements at a wind farm currently operating in a nearby town – which found levels similar to those predicted and allowed in current Cape Vincent planning – the author notes that the vast majority of Cape Vincent homes will be close enough to hear the turbines easily on these “worst case” nights, with a third  of local households likely to experience objectionable noise levels.

It is important to note that these levels of audibility and possibly objectionable sleep disruption will still occur on a minority of nights; indeed, on an annual basis, only  around 15% of nights. And, on those nights, just a portion of the population (those closest to the turbines) will be affected. This perspective is part of what has led to our current acceptance of relatively small setbacks from homes (often 1000-1500 feet). Our social decisions about wind farm siting will need to grapple with the question of how much disturbance we consider acceptable – in this case, a third to half of the residents of Cape Vincent may be looking at troubling noise levels for a third to half of summer and autumn nights. To protect most residents from most of the noise intrusions (by keeping noise levels to 5-10dB above the true local ambient level) would require setbacks of 1km or so (between a half and three-quarters of a mile), which would likely limit the Cape Vincent area to more like 30-50 turbines, rather than the planned 200.

Click on to go below the fold and read a more detailed summary of the research paper, which first appeared on AEI’s new science research page. Read the rest of this entry »

Undersea mining: moving forward at last? Too fast?

News, Ocean, Science Comments Off on Undersea mining: moving forward at last? Too fast?

The mining industry is looking more actively at the vast opportunities available if they can tap into the three quarters of the earth’s surface that is under the oceans.  A new generation of undersea technology, developed in part by the oil and gas industry, is opening this door that was previously mostly a dream.  Undersea crawlers, remotely operated vehicles with robotic arms, and subsea processing units are all key to the new mineral rush that may be starting.  The Woods Hole Oceanographic Institute magazine Oceanus ran a good piece on the history and current plans in this realm; much of the focus has been on undersea vents, where biologists are concerned about impacts on rare species (extinct or dormant vents may have the minerals with far less active communities of life).  Meanwhile, the International Maritime Minerals Society has released a new draft of its Code for Environmental Management of Marine Mining, and is accepting comments through April 15, 2010 (email to Verlaan AT hawaii DOT edu).  The draft code has some fairly progressive provisions, including leaving corridors to facilitate biological re-establishment after mining, and leaving nearby similar areas untouched to serve as research/environmental controls; the code makes no mention of assessment of the noise footprint of mining, which is bound to be locally significant.

Bias in Military (or Conservation) Funded Ocean Noise Research

Ocean, Science, Seismic Surveys, Sonar Comments Off on Bias in Military (or Conservation) Funded Ocean Noise Research

(this item first appeared in AEI’s lay summaries of new research)

Wade, Whitehead, Weilgart. Conflict of interest in research on anthropogenic noise and marine mammals: Does funding bias conclusions? Marine Policy 34 (2010) 320-327.

In the United States, the US Navy funds about 70% of the research into the effects of ocean noise on wildlife (and half, worldwide). For many years, conservation groups have questioned whether this preponderance of funding is skewing research results, whether by constraining the types of questions being studied, or by leading researchers to downplay negative impacts of noise in order to continue receiving funding. The authors of this new study report a significant correlation between Navy funding and results reporting “no effect” of noise, based on their analysis of  several wide-ranging reviews of ocean noise science, and of the primary research papers cited in these reviews.  While the data behind their conclusion is clearly explained, the results don’t look nearly as clear-cut to me; I question the comparability of the five reviews used, and while the trends in primary papers is more obvious, it’s hard to ignore the fact that the majority of military-funded papers still found that noise had effects.  Indeed, as the authors make clear, it’s the conservation-funded reviews and primary research that is most clearly one-sided in its results (though there are good reasons for this, also fleshed out by the authors and in AEI’s commentary below).  In AEI’s view, studies like this – and indeed, reviews such as those considered here – are diligent exercises in quantifying an issue that has become, for all practical purposes, an exercise in divergent world views and beliefs talking at and past each other.

