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Another week, another wind farm noise and health report

Human impacts, News, Science, Wind turbines 6 Comments »

Driven by the rising public clamor about health effects reported by people living near wind farms, officials across the nation and around the world have been called on to assess the veracity of these claims.  This week’s contribution to the rapidly expanding genre of “wind farms and health” literature comes from the Massachusetts Departments of Health and of Environmental Protection.  In contrast to last week’s more comprehensive report from Oregon, the Massachusetts report follows in the pattern of the first two similar literature reviews (one funded by the American and Canadian Wind Energy Associations, and another from the Ontario Ministry of the Environment), in that it focuses solely on direct impacts and previously published research papers.  It also addresses a few of the more recent studies, including those by Pierpont, Nissenbaum, and Rand and Ambrose, generally offering them some affirmations for providing new information worth building on, but finding their results not yet solid enough to base siting policy on.

Except for the sections on these recent papers, there is no place in this report for consideration of actual experiences of people living near wind turbines, despite the presence of a neighborhood full of folks in Falmouth who were no doubt ready and willing to share their stories.  From what I’ve heard from these folks, they would offer cogent, detailed, and level-headed testimony about their experiences.

While I can understand why an expert panel might choose to focus only on published material (to avoid the quagmire of trying to assess the veracity of individuals’ reports), and I give the Massachusetts panel due credit for not artificially limiting itself to papers published in peer-reviewed journals, they dropped a crucial ball in neglecting to even mention the word “indirect” in the course of their 164 page report on health effects, let alone provide any sort of acknowledgement or analysis of the ways that annoyance, anxiety, sleep disruption, and stress could be intermediary pathways that help us to understand some of the reports coming from Massachusetts residents who say their health has been affected by nearby turbines.

While the report’s conclusions

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Leading scientists call for reducing ocean noise

Bioacoustics, News, Ocean, Science, Seismic Surveys, Shipping, Sonar Comments Off on Leading scientists call for reducing ocean noise

NOAA humpback with calf copyTwo of the US’s most widely-respected ocean bioacousticians have called for a concerted research and public policy initiative to reduce ocean noise.  Christopher Clark, senior scientist and director of Cornell’s Bioacoustics Research Program, and Brandon Southall, former director of NOAA’s Ocean Acoustics Program, recently published an opinion piece on CNN that is well worth reading in full.  They stress the emerging scientific awareness that chronic moderate noise from shipping and oil and gas exploration is a more widespread threat to marine life than the rare injuries caused by loud sound sources like sonar.  Here are a couple of teasers:

Today, in much of the Northern Hemisphere, commercial shipping clouds the marine acoustic environment with fog banks of noise, and the near continuous pounding of seismic airguns in search of fossil fuels beneath the seafloor thunder throughout the waters. In the ocean’s very quietest moments, blue whales singing off the Grand Banks of Canada can sometimes be heard more than 1,500 miles away off the coast of Puerto Rico. But on most days, that distance is a mere 50 to 100 miles.

Whales, dolphins and seals use sounds to communicate, navigate, find food and detect predators. The rising level of cumulative noise from energy exploration, offshore development and commercial shipping is a constant disruption on their social networks. For life in today’s ocean, the basic activities that we depend on for our lives on land are being eroded by the increasing amount of human noise beneath the waves.

These stark realities are worrying. But emerging technologies for quantifying and visualizing the effects of noise pollution can help drive a paradigm shift in how we perceive, monitor, manage and mitigate human sounds in the ocean. Ocean noise is a global problem, but the U.S. should step up and lead the way.

Clark and Southall make three specific recommendations: to establish a more comprehensive network of acoustic monitoring stations in order to better understand our overall acoustic footprint in the seas; to encourage and accelerate development of noise-reduction technologies (especially to make ships quieter, and also to develop new technologies for oil and gas exploration and underwater construction that generate less noise); and a shift in federal regulations from avoiding acute injury, toward protecting ocean acoustic habitats and ecosystems.

