Natural England, a recently-established “statutory consultee” charged with advising the UK government on projects that may affect wildlife or the English countryside experience, has published a document that outlines its approach to providing guidance on wind farm siting.  The guidance considers both established parks and other unprotected wild lands and geo-diversity sites, as well as areas of deep peat, and areas of hightened bird sensitivity.  It also mentions previously-mapped areas of the greatest tranquility, though it is not clear just how much weight each of these various designations will carry as it balances the many factors that go into its recommendations.

Read more about the guidance on this post at New Energy Focus, or read Natural England’s press release here.  You can download the guidance document from this web page.

A key research paper from National Park Service and Colorado State scientists has been published in Trends in Ecology and Evolution.  The paper, which got a lot of press when it was first made available online in the fall, introduces two key new metrics for measuring the effects of noise on animals.  The first, “alerting distance,” is the distance at which sounds can be heard: these may be sounds made by a species to alert others to danger, or sounds made by predators (which prey animals want to hear, so as to take cover).  The second, is “listening area,” the full area around an animal in which it can hear other animals’ calls, footsteps, and wingbeats.  A key insight offered by this approach is that even moderate increases in background noise (from nearby roads, airplanes, or wind farms) can drastically reduce an animal’s listening area.  The paper, which was free while in pre-press, is now available only to subscribers to the journal or other academic journal services; an article published in Park Science magazine and free to view online introduces much of the same material (be sure to click on the links to the figures, as they illustrate the concepts very well): see the article here, and check out the entire special soundscapes issue of Park Science here.

A very good article in the Aspen Times introduces the research, and includes many extremely insightful quotes from the researchers.  Go read the whole article! Three bits that are especially worth keeping mind are:

• “The male sage grouse, in its mating displays, produces high-frequency popping sounds and swishing sounds,” Fristrup said. “It also uses a low-pitch hooting sound, which carries the farthest from the display area as a long-distance advertisement. The danger is, it doesn’t take a lot of noise to substantially reduce the range at which females or other males could hear that low-frequency hoot. So the attraction radius of the display ground could contract substantially with the inability to hear a hoot.” The authors note that some species can reduce the effects of masking by shifting their vocalizations. This is especially true when members of a species are communicating with each other. However, when the sounds a species depends on emanate from another species (such as a mouse burrowing under the snow, which an owl needs to hear as it hunts), there is less room for compensation.
• Carnivores like lynx, who sit at the top of the food chain, can be particularly sensitive to habitat degradation of any type — including auditory — since each individual requires a huge hunting territory. “If one part of the range of a top-level predator is compromised, it may not take much to squeeze it out,” Fristrup said.
• Contrary to what one might expect, noise is not always more disruptive when it’s louder. Snowmobiles or cars, for example, might be less disruptive to elk or deer than a hiker or cross county skier would be. “There’s pretty good evidence that so-called quiet use can disturb wildlife. If it’s a noisy source, the animal perceives it a long way off and can track its progress. There are no surprises, and it can go on feeding or doing whatever else. A quiet sound, like a snowshoer’s footstep, is only perceptible when it is very close, potentially startling the animal,” Fristrup said.

To read AEI’s detailed lay summary of the research paper, published here in December, see this link.

A radical new approach to offshore wind turbines is being developed by UK researchers could solve one of the major challenges of offshore wind development.  The Novel Offshore Vertical Axis (NOVA) Demonstrator puts the moving parts at the bottom of the unit, greatly simplifying maintenance. (How they will deal with corrosive factors will be interesting to see!)  The units are 100m tall, and are planned to generate 5-10MW; however, they are some years away, with the initial test model planned for deployment in 2015.

Aerogenerator NOVA concept

For more on this new design, see this article in the Guardian and the NOVA website.

Here’s a bit of news that might be spun either way, depending on your predilection.  Jane Davis, who was driven from her home by wind farm noise, has been compiling information on English wind farms and noise complaints; she has found that 37 wind farms have spurred some sort of noise complaints nationwide.  This amounts to about 1 in 7 UK wind farms, in contrast to an oft-repeated mantra that “only four” UK wind farms had noise issues, and they’d been “resolved.”  The new numbers could support those cautioning that wind farm noise issues are more widespread than generally acknowledged, AND those who claim that noise issues are the exception rather than the rule; it certainly reinforces AEI’s theme that we need to acknowledge that a minority of people are affected by noise around wind farms, and that we must come to grips with how to address this.