This post includes more analysis and interpretation by AEI than we generally include in our science summaries; it’s a long read, but the issues that triggered this study are important ones. Though the clear-cut results reported here are difficult to take at face value, it is well worth considering the underlying forces that drive tensions between environmental groups and Navy/industry actions in the seas.  While primary research and even literature reviews funded by the military don’t appear overly biased toward finding no effect (since in both cases, they include far more results showing effects than not), it remains that in practical terms, the EIS’s generated by the Navy and the mitigation measures imposed by regulators on both military and oil and gas activities are largely grounded in the belief – and regulatory determination – that any effects of these activities are “negligible,” to use the formal term. Thus the focus of the conservation community on funding research and publishing overviews that emphasize credible studies outlining observed negative effects is understandable.

Of special note is that the authors did not find any strong trend toward bias of results reported by independent, academic researchers receiving Navy funding for research studies – these studies showed a similar proportion of effect and no effect results as studies funded by neither the military nor conservation groups (though when comparing military-funded studies with all the others, including consevation-funded, a non-statisticially significant trend of 1.64 times more “no effect” findings was observed).  This should diffuse widespread concerns that cash-strapped academic researchers are “cooking the books” or avoiding publishing negative findings in order to retain Navy funding (though it is perhaps unsurprising to note that few if any key Navy-funded scientists are among the researchers who are willing to speak out publicly to push for stronger regulations on ocean noise). The authors conclude that “much of the bias in military-funded research was in work carried out at military institutions, rather than in studies funded by the military but carried out at universities and other institutions.”  Thus, research coming directly out of military offices is likely to remain less reliable as representing “the whole picture,” as may research entirely funded by conservation groups. Still, by integrating and considering the full range of studies reported in all of these reviews, the public can get a pretty decent picture of current state of our understanding of the effects of ocean noise.

Of note, though, is that the proportion of “no effect” to “effect” findings is slightly lower in military-funded studies. In addition, military-funded studies are three times as likely to report BOTH effects and lack of effects in a single paper; this could indicate either a more careful assessment of the margins where effects are just noticeable, or a tendency to split the difference in order to either underplay the effects or accentuate the non-effects to assuage funders.

While ocean noise issues came to public awareness after a series of stranding deaths and lawsuits, the fact is that deaths and injuries caused by noise are very rare.  Even the leading environmental activists have shifted their focus, and today nearly all of the controversy over military and oil and gas noise boils down to differing interpretations of how important moderate behavioral changes are, and whether they should be avoided or not. And science is nearly incapable of shedding any definitive light on how important behavioral changes are, thus leaving the two sides largely reliant on their divergent faith: the Navy and oil industry’s faith that the behavioral changes are transient and negligible, and environmentalists’ faith that chronic behavioral disruption by human noise is bound to have negative consequences. Meanwhile, ethical questions about humanity’s relationship to the natural world are outside the bounds of discussion on one side, and central to the whole discussion on the other.  This is not as black and white a picture as either side may paint, but it’s where we are.

For AEI’s full summary and discussion of this important new study, dive in below the fold…..

Read the rest of this entry »

Offshore Wind Turbines: More Evidence That Impact Area on Dolphins is Small

Ocean, Science, Wind turbines Comments Off on Offshore Wind Turbines: More Evidence That Impact Area on Dolphins is Small

(this item first appeared in AEI’s lay summaries of new research)

Tougaard, Henriksen, Miller. Underwater noise from three types of offshore wind turbines: Estimation of impact zones for harbor porpoises and harbor seals. J. Acoust. Soc. Am. 125 (6), June 2009. 3766-3773.

Underwater noise was recorded from three different types of wind turbines in Denmark and Sweden. The authors note that virtually all airborne noise from the turbine blades is reflected off the surface of the water, while vibrations from the machinery are transmitted through the tower and into the foundation, from where it radiates out into the water column and seabed. In general, turbine noise was only measurable above ambient noise at frequencies below 500Hz, with total SPLs of 109-127db re 1uPa rms, measured at 14-20m from the turbines’ foundations. By comparing measured sound levels with audiograms of harbor seals and harbor porpoises, the researchers determined that the sounds were only slightly audible for the porpoises at ranges of 20-70m, whereas harbor seals may hear the sounds at ranges of 100m to several kilometers. As a bottom line, researchers suggest that behavioral changes are very unlikely in harbor porpoises except at very close ranges, while seals may have some behavioral reaction out to a few hundred meters. For both species, masking is predicted here to be low to non-existent (due to differences between vocalization frequency patterns and the predominantly low-frequency turbine noise), and the sound is not loud enough to cause physical injury, no matter how close the animals are.