Ocean listening stations go online; US Navy aims to filter out its activities

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A growing network of ocean observatories are adding hydrophones to their arrays of instruments, opening ears into the undersea world.  The data has been shared widely among scientists for the past few years, and a website, Listening to the Deep Ocean Environment, is now compiling the real-time acoustic streams from 15 of the observatories, allowing anyone to listen in; another 11 observatories will be added in the coming months.  This excites scientists and citizens alike. (Though truth to tell, most of the audio streams aren’t all that interesting to listen to most of the time!)

The US Navy isn’t quite so pleased, however. According to a recent BBC article, US Navy oceanographers have arranged to filter data from one of the largest ocean observatories, NEPTUNE, off the coast of British Columbia.  Citing concerns that the recordings will disclose areas of Navy operations, real-time recordings are cleansed of Navy ship (and presumably sonar) sounds, then returned to NEPTUNE operators for uploading to the web. 

Cornell University’s Chris Clark doubts that the Navy’s approach will catch on at other observatories around the world.  According to a piece on The World, from PRI and the BBC, (sounds above from there; roll over tiny screens to ID the sounds), Clark says the US Navy doesn’t own the ocean acoustic environment and has to accept that what was once military technology is now in the hands of civilians.  “The cat’s out of the bag, the horses are out of the barn, whatever the metaphor is, it’s happening,” he says.  The piece notes that this is similar to what happened with satellite imagery. For decades, it too was sensitive military data, but now anyone can go on Google Earth and look down from space.

Oregon “Health Impact Assessment” addresses key indirect wind farm noise impacts

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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.

On quiet Maine lake, new wind farm over a mile away spurs noise issues

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.

RecordHillWindFarm Roxbury ME

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).

Wisconsin towns say: wind farms not so bad, but no more!

Human impacts, News, Wind turbines 1 Comment »

A fascinating article appeared in Midwest Energy News just before the holidays, looking at the current feelings in Kewaunee County, home Wisconsin’s first two large-scale wind farms, which started operations in 1999 and 2000.  Twelve years later, some residents who had raised concerns seem to have come to feel the impacts are less than they feared; if Andrew Nowak, who voted against the proposal when he served on the local zoning board, is any indication, though, their enthusiasm is lukewarm.  Nowak says the sound of his neighbors’ turbines, about a quarter mile away, don’t bother him, but when asked if the wind farm had been a good thing for the community, said simply, “I don’t think they’ve been bad.”

While some locals continue to resent the wind farm’s presence in their community, most seem to have accepted it.  Local appraisers and city clerks say that they haven’t seen any sign of property values dropping in the townships as a whole, and in fact, there are some indications that land values may have risen more than in nearby townships; in addition, at least eight new homes were built within a mile of the wind farm in recent years.  (Note: see the paragraph below, regarding property buy-outs of some neighbors within a quarter mile or so.)

However, at the end of the piece, the “all’s well that ends well” theme is tempered by the fact that “few residents interviewed think the community would favor more wind farms in the area.”  Nowak affirms this, as does Lincoln Assessor and Zoning Administrator Joe Jerabek, who said, “We the people of the Town of Lincoln have made our contribution to renewable energy.”

Indeed, the article, while headlined and framed to suggest that initial fears have been unrealized, mentions that one landowner “and a few others” continued to object about wind farm impacts for years afterward, though offers only one quote from this perspective, a former Town Board member who hasn’t changed his view since voting against the plan.

One local, dairy farmer Joe Yunk, who moved away from the area after struggling with the noise only to find his new land targeted for a wind development, submitted a formal comment to the Wisconsin PSC in July 2010, in which he notes that Wisconsin Public Service, the developer of one of the two early wind farms, bought out two neighbors within a year (after noise issues cropped up) and demolished the homes, while several of his neighbors received below-market buy-out offers. After suing the company to purchase his property (two turbines within a half mile, the closest 1300 feet from his home), they settled with him for slightly under the market value, and his home was put on the market by the developer for 30% below its appraised value.

It appears that in this region of Wisconsin, the community impacts and attitudes pretty much reflect what we’ve seen elsewhere: in the community as a whole, the wind farm is generally accepted (though not exactly celebrated) and overall property values show no dramatic decline, while for a subset of the community the wind farm continues to be seen as an unwelcome presence, and some of the nearest neighbors find their lives severely disrupted.  Once again, it appears that larger setbacks, to prevent these life-changing impacts on the few, combined with easements to allow closer siting to willing neighbors, could have avoided the enduring “bitterness” that Nowak mentions at the article’s conclusion.

