I’ll be one of three presenters at what promises to be an informative 90-minute webinar taking place on Tuesday July 13.  It’s one of a series of wind energy programs being produced by the New England Wind Energy Education Project, a DOE-funded public information effort.  My piece will add a look at the experiential reports of wind farm neighbors, as well as the few studies we have that help clarify how common noise disturbances are around wind farms (hint: it’s much more than many people think, but also less than some believe); I also take a stab at understanding the variable responses of people hearing the same levels of sound/noise.  Joining me on the panel are Mark Bastasch, who will provide a primer on noise measurement and the sources of wind turbine sounds, and Ken Kalinsky, who will focus largely on the various approaches to regulating wind farm noise.  The three 20-minute presentations will be followed by a discussion and question and answer session that will last for roughly a half hour or so.

The webinar will take place on Tuesday July 13, from 2-3:30pm Eastern Daylight Time.  You must pre-register to receive login information.
For more information on this free webinar, see this PDF information sheet.  You can register from there by email; or, just use this email link and request registration information for Webinar #2.

Ontario’s environment ministry has released proposed siting guidelines for offshore wind turbines that set a minimum distance of 5km (3.1 miles) from shore.  The rules, which are now open for public comment, will be subject to public hearings in the fall. Ontario does not have ocean frontage; the rules are meant to govern wind farms planned for the Great Lakes.

The proposed standard would undermine some proposed wind farms, which are aiming to be 2-4km from shore.  It is likely that the proposal would greatly minimize the visual impact of turbines, and would may also reduce sound impacts to an acceptable level.  As noted in this brief essay, sound travels very easily over water, so that typical onshore setbacks could be insufficient for offshore sites.  Some reports from near the Wolfe Island wind farm (at the end of Lake Ontario, near the start of the St. Lawrence Seaway) suggest they are often quite audible from two miles, and occasionally somewhat audible at five to seven miles.  While there is often an assumption that wave sounds will easily drown out distant turbines, it’s likely that people living somewhat inland from the shoreline in otherwise very quiet rural areas would be the most affected by offshore turbine sounds.

Litchfield NY is considering a relatively flexible, while stringent, local ordinance to govern construction of wind farms.  As proposed by a committee of residents charged by the Town Council, the ordinance would avoid strict setback or decibel limits, and instead require easements to be obtained from all residents within 6500 feet of a turbine (just under a mile and a quarter).

The proposed ordinance now goes to the Council for consideration, where some changes are expected to be made.  Involving all neighbors who may be affected by new wind turbines could be a very effective approach, as both studies and experience shows that when people are involved in the decision to move forward with a wind farm (and compensated financially, or feel shared ownership), they are far less likely to have negative reactions and experiences.  I’m sure that the distance at which easements are required will be a sticking point for all concerned; as proposed, it encompasses a large grey area (from roughly 3500-6500 feet) in which acoustic effects are likely to be minimal, yet possible a small proportion of the time.  If the easements don’t effectively become vetoes, it’s quite likely that being involved in the decision could play a key role in this range.  Closer than a half mile or so, the proposed easements may well be sometimes used as a veto, as at least a few residents are apt to feel that the risk of noise issues is not outweighed by financial benefits in the project.  Still, the easement approach has many benefits over a strict decibel or setback limit, assuring that the developer is engaged with everyone who may be affected by the project.

An article in Der Spiegel reveals that the environmental impact study at a 12-turbine wind farm 30km off the coast of Germany has reported that during construction of the turbines, porpoises avoided an area in a 20-mile radius of the two-square mile construction site.  Harbor porpoises are well known to be more sensitive to sound than many ocean creatures, and may serve as a sort of “canary in the construction zone,” their stark behavioral response standing as an indicator of noise levels that likely interfere with other animals, as well.

Future construction could affect a far larger number of animals than the relatively modest construction that has taken place so far. (click to see larger Der Spiegel image)

This one passed under my radar in January, but has some potentially interesting implications for people working to minimize the negative effects of wind farms on wildlife and humans, in that the developer agreed to shut turbines down at night, at least temporarily.  In December, a Federal court halted construction of the Beech Ridge wind farm in West Virginia, because Indiana Bats, officially listed Endangered Species, live nearby, and the developers had not obtained the necessary Incidental Take Permits that govern activities that may impact such species.  In a settlement announced in January, Beech Ridge Energy, a subsidiary of Invenergy, agreed to forego construction of 24 turbines closest to the bat caves, while receiving approval to operate the 40 turbines that are already constructed, to complete construction of 27 more, and to move forward on planning for an additional 33 units (though the units not yet constructed may not begin operating until the ITP is received).