DOE study says wind farms don’t affect property values—but…

Human impacts, Science, Wind turbines 5 Comments »

A detailed statistical analysis of 5000 homes sold within ten miles of wind farms has failed to find any clear relationship between sales price and proximity to, or views of, industrial wind farms.  However, close reading of the results raises some questions about trends within a mile of turbines, and the authors recommend more detailed study of the closest homes as a top priority for future research.  Co-author Ryan Wiser affirmed that “It is possible that individual homes have been impacted, and frankly, I think it would be a bit silly to suggest otherwise. Human development impacts property values.”

As I look closely at the result, it seems likely that the apparent trend toward some property value effect largely mirrors surveys of residents near wind farms.  The “problem” in interpreting this data and the surveys is that there is NOT a universal increase in annoyance or sleeplessness or dropping property values as you move closer to turbines; rather, there is an increasing MINORITY of neighbors who are negatively impacted.  Several earlier posts address this factor: from 10% of neighbors at around a mile or so, increasing to 25% or so at a half mile, and perhaps 40% at a quarter mile, survey results reflect the well-known individual variability in susceptibility to noise.  It seems clear that the “small and infrequent” numbers of homes negatively affected in the study addressed here, are mostly concentrated near turbines, and may represent a similar percentage of landowners as report sleep disturbance and other noise impacts.  If so, the 5% average price hit is apt to represent a much larger valuation drop in a quarter or so of the homes that are within a mile.

The study, funded by the US Department of Energy at the Lawrence Berkeley National Lab, took into account size and other features of the homes, and looked particularly for any trends in prices resulting from views of wind turbines, having turbines in the vicinity (1-5 miles), and nuisance factors like shadow flicker and noise.  This third focus is the one of most interest to AEI, and we took a close look Read the rest of this entry »

NOAA sets beluga critical habitat, but says it won’t change Alaska’s urbanized Cook Inlet

News, Ocean, Shipping Comments Off on NOAA sets beluga critical habitat, but says it won’t change Alaska’s urbanized Cook Inlet

NOAA has released its proposed critical habitat for the endangered Cooks Inlet beluga population: it includes the entire upper part of the inlet (which includes Anchorage and Wasilla), and a coastal stretch of the lower part of the inlet as well.  This isolated population of belugas experienced a population crash in the 1980’s which is widely blamed on over-harvesting by native subsistence hunters, but has not recovered since the hunting was limited.  Pollution, limited salmon runs, and noise are all considered likely factors in the population’s struggle to survive.  Over the past few years, it has become apparent from field research studies and monitoring around seismic surveys that belugas are among the more sensitive cetacean species to sound; they tend to avoid noise sources at greater distances than most other whales, often tens of kilometers.

According to the Anchorage Daily News, NOAA officials said the proposed rule and the prior listing of belugas could trigger some changes to major development projects over the next decade — seismic drilling for offshore oil and gas, and a dock for the Chuitna coal strip-mine proposed on the west side of Cook Inlet, for example, the agency said.  NOAA said it doesn’t anticipate the stepped-up scrutiny will result in rejection of energy projects in the Inlet. The rule would require other federal agencies to consult with the federal fisheries service before approving projects in the proposed critical habitat areas. Ongoing construction at the Port of Anchorage, planned to continue for several more years, includes monitoring for belugas that may be close enough to be seriously disturbed, though the Port Director said they will be submitting comments on the proposed designation.

UPDATE: Public comments on the critical habitat designation have been extended to March 2010. A NOAA biologist assured locals attending a public meeting that the new designation would not add “onerous” oversight.