Belugas continue to struggle in face of Cook Inlet development

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NOAA Fisheries has released its latest annual estimate of the beluga population in Alaska’s Cook Inlet, and the numbers are sobering.  Their 2011 estimate, 286 animals, is the second-lowest found in the 18 years of surveys, and is 20% lower than last year’s count.  However, NOAA officials stress that year-to-year counts are approximate, with differences in observing conditions and beluga distributions accounting for an error range of plus or minus as many as a hundred animals; long-range trends are more reliable indicators.  Officials say they did not see a large enough number of dead whales this year to suggest that there was indeed a 20% decline.

“Only three dead belugas were reported this year, which indicates that large numbers of mortalities did not occur in 2011,” said Alaska Fisheries Science Center Director Doug DeMaster (over the past ten years, an average of 10 whales a year have been found dead). “While NOAA remains concerned that this population is not showing signs of recovery, at this time we do not believe this estimate represents a marked decrease in the population.”  Indeed, twice before, the counts showed even larger declines, with later years suggesting that actual numbers were not so dire; the previous low count, 278, occurred one year after a count of 366, and two years later, counts were back up to 375. However, since then, counts have been at least 10% lower than that high.  This is especially worrisome, in that this genetically-distinct population of belugas has been listed as endangered, and NOAA designated much of Cook Inlet as critical habitat. (Many other beluga populations remain in other areas, including the western and northern coasts of Alaska, and northern and northeast Canada).

On the longer term, NOAA notes that there appears to be a continuing gradual decline in Cook Inlet beluga numbers, estimated at about 1% per year.  This population of belugas experienced a population crash in the 1980’s (from 1300 down to around 300) 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.

Cook Inlet is a large waterway, leading from the southern Alaska coast inland to Anchorage and Wasilla; a major port expansion is underway, as well as oil and gas exploration and development.  For more on the backstory here, see these previous AEInews post from 2008-2011.

 

Neighbors ask for night time shut down of new WV wind farm

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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.

Onshore wind farm raises ocean noise concerns in Chile

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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.

Wisconsin town officials reassured by visit to wind farm

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Turbine and decibel meterSM copy

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.

 

 

Maine couple push quality of life argument in wind farm appeal

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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.

Australia continues to chart cautious course on wind farms

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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.

Riga, Rumford adopt 40dB wind turbine night noise standards

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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 »

A typical week in wind farm noise

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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:

PalmyraSupervisorsMeetingWEB

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.

NorthDevonFullabrookWindFarmWEB

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.

Illinois forum addresses wind farm health issues, gag orders

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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.)

Wind farm noise, health issues continue to grow—and get jumbled—in Ontario

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AEI Commentary

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 »

David Dunn, the tree whisperer? (great bark beetle story, though!)

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David Dunn is a longtime friend and colleague to AEI here in Santa Fe, and in fact his underwater insect recordings were my first taste of the sounds of the natural world having the potential to be deeply strange and amazing, rather than “just” beautiful. So when he discovered that the bark beetles chewing their way through the piñon pines in the hills of New Mexico were making all sorts of bizarre sounds, and suggested publishing a CD to benefit AEI, I was all for it.

Since then, the bark beetle inquiry has taken on a life of its own, becoming a perfect expression of David’s longtime conviction that artists can contribute in significant ways to science.  The acoustic behavior and communication of bark beetles was previously unstudied by entomologists, and now he’s being called to consult with scientists studying not only the piñon pine beetle, but also the mountain pine beetles ravaging larger higher-elevation and higher-latitude pines, as well as insect pests of the non-beetle persuasion.