Most strikingly, the company agreed that all operational turbines will be shut down at night from April to November 15, when the bats are out and about.  During the hibernation season, from mid-November through March, the turbines can operate around the clock.  Future operating conditions, including the need for night-time curtailments, will be subject to the determination of the US Fish and Wildlife Service Incidental Take Permits. Noise is not the issue here, but rather bat mortality near wind turbines, likely caused by rapid changes in air pressure.

It is encouraging to see the viability of operational restrictions being experimented with, and accepted by  both industry and environmental groups as a way forward through a contentious issue.  Indiana Bats are not known to travel in the area of the wind farm, though the proximity of their caves suggests they may; monitoring done by the company was challenged in the lawsuit as insufficient.  Ongoing acoustic surveys will help clarify how common they are, and the USFWS may decide that night time restrictions are unnecessary.  As part of this settlement, the company agreed not to appeal the judge’s decision, and the environmental plaintiffs agreed not to appeal the eventual ITP decision by USFWS.

Happy talk all around after the agreement: Dave Burhman, spokesman for MCRE, said, “We believe our actions have sent a vitally needed message to the wind industry as a whole. Renewable energy projects do not get a pass on existing laws designed to protect endangered species and the natural environment. And although industrial wind turbines will now spin atop some of Greenbrier County’s highest ridges, they will forever be banned on those ridges in closest proximity to endangered Indiana bat caves.”  And Joe Condo, general counsel for the company, agreed that “We are very pleased to have reached an agreement that allows us to move forward with creating clean, renewable energy in Greenbrier County while at the same time meeting the goals of important wildlife conservation efforts.

Sources:
Beckley Register-Herald, 1/27/10
West Virginia Highlands Conservancy, 2/10/10

As noted in a previous post, a recent report by the Chief Medical Officer of Health (CMOH) in Ontario focused on the narrow question of whether there is a “direct causal link between wind turbine noise and adverse health effects” experienced by some wind farm neighbors.  Based on a review of published research, the answer was, “no.”  This week, two of the people who were on the review committee providing feedback on the report as it moved from draft to final form noted that the final version dropped a section that some reviewers had urged be included, which would have more directly addressed the actual experiences of communities near wind farms.

Dr. Hazel Lynn, the Grey Bruce medical officer of health, told the Owen Sound Sun-Times, “The whole section that a couple of us really wanted in there on community health and community disruption went. It’s not in there. I suspect politically she can’t criticize another ministry, so I was a little disappointed.”

“I think it’s a fair comment that there is other material that could have been in the report and wasn’t,” added Dr. Ray Copes, the director of environmental and occupational health at the Ontario Agency for Health Protection and Promotion and another member of the committee that reviewed drafts of the report. Copes said there are “really important and quite legitimate” questions about wind farms that he and Lynn thought should be discussed, but “I guess the CMOH’s report wasn’t the place for it.”

Both Lynn and Copes stressed that they agreed with the report as far as it went, and that direct noise levels and sound qualities of wind farms don’t appear likely to directly cause health problems.  Lynn noted that there is an “association” between wind farms and some health effects, but that these effects also occur elsewhere; still, she said, “Basically, I think they (wind farms) disrupt communities if they’re not properly planned and instituted and when you disrupt people’s communities they get sick.” There is evidence to back that position up, she added, but “that doesn’t come through very clearly” in King’s report. Likewise, Copes stressed that the idea of a unique quality in wind farm noise causing a new set of health problems seems “implausible,” yet he also stressed (as did AEI) that the report highlights the need for more direct measurements of sound levels around wind farms.  Such measurements will add much-needed ground truthing to the sound models currently used in siting decisions, and could provide more concrete data to use in assessing both noise complaints and health concerns.