This article in the Telegraph details some of the information shared at a gathering of wind farm noise campaigners, WindCon2010.  Gillian Haythornthwaite, who lives near the wind farm in Askam with her partner Barry Moon, said it has been a “devastating” experience. ”It is a dreadfully irritating whoosh, whoosh noise,” she said. “It is unbearable to be outside in the garden when there is the noise.”

Read the rest of this entry »

This one slipped past me when it happened last June, but it’s well worth noting now.  Complicating assessments of the risks of bird deaths at wind farms is the fact that two-thirds of migrating bird species migrate mainly at night; Cornell’s Bioacoustics Research Program, which has already done groundbreaking work in elephant communication and underwater listening systems, has proposed that combining their autonomous recording devices with radar data could provide the missing information on exactly when and where concentrations of migrating birds may exist near proposed wind farms.

A compelling animation highlights the large-scale patterns: The color-coded radar map illustrates areas of precipitation over the coasts as well as vast movements of tens of millions of birds, bats and insects across the entire country. In the densest areas, the color-scales indicate movement of 2,000 birds per cubic kilometer. ”You’re talking about a massive movement of birds overnight,” said post-doctoral fellow Andrew Farnsworth.

Radar imagery of night-migrating birds, bats, and insects

Although radar data can show the magnitude, location, timing, speed and direction of migration patterns and provide information on key stopover sites, they do not identify types of birds or accurate flight altitudes, Farnsworth said. But combining radar data with data from flight call recordings and tracking tags on birds could allow researchers to identify many species in key areas. Bioacoustics program director Chris Clark added that recorders are cost effective, can be automated for many months at remote sites, provide data on many species simultaneously, increase the probability of tracking secretive and endangered species, and could allow regulatory agencies to develop computer models to assess risks to birds from wind turbines. He acknowledged, however, that using such acoustic technology could produce a massive “data crunch”; a single microphone over a three-to-four-month period can record 120 to 140 gigabytes of data, so data from several hundred microphones would be too much to process without advanced software. Also, researchers would need to better recognize the wide variety of flight calls and learn to integrate data from radar with those from acoustics and tracking tags, he added. More research is needed, Clark stressed, to determine at what altitudes species tend to fly and whether birds sense turbine blades and avoid them.  Read full account of the presentation in the Cornell Chronicle, with link to the radar map animation.

Electrical engineer Siva Sivoththaman has been named to the newly-created Ontario provincial Research Chair in Renewable Energy Technologies and Health.  Local activist groups that have raised concerns about the effects of wind farm noise on neighbors had hoped that this position, created as part of Ontario’s new Green Energy Act, would take the lead in formally investigating the negative health effects some neighbors of wind farms have reported.  However, the choice appears to be more oriented toward the technology aspect of the Chair’s responsibilities.  As noted in the request for proposals: “The Chair in Renewable Energy Technologies and Health will focus first on emerging science and technology related to wind turbines, and then will explore the potential health effects from renewable energy.”

According to a news release, “Dr. Sivoththaman will bring focus to multi-disciplinary activities in renewable energy technologies and health, ensuring that health and safety are top priorities in the induction of new technologies. His research program will develop new technical approaches and will provide guidelines in setting standards to ensure health and safety in the manufacturing, use, and end-of-life phases of renewable energy technologies.” Sivoththaman’s research centres on silicon-based crystalline and thin-film photovoltaic devices, and he serves as director of the Centre for Photovoltaic Systems and Devices, which occupies much of the photovoltaic research building beside Matthews Hall. His interest extends to nanocrystalline semiconductors, and he was the first director of the University of Waterloo’s nanotechnology engineering program when it was launched in 2004.

Two leading Ontario wind activist groups expressed their disappointment with the choice; Wind Concerns Ontario said “We have no faith in any meaningful body of evidence being produced on health effects from wind turbines by this government-funded non expert and Ontarians will suffer for it,” while the Society for Wind Vigilance chair Dr. Robert McMurtry said the choice missed the mark in that “the lead and expertise of this Research Chair would more appropriately have been a clinician scientist. We strongly encourage the new Chair to seek the appropriate collaborators as the research program is established.”