This past week, a long article appeared in several Canadian newspapers, providing the most detailed look yet at David’s beetle odyssey.  It’s an excerpt from a new book by Andrew Nikiforuk, Empire of the Beetle: How Human Folly and a Tiny Bug Are Killing North America’s Great Forests.  The article dubs David “the tree whisperer,” though so far he hasn’t quite figured out how to calm the outbreaks; in fact, the research so far seems to be leading more toward driving beetles crazy than calming them.  But after forgiving the headline writer, we can sink into he article itself, which is the most detailed, entertaining version yet of David’s beetle adventures.

Ontario wind farm resistance hits court, election

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Ontario is definitely at the heart of current controversies over wind farm siting.  While an environmental tribunal ruled against a health-based appeal in July, allowing the 8-turbine Kent Breeze Wind Farm to continue operating, many of the same issues will soon be argued in court.  A local family that lives just over 1.1km (just under three quarters of a mile) from the nearest Kent Breeze turbine has filed suit against three companies behind the project, saying that since the wind farm went operational in May, they’ve suffered from vertigo, nausea, and sleep disruption, and more to the point, that the developers knew this could happen.

“Within two weeks of them starting up I was in the emergency. I was dizzy and unable to stand. I was given medication and it has been four months and it hasn’t gotten better. I get motion sickness and light headed,” said Lisa Michaud. “At night I’m afraid to lie down because of the constant vibration and spinning.”

At the heart of the court case is the claim that the possibility of health impacts is known to exist, and indeed, parts of the report from the tribunal appeal which lost last month are called on to affirm this:

“This case has successfully shown that the debate should not be simplified to one about whether wind turbines can cause harm to humans,” the Environmental Review Tribunal stated in a report on the Kent Breeze project. “The evidence presented to the tribunal demonstrates they can, if facilities are placed too close to residents.”

In essence the Tribunal ruled that existing Provincial siting rules are sufficient to meet the threshold it imposed; these rules call for at least a 550m setback from homes, about half of what the family filing suit is living with. As reported in detail on AEInews at the time, the Tribunal report is a fascinating overview of the current state of the wind farm noise issue, with long summaries of expert testimony from both sides. The tribunal, while affirming the value of ongoing research into health effects and the nature of wind farm noise, ruled that the more cautionary evidence remained “exploratory,” rather than “conclusive,” and set a threshold for ruling that would require that the wind farm “will” cause “serious harm.”  Short of that, the Tribunal ruled that it could proceed. It seems likely that the court will be asked to review much of the same conflicting testimony; I am not sure whether the legal thresholds are different there than in the Tribunal process.

Meanwhile, the wind boom in Ontario has become a key issue in the current provincial election campaign, with both the candidates taking opposite stands and citizens speaking against current siting standards province-wide. Since the current Liberal government sponsored the Green Energy Act and its current standards, much of the opposition takes a decidedly conservative edge, often including opposition to government support for renewable energy in general and wind energy in particular. It certainly goes far beyond noise concerns for many of the most vocal opponents, with health impacts joining more generally conservative principles in arguments being made. One woman who has had to move from her home recently told a rally that the Liberal government is “denying” the health impacts of turbines and “ignoring” the people who are suffering. “People just aren’t going to sit back and take it anymore…We’re going to have your government so low, so low, so low, you’re not going to get elected. It’s as simple as that.”

Meanwhile, Liberal candidates including current leader Dalton McGuinty note that the standards are among the world’s most precautionary, and refer to a 2010 provincial report that focused on direct health impacts: “I rely on our chief medical officer of health here in Ontario to tell us what’s safe for our families,” McGuinty said Thursday. “What we have heard, of course, is doctors [and] nurses for 20 years now, they’re saying you got to shut down coal-fired generation in Ontario.”

Victoria 2km wind farm buffer takes effect

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The State of Victoria (Australia) has enacted new wind farm siting guidelines that prohibit construction within 2km (1.25 miles) of a home unless the owner has signed off on the nearby turbine(s). In addition, the new guidelines prohibit wind farms within 5km of many existing villages, in order to allow for future growth.  And, several areas with “a high degree of amenity, environmental value, or are a significant tourist destination” are excluded from development. (In Australia and New Zealand, the term “amenity” is often a factor in planning decisions; it largely corresponds to what we might also term rural quality of life.)