An impressive array of 76 acoustic monitoring buoys is planned to be deployed in Scotland’s Moray Firth this summer, to listen in on local populations of dolphins, porpoises, whales, and seals.  Scientists from Aberdeen University will place the recording devices up to 70 miles offshore, expanding on work carried out last summer on a smaller scale.  Dr. Paul Thompson, one of the lead researchers, explains: “This will help us get a better understanding of the distribution of particular species. We will be looking at the impact primarily of oil and gas exploration, but also the development of wind farms. During construction phase of these developments, it can be quite noisy and affect marine mammals. It will allow us to get a better understanding of how they use different parts of the Moray Firth and to understand what parts are most important” to each species.  Read more at The Scotsman.

In recent months, several lawsuits and formal complaints have been filed, claiming unlawful nuisance and/or impacts on property values and quality of life near wind farms.  Most recently, sixteen residents sued the Michigan Wind I wind farm and its developers, laying out a series of complaints, including (as detailed in the Huron Daily Tribune):

• Private nuisance from, among other things, sustained and highly annoying audible noise and amplitude modulation in both audible and sub-audible frequencies
• Negligent design of a wind farm, including a noise assessment that estimated only audible noise levels within the dBA range, and did not consider low frequency noise or impulse noise
• Negligent misrepresentation, claiming the wind companies made false representations in board of commissioner and planning commissioner meetings and public hearings when company representatives said the wind farm’s operations would not result in a noise nuisance or cause adverse health effects to adjacent landowners. “(The defendants) were negligent in making these misrepresentations because, as the parties seeking approval to construct a wind turbine farm in Huron County, they had a duty to use reasonable care to provide Huron County and its citizens with both accurate and complete information,” the lawsuit states. The plaintiffs claim the wind companies provided inaccurate and/or incomplete information about the audible turbine noise levels, and no information about low frequency noise, infrasound and/or impulse noise emitted from the turbines.

In Pennsylvania, the Allegheny Ridge Wind Farm settled out of court this week as a lawsuit brought by Todd and Jill Stull was moving toward a jury trial in July.  The suit alleged that the company misrepresented the noise levels that would be generated by assuring residents the noise would e minimal.  The agreement is bound by confidentiality, so no details are available. See earlier coverage of the lawsuit here.

Meanwhile, in neighboring Wisconsin, Read the rest of this entry »

This recording, by one of the wind farm neighbors in Wisconsin who I met when visiting there last fall, is a good, simple taste of the sounds heard from 1500 or so feet away—this one has a predominant jet plane flavor, though often neighbors report a wide variety of sounds that change depending on wind conditions.  Most of these folks have several turbines around their homes; one person told me that he thought he could live with it if the ones closer than a half mile were not there, though another of his neighbors leaned more toward a mile as his comfort zone.  Listening to this selection of sounds, recorded with different cloud covers and wind directions, I could get a sense of why some people find hearing this incredibly disruptive and intrusive, while others say they are not much bothered; this disparity of reaction is one of the fundamental paradoxes of wind farm noise issues.  

Give a listen…..turn it up and down to get a feel for it at different sound levels or distances (or to simulate how it feels to people with different degrees of sensitivity/attention to the sound)…..imagine it lasting far longer than this three minute taste—which may well make it more torturous, or might allow it to sink into the background of your awareness…..if this sound, at a moderate level, or turned down very low to be just audible, was happening in your neighborhood, how would it be for you?

Over the past week or so, two reports from Ontario have spurred a fair amount of notice and comment among those following wind development issues.  First, the provincial health office responded to the public’s concerns about health problems reported by some wind farm neighbors, framing its answer carefully and narrowly:  “According to the scientific evidence, there isn’t any direct causal link between wind turbine noise and adverse health effects,” said Dr. Arlene King, Ontario’s Chief Medical Officer, as reported by the Vancouver Sun.  Since the report’s focus was to asses peer-reviewed science, its authors did not incorporate any reference to the experiences or changes in sleep patterns or health of real-life neighbors of wind farms who have reported negative impacts since the turbines began turning. It is no real surprise that the sound levels near wind farms aren’t loud enough to directly cause physiological damage or effects, though it seems clear that annoyance and sleep disruption may well contribute to health effects in some people; the report acknowledges the likelihood of some annoyance, and notes too that while low-frequency sound is below generally perceptible levels, and generally no louder than naturally-occuring low-frequency sound sources, some people who hear these frequencies better than most may be bothered.  While the report itself is brief and lacks the detail of the recent industry-funded AWEA/CanWEA report, which reached similar conclusions in addressing the same narrowly-focused questions, King’s report frames the results with two crucial but under-reported observations:

• By way of introduction, the report explicitly states a simple fact that is rarely acknowledged: “Little information is available on actual measurements of sound levels generated from wind turbines and other environmental sources. Since there is no widely accepted protocol for the measurement of noise from wind turbines, current regulatory requirements are based on modelling.”  Indeed, sound models are used to determine what distance a turbine needs to be from nearby homes in order to meet local statutory noise limits (which stand at 40dB in Ontario).
• And in its final words, the report stresses the corollary to this observation: “The review also identified that sound measurements at residential areas around wind turbines and comparisons with sound levels around other rural and urban areas, to assess actual ambient noise levels prevalent in Ontario, is a key data gap that could be addressed. An assessment of noise levels around wind power developments and other residential environments, including monitoring for sound level compliance, is an important prerequisite to making an informed decision on whether epidemiological studies looking at health outcomes will be useful.”

Actual rural ambient noise levels are often very low, so that wind farm noise becomes bothersome at lower levels than industrial or transportation noises prevalent in urban and suburban areas; and, as noted in the body of the report, most of the case studies and other reports of health effects lack any clear information on how loud the turbine sounds are in the homes of those being affected.  So while this report is in large part another seemingly definitive, yet stubbornly partial, assessment of the health effects reported near wind farms, it also lays the groundwork for much-needed on the ground assessment of noise patterns around wind farms. (See this more recent post, regarding a section on community health and disruption that was omitted in the final draft of this report.  And see this critique of the CMOH report, written by several doctors from Canada, the UK, and the US who have been advocating for closer study of these issues)

On a similar note, Ontario Ministry of Environment officials confirmed this week that they do not have the capability to record or assess the noise near wind farms where noise complaints arise.  According to the Windsor Star, “Although hundreds of wind turbines have already been built in Ontario, Michael Parker, district manager for the environment ministry, said staff have not yet been given noise-monitoring equipment. The ministry is responsible for ensuring that wind turbine noise reaching a residence doesn’t exceed 40 decibels, he said.  If a complaint about turbine noise is made to the ministry, two environment officers are sent to the area to listen for the noise and contact the turbine owner, Parker said, noting that the ministry could still intercede with turbine owners even without hard data on the noise levels. In some cases, turbine speeds have been scaled back or the turbine shut down completely.”  In January, the Ministry of Environment issued two Requests for Proposals seeking advice and technical standards to use in assessing wind farm noise. The RFPs said that “The Ministry requires a consultant to assist in the development of a measurement procedure to assess noise compliance of existing wind farms with the applicable sound level limits,” noting that “Unlike typical industrial noise sources, measurement of audible noise from wind turbines in general raises technical challenges.” At that time, the Ministry acknowledged that its “Noise Guidelines for Wind Farms…do not contain a measurement method for assessing the actual noise impact.”

The Morrow County Planning Board ruled this week that the Willow Creek Energy Center, an 80-turbine wind farm, is producing noise levels that violate Oregon’s noise limits, and gave Invenergy, the wind farm’s owner, six months to get the turbines into compliance.  The wind farm began operating in January 2009, and by March, several neighbors within a half mile had raised serious concerns about the noise (see this article for details), including regularly having difficulty sleeping. Noise monitoring then took place, and in January of this year, the Planning Board received the results, which showed that noise levels at four homes sometimes exceeded the limit of 37dB.

There was some contention at that meeting, as neighbors had hired independent noise monitoring consultants, whose records showed more consistent violations than those of the Invenergy-hired consultant; the differences were pegged to the fact that the Invenergy consultant did not record in high wind speeds, contending that the noise gets no louder above wind speeds of 9m/s.  It is unclear from initial news reports whether the wind farm will be required to comply with the noise limits based on the Invenergy sound monitoring protocol, which found excess noise just 10% of the time at one house, and less frequent slight violations at three others, or whether they’ll use the more comprehensive techniques used by the local citizens, which found violations more consistently at two homes (one just over the limit, the other often over 40dB), with one home experiencing excess noise on 22 out of 37 nights.