Maine towns move toward 1-mile wind farm setbacks

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Two Maine towns grappling with crafting wind farm ordinances are pushing the envelope on setback requirements.  In November,, voters in Dixmont, where plans were afoot to place turbines atop the 1165-foot Mount Harris, approved a 1-mile setback requirement by a large margin.  A story in the Portland Press Herald provides a good overview of the forces behind this vote, and the ripples it is causing in the wind industry.  From the Press Herald story:

Dixmont’s farming heritage is reflected in its forests and open fields, but the town has become a rural bedroom community for Bangor, Newport and Waterville. There are few local businesses; the elementary school is the largest employer. So when developers began measuring wind speeds atop Mount Harris, Hog Hill and Peaked Mountain, some residents saw the chance to lower taxes through revenue collected from renewable energy. Others, however, saw their town with no protection from industrial development. That led to a moratorium on wind projects last November, while the town crafted rules.

What followed was a deliberate process in which the Planning Board studied wind power ordinances in other states and countries, as well as Maine’s model ordinance. The town encouraged residents to make the half-hour drive to Freedom, where they could stand under the whirling blades on Beaver Ridge. Some residents even visited the wind farm at Mars Hill in Aroostook County. Several townspeople spoke to homeowners next to these projects. Among the messages they heard is that the turbines disrupted abutters’ lives. Complaints ranged from noise and visual flicker to health effects that some people blame on living near wind farms. These anecdotes seemed to have a decisive impact, said First Selectman Judy Dann. “I think people listened to the stories that these people had to tell,” she said, and helped convince a majority that wind turbines weren’t a good fit for Dixmont.

Meanwhile, the selectmen in Jackson unveiled a 56-page draft ordinance that includes several unusually far-reaching elements. Setbacks are proposed to be 13 times turbine height, which would come to just under a mile for 400-foot turbines; current industry norms are closer to 300 feet, which would create setbacks of about three-quarters of a mile (likely to avoid nearly all noise complaints, based on recent reports of problems at other wind farms, and several larger research studies of annoyance and sleep disruption around wind farms).  This would require energy companies to negotiate with all families in that large zone if they wanted to obtain waivers, which would also be allowed. The Jackson ordinance will be put to a local vote after the selectmen consider it more fully.

Meanwhile, the Friends of Lincoln Lakes filed a legal brief supporting their appeal of the August decision of the Board of Environmental Protection (BEP). At that time, the BEP affirmed the April 2009 Order of the Department of Environmental Protection, granting a license to First Wind for the construction of the Rollins Ridge Industrial Wind Farm in Lincoln and surrounding towns. The brief questions the adequacy of the noise standards as well as the modeling used to assure compliance with the noise standards. Download full brief here.

Excellent 3-part series on wind turbine noise in Ontario

Health, Human impacts, News, Wind turbines 1 Comment »

In Dufferin County, Ontario, the Orangeville Banner recently ran a very well-written and balanced three-part series on that region’s ongoing controversies over noise from wind farms.  The piece makes very clear both the extent of noise-related disruption felt by some residents (including the first official acknowledgement I’ve seen that the wind farm developer did indeed buy out at least two nearby neighbors who could not adapt to the turbines’ presence), and the larger context that is also a consistent feature of the issue: that the majority of neighbors are not having any particular troubles with the turbines and their noise. The 133-turbine Melancthon EcoPower Centre has spurred recurring noise problems for 17 households, out of 300 that the company calls “neighbors.”  It is not clear whether those bothered are concentrated closer to turbines, or how far from the wind farm households are being included in the 300 number.

Helen Fraser and her husband, Bruce, sold their long time home to Canadian Hydro Developers in 2007, after the couple started experiencing symptoms they attribute to nearby wind turbines. (click for full story)

Helen Fraser and her husband, Bruce, sold their long time home to Canadian Hydro Developers in 2007 (click for full story)

The first of the three articles focuses on several people who have experienced noise problems, including sleep disruption and resultant stress.  While the scientific literature does not show clear cause-and-effect, in which increasing noise or proximity of wind turbines leads predictably to health issues, the utility and the local mayor both say that the complaints received are convincing. “I think when you look at people and the chronologies they’ve put together Read the rest of this entry »