The new guidelines set a 40dB noise limit, reduced to 35dB in areas of “high amenity.”  It may be of interest to note that the Victoria planning authorities seem to equate 35dB to about a 2km setback, whereas an Oregon noise standard of 36dB has more often led to roughly half-mile, or 1km, setbacks.  It appears that the noise modeling is using different parameters in Oregon than in Victoria.  It’s also possible that the 2km buffer is designed to protect “visual amenity,” with the noise limit being a secondary feature of the guidelines.

Already, some wind farm developers have cancelled plans to build in Victoria, while locals who have experienced quality of life or health impacts praise the moves. I was especially struck by the reports of Adrian and Helen Lyons, who have 15 turbines within about 3km of their home, with the closest about 1.7km (just over a mile) away; both have reported a feeling of sustained pressure in their ears when the wind comes from the north.  The ear pressure has disturbed their sleep.  This spurs my ongoing question as to whether some of the physical sensations may have more to do with air pressure downwind of turbines, rather than noise levels.  To my knowledge, factors creating pressure differentials have not been investigated, although the related investigation of turbulence effects is on the research agenda of agencies and companies seeking to optimize turbine layout in wind farms.

See this site to download the new Victoria wind planning guidelines.  Or, see this Advisory Note summarizing the new amendments, and this PDF of the full planning and policy guidelines.

Wind turbine manufacturers aim to reduce noise

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Two recent articles in trade magazines caught me up on efforts taking place within the wind power industry to reduce the noise levels of wind turbines. While it’s great to know it’s on everyone’s mind, it also appears that so far, noise reductions are modest.

In the July 2011 issue of North American Windpower (back issues not available for online reading, sorry to say), one of the feature articles was “Turbine Manufacturers Focus on Reducing Noise Emissions.”  It included discussions with reps from most of the major turbine manufacturers, and was full of fascinating hints of ongoing research.  As the article noted:

As the so-called “low-hanging fruit” of land with good wind and transmission access gets used up and wind turbines move closer to residential areas, noise concerns are expected to become more prevalent, according to wind turbine manufacturers.

“It’s on the top of the minds for all manufacturers,” said Paul Thompson, commercial director of Mitsubishi’s wind turbine group, “we’re all doing things to reduce the amount of noise that’s generated.”  GE’s Henrik Stiesdel stressed that wind turbines do “have a noise impact.  The main remedy is to ensure that they are not sited to close to dwellings. If that’s not possible because you are in a densely populated area, then we have remedies where we control the power output when conditions are such that noise might be exceeding limits.” The article describes this system:

GE’s sound power management (SPM) works by optimizing control setting based on real-time wind conditions, according to Sean Fitzgerald. The SPM option can be configured for day and night modes, at angular intervals depending on the mode switching and based on wind turbine placement. “These applications enable the customer to specify the appropriate, desired sound emission characteristics by customizing the sound power curve to the precise requirements over the entire wind speed range,” Fitzgerald tells NAW.

Gamesa’s Miguel Angel Gonzalez-Posada notes that there’s a trend of having to keep noise as low as possible near populated areas, especially at night.

Read the rest of this entry »

Roanoke County decides 60dB, 1000ft is good for wind farms

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The Roanoke County Board of Supervisors has adopted a wind energy policy that sits on the least-protective edges of current siting standards: a 60dB sound limit, and setbacks of 1000 feet from homes. Four of the five supervisors supported the proposal, saying it would protect residents; the 60dB limit was said to be comparable to sound along US 460, a four-lane federal highway in the area.

A fifth board member, representing the district where the only current wind farm proposal is sited, encouraged the board to hold off on setting absolute limits; Ed Elswick said the county should wait until it has a proposal and hire experts to weigh in “rather than grabbing numbers out of the air.” That didn’t stop him from tossing a number in the hat: he proposed that sound be limited to levels typical of rural areas, suggesting 30dB at the nearest property line.

UPDATE, 10/12/11: Elswick has asked the board to reconsider the 60dB limit; it will be on the agenda at a meeting in late October. Two board members said they knew they wouldn’t change their votes; one said he wanted to hear further discussion, and the fifth board member was not present when Elswick raised the issue again. And, 26 local residents have sued the Board of Supervisors, saying that the sudden shift from a 2600-foot setback proposal to the 1000-foot decision lacked proper notice of a public hearing, and was “clearly unreasonable, arbitrary or capricious.” UPDATE, 10/26/11: The Board of Supervisors voted to not reconsider their previous decision.