Carla McLane, Planning Director for Morrow County, noted that while the commission did rule the wind farm was violating state regulations, it found the turbines only crossed the noise threshold at certain times of day and under certain conditions. “Some would want to view it in black and white and if it’s a violation then you have to shut them down,” McLane said.  “Others would want to view it in terms of shade of gray and say it’s not an ongoing and continuous violation. It’s an intermittent violation.”

”I’m not sure how someone can say this is an unusual, infrequent event,” said Kerrie Standlee, one of the neighbors’ noise consultants. “To me, 59 percent (of nights with excess noise) is not occasional or unusual.” Standlee’s noise study also went beyond Invenergy’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.  This last bit of information may offer Invenergy some direction about when they might shut down turbines if they want to avoid the worst of the noise issues, during the six months they have to get into compliance.

The Planning Board struggled with the conflicting approaches, according the the East Oregonian (article archived here). “I have a very hard time coming to a concrete conclusion on which study I feel is accurate,” Commissioner Pamela Schmidt said. “I’m not a licensed engineer in acoustics myself and there’s been so much information I can’t make a decision.”  Invenergy claimed that the background ambient noise varies, so that in higher wind periods, it should be allowed to exceed 36dB; yet, in its permit, it used the 26dB ambient standard, which is the state’s default if measurements are not made ahead of time. Complicating matters more is the fact that, as the East Oregonian noted, “the rule does not direct agencies on how to administer the rule or decide conflicts such as the one between Invenergy and its neighbors. The agency that originally enforced the rule, the Oregon Department of Environmental Quality, has since defunded and destaffed its noise program.”

It’s worth noting that the noise issues seem to be quite pronounced even at sound levels of 40dB.  Oregon’s 36dB limit is among the most conservative in the country; it’s based on being 10dB above average night time ambient noise levels, which have been measured at 26dB.  It appears that noise issues may well be present even when the measured sound levels are at or very near 36dB; this is in synch with reports from elsewhere, which suggest that people accustomed to quiet rural night time soundscapes are quite easily disturbed when turbine noise becomes one of the loudest local sounds, even when absolute noise levels are not extreme. In general, acousticians consider a sound to become readily audible when it is 5dB above ambient, with disturbance considered likely when it reaches 10dB above ambient.

UPDATE, June 2011: The state Land Use Board of Appeals issued a ruling that questioned the county’s interpretation of the 36dB noise limit. In its ruling, LUBA sided with the wind developer, which had said that the state laws allow wind farms to produce up to 10dB more than ambient sound levels; the county had been suggesting that if the developer doesn’t conduct ambient noise studies before construction, they must assume ambient of 26dB (typical night time ambient).  The LUBA decision said that this requirement to choose whether or not to do an ambient study prior to construction did not appear in the state rules, leaving room for companies to show later that measurements of turbine noise levels exceeding 36dB were  made when the ambient was above 26dB.

A private landowner in Clifton, Maine, is hoping to erect four commercial wind turbines on a small ridge known as Pisgah Mountain, and sell the energy to the local utility, Bangor Hydro.  Hearing of negative experiences in other Maine towns, including Mars Hill and Vinalhaven, some local residents are concerned about noise impacts and effects on wildlife.  The town of Clifton has drafted a new ordinance that sets 4000 feet as the minimum distance between a turbine and a neighboring house; this ordinance will go before voters on June 8.  In both other towns, affected families live within 3500 feet of the local turbines.

“What we have on this site is setbacks to the closest residence of a little over 4,300 feet,” says Paul Fuller, who owns the 240 acres where the turbines would be built. “I think we could boast that that is the farthest setback of any wind farm in the state of Maine at this point.”  Several other homes are within a mile to mile and a half of the location.

If this project moves ahead, it would be one of the first to do so with regulatory setbacks of over 1500-1700 feet, which are commonly used in Maine and elsewhere in the US, as developers aim to reach a 45dB limit at homes.  The ordinance allows sound levels of up to 50dB during the day and 40dB at night; past experience would suggest that at this distance, these sound levels are unlikely to be reached, though it is entirely possible that the turbines will be somewhat audible up to a mile or so away at times (night time noise levels in rural areas can be as low as 20-25db).  Some community advocates urge setbacks of a mile or mile and a quarter, to more surely eliminate audible noise issues; this project would be a valuable “guinea pig” for the helping answer the crucial question of where the proper balance lies between wind development and respecting the rural soundscape of small towns.