It is as yet unclear what the Chair’s timeline will be in addressing the dual (and quite distinct) topics he is charged with overseeing.  Given the widespread concern about health effects, and the role this concern is playing in the wind development process in Ontario and elsewhere, we hope that the two topics will be pursued simultaneously.  And indeed, as McMurtry suggests, it is clear that the Chair will need to bring in some experts in health and acoustics to effectively address the health aspects; in the spirit of collaboration and inclusiveness, we can also hope that his research/investigative team draws from qualified experts who have expressed concerns about wind noise, as well as those who have previously worked on reports that found few health effects.

The most recent issue of the Marine Ecosystem and Management newsletter (download here) has several features that offer a good sense of current efforts to adopt Marine Spatial Planning (MSP) and its related management principle, Ecosystem Based Management (ESB).  The lead article centers on reports from Massachusetts, Norway, and Germany, each oriented toward the relationship between MSP and ESB.  Shorter pieces include interrviews on related topics and direct readers to recent management plans, proposals, and reports by the US Federal Government, the State of Massachusetts, and Papahanaumokuakea Marine National Monument in Hawaii.  For more on MEAM programs and publications, see the MEAM website.

The Fox Islands Electrical Cooperative on Vinalhaven, an island off the coast of Maine, has begun a month-long experiment as a first step in trying to come up with a local solution to noise issues from three wind turbines that began operating in November.  About two dozen people within a half-mile of the turbines have reported annoying levels of noise, with six property owners claiming that their lives are severely impacted.  Others in the same area who can hear the turbines are not particularly bothered by the noise.

Shortly after the turbines started operating, and some residents (including some who were excited about the wind farm, and some who had been skeptical) reported unexpected noise issues, neighbors began noting the times that the sound was most troublesome, in an effort to identify what wind directions or atmospheric conditions might be most to blame.  At its January meeting the Board of the electric coop decided to conduct a month-long “experiment” during February, in which the turbines would be slowed down in random patterns.  Sound measurements will be made throughout the month, and the 38 households within a half-mile are being asked to log their sense of the noise on a regular basis (half these households are summer people, so are unlikely to be participating). In a letter to coop members, the board said the experiment “will enable us, as a community, to figure out what to do and come to a solution that works, as well as possible, for everyone.”

A very detailed article in The Working Waterfront, a local paper, features a variety of comments from a locals about the process that is underway to find a community-based solution to the noise problems. Some find that the noise is moderate enough to be tolerable, easily drowned out by other sounds such as the TV or a car passing by, or being no more bothersome than a dishwasher running in another room; one person remembers the noisy generator that used to provide power to the town in the 60s and 70s, which people got used to.  Some who have been disturbed share their perceptions, as well;  Ethan Hall notes that “I’ve never heard anything in my life that sounds like it.”  Both he and Lindgren (another neighbor being affected) believe that current sound measurement standards do not take into account the complexity of turbine noise and its true impact. “The nature of the sound is so unique, that to try and quantify or qualify it with a strict dBa [decibel] measurement is an entirely inadequate way of describing the effect on people and surroundings,” Hall feels.  An hour-long radio interview with Hall and others being affected, recorded this past December, is available on the WERU website.

The UK government announced lease bid winners for nine offshore wind development zones that together aim to provide 25% of the country’s electricity by 2020.  The winning companies will next submit development proposals, which will go through normal planning and permitting processes, with construction targeted to begin in 2014.

Prime Minister Gordon Brown said: “Our policies in support of offshore wind energy have already put us ahead of every other country in the world. This new round of licences provides a substantial new platform for investing in UK industrial capacity.”

For more detail, see this post on the Yes2Wind website, which promotes wind development in the UK.

UPDATE (3/9/10):  In the wake of the “Round 3″ leases noted here, doubts have been raised about whether the goal of fully building out the leases is realistic; limits in the supply chain for building such turbines is a major concern, as is financing.  See these two articles for more.