Roanoke

The area where 15-18 turbines are currently proposed is a section of hills about ten miles from Roanoke, a near-to-town rural enclave that has federal highways two to four miles in two directions, along with I-81 a few miles distant (see 2 mile scale at lower left, above). It appears that no existing ambient levels have been determined there, though it would not be surprising if some of the highways are faintly audible at the site.  There may well be homes in valleys, however, where current soundscape conditions are notably free of road noise, and which will now face next-to-the-highway noise levels from turbines on ridges nearby.

It is unclear at this point how many homes are close to the 1000-foot setback distance; these will be the places where the soundscape is likely to be most dramatically changed. A half-mile setback was proposed in a previous draft of the policy; this would have likely minimized the likelihood of major impacts on neighbors, though it may not have eliminated noise issues entirely. In areas such as this, it’s often hard to site wind farms without fairly relaxed noise and setback limits.  Here, as in many other towns and counties, board members apparently felt that it was more important to not exclude wind development than it was to maintain current soundscape conditions in this rural enclave.

NY windfarm latest to trigger noise issues – it’s easy to see why

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A sprawling wind farm in northern New York state is the latest new installation to trigger push-back from neighbors complaining about excessive noise.  The Hardscrabble Wind Project is centered in Fairfield, just north of I-90 between Syracuse and Albany; its three-dozen turbines stretch across parts of three towns, covering an area of roughly ten miles by three miles.

Hardscrabble herkimer fairfield NY

A recent local press report summarizes the current situation: several nearby residents have complained of noise issues, leading the developer, Iberdrola, and the town of Fairfield to commission noise studies to determine what sound levels were occurring.  The Iberdrola study found that sound was generally in line with the predictions made during project planning, falling below the regulatory limit of 50dB, though in high winds some recordings came in above that with combined turbine and ambient wind noise.  The town study will take place this winter, when the leaves are off the trees.

UPDATE, 10/4/11: Good local article on the preparations for the new noise study, with a classic example of neighbors reacting differently to the sound, one saying the noise “is really bad, very hard to live with,” and another saying “to be honest with you, I don’t even notice them.”

A look at the sound assessment documents compiled as the project was being approved offers some hints as to why this project might trigger noise complaints; several factors compound the likelihood of issues here.  First is the town’s noise limit of 50dB for non-participating neighbors, which is on the very high end of regulatory limits for wind farms.  The sound assessment went through several versions as the project was revised and refined; a noise analysis from March 2009 lists 25 homes where the modeled noise levels were predicted to be between 45 and 50dB; 11 were hosting turbines and 14 were not. An apparently final revised noise analysis dated December 2009 (after some site adjustments to some turbines) does not list the affected homes, but includes very detailed sound contour maps, which show well over a hundred homes sitting in the 40-50dB zone, where it can be expected that a significant minority of residents will find the noise intrusive (based on experience at other wind farms in similar communities, and on the limited research data we have available; for more on this, see AEI’s 2010 NEWEEP presentation on community responses).  It all adds up to the classic conditions that have often led to problems in rural towns that are home to many residents who are not actively farming and ranching: too many homes receiving noise levels close to (relatively high) regulatory limits.

The final hint that there might be problems lies in the March noise assessments definition of existing ambient noise. This is often the key factor that is given too little attention in wind farm siting,

Read the rest of this entry »

In-depth soundscape ecology study underway at Alaskan wildlife refuge

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A really fascinating multi-year study is underway at the Kenai National Wildlife Refuge which sits on a peninsula along the south side of the Cook Inlet in Alaska (Anchorage and Wasilla are at the innermost tip of Cook Inlet).  Tim Mullet, a Ph.D. student at what looks like an amazing program at the Institute of Arctic Biology, is undertaking what may well be the most comprehensive soundscape analysis ever undertaken on a landscape scale. “As far as I know, nobody has attempted to model sound in the landscape,” says Mullet. “We could encounter some big surprises there.”