Read more and see a news clip at WLBZ2.com

England’s primary environmental agency, the Department for Environment, Food, and Rural Affairs (DEFRA), has commissioned a study to improve techniques for assessing wind farm noise.  “There is a possibility that local authorities are not currently investigating complaints about noise from wind farms due to the absence of any formal technical guidance,” an internal document reads. “Defra wishes to let a contract to provide local authorities with a methodology by which to investigate noise from wind farms, to support local authority enforcement of statutory nuisance legislation.”  According to the Telegraph, the report is due out later this year, and should make it easier for local councils to respond to noise complaints.  A recent survey suggests that about one in seven UK wind farms have spurred noise complaints; noise campaigners contend that many people who are bothered do not file formal complaints, since they are rarely acted upon.

(UPDATE, 8/2/10): Apparently, the news report cited above was about a call for proposals, or plans to let the contract; in August, Energy Minister Charles Hendry announced that the consulting firm Hayes McKenzie had been hired to conduct this review of noise assessment techniques.  The firm will begin work in September and is expected to complete its report by the end of the year.

Meanwhile, also in the UK, the Bradford Planning Inspector upheld a ruling by the city Council to deny a permit for building a single large turbine at a factory in town.  The applicant had appealed the denial, since its noise studies showed that that the turbine would be in compliance with the federal noise code ETSU-R-97, which is the only code named in the statutes.  However, the investigating Bradford Council Environmental Health officer used several other noise level methodologies when he visited a similar turbine in Norfolk. Using World Health Organisation and British Standard guidelines and codes of practice, as well as ETSU-R-97, he came to the conclusion that the Princes Soft Drinks turbine would cause a noise nuisance for nearby residents. The Planning ruling noted that even according to the company’s modeling, “for some dwellings under certain conditions, the emitted turbine noise is likely to lead to complaints. Furthermore, according to WHO standards, there would be times when this noise could result in sleep disturbance, or prove to be a serious annoyance to residents. I find this to be unacceptable.”

Councillor John Ruding said: “I am delighted that the inspector agreed with the local community and their voices have been heard. “These proposals were an experiment on people’s lives which was not acceptable.”  Earlier, at the time that the company appealed the initial denial, another Councillor, James Cairns, had noted, “The Council has done its best. Its officers didn’t believe it was feasible in the area. Bradford is not against wind turbines – if you go up onto the moors, you will see them. But turbines of this size have not been tried and tested in urban areas.”

When the town-owned wind turbine began operating at the Falmouth, MA wastewater treatment facility in March, most townspeople saw it as the most striking example of the town’s far-reaching commitment to sustainability.  Since then, it’s generated about a third of the town’s electricity needs, and a second turbine is being readied for installation nearby this summer.  As noted at a forum on the town’s many energy-savings initiatives, in discussing the second turbine: “The special thing about the site is it’s remote. The nearest home is about 1/3 mile away, which is important in terms of noise and appearance.” (This is just under 1800 feet, or 600 yards.)

But over the few weeks since the first turbine began operating, residents are finding the noise much more disruptive than they’d imagined.  According to the Cape Cod Times, some neighbors who live in the sparsely populated, wooded area around the treatment facility were horrified when they heard the noise. “It’s destroyed our capacity to enjoy our homes,” Kathy Elder said. Elder said the noise surrounds her residence, alternating between a jet’s whine, thunder and a thumping that sometimes can be felt.

The town has received formal complaints from six residents, one of whome, Annie Hart Cool, has gathered over 40 names of people within a mile or so who say they are affected.  She notes that her husband enjoys working in their yard after work, “but when he comes back inside and his head is hurting, you know something’s wrong.”

Assistant Town Manager Heather Harper says that the town has asked Vestas, the turbine manufacturer, to come check whether there are any mechanical issues that may be causing elevated noise levels, and is asking residents to compile records of when the sound is worst, to help the town figure out how to respond. “This has been a community project from the beginning,” Harper said. “We’re genuinely concerned and we take the complaints very seriously.”  At the same time, Harper noted that “We didn’t expect no sound, but it should meet all governmental standards.”  This is, indeed, often the issue: governmental noise standards, which tend to range from 40-50dB, are not always sufficient to avoid negative impacts on the nearest neighbors.