This one is a bit old (from last spring), but seems worth pointing to because it provides a somewhat new perspective on the wind farm noise debate.  US Congressman Eric Massa represents a district which is at the center of public concern about noise issues, thanks to a proposed wind farm in Plattsburg, not far from an existing wind farm in Cohocton that has spurred quite a lot of complaints.

In this interview with a local radio station, the Congressman describes some of the stories he’s heard from constituents, as well as his larger questions about the logic of building wind farms in areas like this that have only marginal wind resources (winds are strong enough to produce electricity only 30% of the time).  He also frames the issue as one of small towns being over-powered by the interests of foreign companies.

Two of the more compelling tidbits come in a brief moment of the interview, when Massa speaks of a constituent who “agreed to have a lease on his property and now he is saying – I have to move out of my property. It’s quite amazing. Not to mention the fact that as we talked about, hunters are now coming up and telling me that there’s no wildlife anywhere within distance, and I’m talking three to four miles, of any of these wind turbines because these wind turbines emit low frequency vibrations that drive the deer away.”

The latest in AEI’s ongoing series of comprehensive special reports on key topics is finally done!

This one is modeled on AEI’s acclaimed annual reviews of science and policy developments in ocean noise, but focuses for the first time on wind farm noise issues.  The 30-page report covers new research, public concerns, and industry trends over the past year.

Read the report in the embedded pdf reader below, or download a pdf copy.  Click on to below the fold for a table of contents and the report’s brief Introduction.

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A hearing by the Minnesota Public Utilities Commission heard testimony from residents and agency staff this week, and indicated that it was going to take its time in setting statewide wind farm siting guidelines.  ”I think there are a lot of remaining unanswered questions. I think there are a lot of … substantive questions as well,” Commissioner Phyllis Reha said. “I think the commission has a lot of work to do before we make any kinds of decisions.”

Monday’s hearing focused on a report issued last year by the Minnesota Department of Health outlining the potential health impacts from wind turbine noise. The PUC and its staff requested health department officials review scientific literature after people statewide raised concerns regarding wind projects.

In the scientific report, state health officials - drawing from National Research Council findings - noted that noise from wind turbines “generally is not a major concern for humans beyond a half-mile or so.”  Nonetheless, the report and PUC staff recommended that setbacks be increased only to 1000 feet; current regulations set a 500 foot minimum, but the night time noise limit of 50dB means that in practice, most turbines are sited at least 700-1200 feet from homes.

Some groups - including Goodhue County residents - have advocated setbacks of six-tenths of a mile or even 1.25 miles to prevent possible health effects, a point PUC staff and others say is supported by “scant” evidence. Still, Commissioner J. Dennis O’Brien said, “We know these issues are strong and heartfelt … and genuine and real. We’ll just have to struggle with it for a while, I think.”

Two different acoustic studies near the Willow Creek Energy Center in eastern Oregon have found that the state’s wind farm noise ordinance is being violated at several homes nearby.  How often and by how much the violations are occurring remains under contention. As reported by the East Oregonian, the commission heard from several acousticians as well as the neighbors themselves.

The state allows wind farms to be up to 36dB at neighboring homes (10dB over the night-time ambient of 26dB–based on the assumption that excess noise will not be bothersome until it exceeds ambient by 10dB).  After several neighbors raised concerns about noise, Invenergy, the wind farm developer, hired acoustical consultant Michael Theriault to take measurements.  He found that noise levels at three homes were “usually less than 37db” and that at one home, “the noise ‘moderately’ exceeded the noise code about ten percent of the time.” (it is unclear what “usually” means in this report, or what averaging period was used in the determination)

However, the Theriault did no recordings when wind speeds exceeded 9m/s, because the company says their turbines don’t get louder after that point.  This may well be true, but sound propagation can vary widely with atmospheric conditions, especially when wind is higher aloft (at turbine hub height) than on the ground.  Acoustical consultants hired by the four landowners presented findings that included measurements when wind speeds were higher, which showed that the noise at the Eaton’s residence hovered just above the noise standard on a regular basis, and at the Williams residence it regularly went above 40 decibels. The wind farm consistently broke the noise rule at precisely the time when Theriault decided not to use the data - when wind speeds exceeded 9 meters per second. When the data is analyzed in a wider range of wind speeds,  the wind farm was in violation of the rule 22 out of 37 nights. ”I’m not sure how someone can say this is an unusual, infrequent event,” said Kerrie Standlee. “To me, 59 percent is not occasional or unusual.” Standlee’s noise study also went beyond Theriault’s in that he gave the residents a sheet of paper to log their experiences with time and date. He then overlaid those comments on the data and showed that when the residents reported high noise, the wind was blowing from a particular direction or at a particular speed.