Over several summers and winters, he is collecting recordings with 13 units placed in different areas of the refuge; some are permanent locations, and others he moves around in order to explore the soundscape in more areas. He already has 85,000 hours of sound data, and hopes to expand his recorder array to 23 units this year as well. These two articles provide a great overview of what Tim’s up to.

Snowmobile density in the Kenai NWR (red most, blue least); note that the shaded areas on the east side are nominally closed to snowmobile traffic, yet show some sign of activity.

Snowmobile density in the Kenai NWR (red most, blue least); note that the shaded areas on the east side are nominally closed to snowmobile traffic, yet show some sign of activity.

“At this point, I’ve got an idea that 30 to 40 percent of Kenai’s wilderness could be affected by human–made noise,” says Mullet. The study goes beyond simple decibels (loudness), though. It is a foray into the emergent field of soundscape ecology, which examines the interplay of anthrophony (human–induced sounds) and biophony (natural sounds).

Loudness is “a piece of this study,” says Morton, “but another piece is the origin of sound—whether it’s human or nature—and developing a ratio between the two. It’s definitely cutting edge.” Understanding the relationship between anthrophony and biophony is important to the refuge and wildlife conservation in general, Morton says, because “human–generated noise can drown out natural noises—and that can be a huge deal, to the point where animals can’t actually hear themselves.”

In addition to collecting and mapping sounds, Mullet is studying whether moose who live closer to high levels of sound show higher stress levels than those in more sonically pristine areas.  While some snowmobiling advocates seem concerned that Mullet’s work may lead to new restrictions on their access to the refuge, Mullet himself understands and appreciates the key role of snowmobiles in Alaskan recreation, and aims to simply clarify what the various cumulative impacts of noise may be. Snowmobile trails create other impacts as well, especially compacting snow, which can benefit wildlife by offering travel paths, though biologists are also interested in how this easier travel may shift some predator/prey relationships.

More info: See two articles written by Mullet, one on the many qualities of snow, and the other exploring our different ways of listening, and introducing the Kenai study.  Also of interest from Tim is this research proposal, which summarizes previous research into both the impacts of noise and other snowmobile impacts (unfortunately, the sections of the proposal that are yellow-highlighted come through on the pdf as blocked out).

Magical more efficient wind turbine of the month

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Wind 200

A Japanese research effort that’s been around for a while has gotten a blast of media fame this week, claiming the potential to triple power generation by using a ring around the blade-swept disc that focuses wind past the blades, as well as, I think, capturing some of the energy off the blade tips.  Sounds great in a headline, but as with most new turbine design “breakthroughs,” this one is early in R&D: the field trial models are only 5kw, with two 100kw, 13m-diameter, models recently erected. Whether the design can scale up, or be constructed economically in large arrays of smaller units, remains to be seen.  The weight of the ring has to be a challenging design feature when it comes to actually building large versions of this in the real world. Nearly every efficiency-improvement approach also touts a reduction in noise output as one of the benefits.

The best coverage of the “Wind Lens” research appeared on Clean Technica; they included these links to the lab’s research page and a conference poster. For good measure, here’s a couple other new approaches to increasing turbine efficiency previously covered in Clean Technica, with equally uncertain futures.  More power to all these researchers, whether in university labs or backyards.  Just don’t assume that a catchy headline means the revolution is neigh.  (Being a dreamer, I remain quite fond of ongoing research in California that seeks to harness extra energy by mimicking fish schooling patterns with small vertical-axis turbines, as covered previously here.)

British House of Lords debates 2km wind farm setback bill

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Apparently this proposal has little chance of proceeding, but in June the British House of Lords spent two hours discussing a bill that would establish a 2km setback provision for new wind farms.  Such a setback would leave little room for new wind farms in England, but many suitable sites would remain in Scotland.

The Parliament website has the full text of the debate, replete with the always-entertaining combination of formality and shouted “interventions” from dissenting members.  Go to this page and scroll down just a bit, past the prayer and a quick “dog control notice”; the first major topic is the wind farm bill, and discussion lasts from 10:17 until shortly after noon.