The commission also heard heartfelt testimony from the residents themselves, who said that their lives had been completely changed since the wind farm came. ”A basic right in my life is to live in my beautiful home with my peace and quiet, and now I can’t do that,” Dan Williams said. When the testimony ended, the planning commission agreed to wait until their next meeting to make a decision about whether - and how - the Willow Creek wind farm must mitigate the noise problem.  An earlier article focusing on the experiences of people near the wind farm is available here.

The Japanese Environment Ministry is gearing up for the April launch of a nationwide field survey around all 1500 wind turbines in operation in the country.  Prompted by health complaints by some neighbors, the survey will the first such comprehensive study of the question; low frequency and audible noise will be recorded, to see whether there is any correlation between these sounds and the reported effects.  According to the ministry plan, the survey will first ascertain whether there have been problems reported in the vicinity of wind turbines. If residents complain of health problems, their symptoms will be examined. Measuring equipment will be placed in their homes to find out the relationship between the turbines and health problems. The distance between the turbines and homes as well as geographical features of the area will also be examined. About 30 of the nation’s 376 wind farms (1-20 turbines each) have prompted formal complaints to date.  For more, see this Japanese news report.

In what could be a precedent-setting move, the Ontario Assessment Review Board (ARB) has slashed the taxable value of a house because of noise from a transformer station across the street.  The transformer, which site 360 meters (about 1200 feet) from Paul Thompson’s home, produces a constant hum of about 40dB in Thompson’s home.  In 2008, the Municipal Property Assessment Corp. assessed the 1,320-square-foot house at $255,000; Thompson felt that assessment may be fair if not for the noise from the recently-installed substation, and appealed.  According to an article in the Home section of the Toronto Star, Thompson introduced evidence at the hearing showing that the transformer station noise was audible within the house with the windows closed. He described the noise as a “nightmare” and a constant nuisance that not only affects his day-to-day activity, but also impacts the sales value and marketability of his property. In reaching its decision to cut his assessment in half, board member Marques wrote, “The Board finds that the constant hum alleged by Mr. Thompson does exist and significantly reduces the current value of the subject property. The best evidence is the audio portion of the CD (Exhibit No. 1) and the testimony of both parties. ”Having heard this nuisance, apparently sanctioned by the Municipality, the Board accepts Mr. Thompson’s testimony that the stigma of noise contamination has a negative impact on the value and marketability of the property, and that after learning of the hum, prospective purchasers will quickly lose interest in purchasing the property. The Board is satisfied that a very substantial reduction is warranted.”

It is especially interesting that the ARB felt that Thompson’s home value was so dramatically affected by sound of 40dB; many municipalities c0nsider this and higher levels to be acceptable.  Wind turbine noise, while varying widely with wind conditions, can be 45dB or higher at similar distances (1000-1500 feet), and remain above 35dB for up to a mile.  As Bob Aaron, a real estate lawyer and author of this article, notes: “Thompson’s successful appeal of his assessment is only the first of many similar cases that are certain to follow. The result, of course, will be a significant reduction in the tax base of municipalities like Amaranth, which play host to wind turbine farms.”  This hearing took place in September 2008, but only recently came to light.  Bob Aaron has posted the ARB decision on his website.

While offshore wind, especially floating deep offshore designs just beginning to be tested, offers great promise for reliable electrical generation out of earshot of communities, there remain several key technical hurdles to overcome.  In addition to needing more ships that can transport and install offshore turbines and vastly expanded transmission lines, a key concern is that wind turbines can interfere with radar signals, raising concerns about national defense implications of widespread offshore wind development.  The Department of Homeland Security and the NOAA are soliciting proposals for new techniques that could be used to accurately assess the extent and degree of radar interference by offshore wind farms.  The proposal affirms that the “intent is not to impede the propagation of wind turbines but to discover a means to co-exist.”