UPDATE: Another local newspaper covers the brewing controversy.

An excellent 3-part series on wind farm development ran this week in the Bismark Tribune. It has a good balance of the excitement and economic benefits that attract farmers to the industry, and well-stated concerns from those who want larger setbacks in order to protect neighbors from noise.  The grey area around health impacts is navigated quite well, with a well-grounded emphasis on sleep disruption; and most strikingly, the piece includes acknowledgement that there is individual variability in how easily people can adapt to a new and potentially intrusive noise source.

Interestingly, there are repeated indications that in this community, as in others, a half mile setback was seen as the “sweet spot” that could accommodate both industry and neighbors; in initial community meetings, there was significant support for a one-mile setback, while a general consensus emerged that a half mile would be tolerable to most people.  Nonetheless, the county decided to go with a third of a mile (1750-foot) setback, which has some community members concerned that the turbines will be audible enough to be disruptive at times.

Wyoming has been at the center of the storm over how much wind farm developers should be subject to limits on development in the name of protecting wildlife habitat, thanks to the hot-button issue of the sage grouse, which has been dancing on the edge of federal endangered species listing for several years. In general, with the exception of bird and bat deaths caused by flying into or near whirling turbine blades, wind farms have been assumed to be benign in relation to wildlife habitat.  The noise made by turbines is considered to be moderate enough to have minimal impact on nearby wildlife (though recent National Park Service research that quantifies the dramatic reductions in listening area caused by small increases in background noise may eventually change this thinking).

This week, the Wyoming Game and Fish Department approved a set of recommendations that will guide the Wyoming Industrial Siting Council on permit applications for major projects in the state, including wind farms numbering at least 30 turbines. Under the guidelines, construction activity will be halted within two miles of an active grouse lek during the mating season each spring, though turbines will be allowed to operate in any location more than a quarter mile from a lek (increased to six tenths of a mile for one species). Restrictions on wind farms within two miles of wildlife refuges were softened in the final draft, which requires simply that developers coordinate with the Game and Fish Department and US Fish and Wildlife Service when building near refuges or state wildlife management areas.  Developers are urged to avoid big game wintering and birthing ranges, but if siting in these areas “cannot be avoided,” then construction activity must cease during the relevant times of year; again, construction is assumed to be a disturbance, while operations are assumed to be benign.

Many ranchers opposed the new rules, citing private property rights, while environmental advocates urged larger buffers, including six-tenths of a mile for all species. “You’ve got one set of concerns saying we don’t have enough restriction, and the other side saying we’ve got way too much,” WGFD deputy director John Emmerich said. “I think we’ve done a credible job of trying to address the needs for wildlife and still accommodate reasonable levels of development.”

Read more at the San Francisco Examiner and Casper Tribune, and download the recommendations here.

“As goes Maine, so goes the Nation?”  While this old political truism has faded in recent decades, the State of Maine is currently blazing trails in carefully considered wind power development.  At the local level, small towns continue to pass moratoriums and strict setback standards.  Most recently, Thorndike became the third town to set a one-mile setback, with the neighboring town of Dixmont taking up a similar ordinance at this week’s town meeting.  Meanwhile, two more towns, Avon and New Vineyard, joined four others who have hit the pause button on any wind farm developments by adopting moratoriums on any permits.  These actions come in the wake of three projects that have generated significant noise issues for neighbors out to as far as 3000-3500 feet; thus, half-mile setbacks are being seen as not enough to avoid risk of disrupting rural lifestyles.

While these towns see the state as being overly aggressive in supporting ridgetop wind farms (abetted by the fact that a former Governor is one of the state’s leading wind developers), when it comes to offshore wind development, the state’s goals will be much more welcome for most coastal communities.  Instead of opening Maine state waters to windfarm leasing, the legislature’s Committee on Utilities and Energy is redrafting controversial ocean windfarm bill LD 1810 to do the very opposite. Under changes to be finalized today at the committee’s 2nd worksession on the bill, “An Act To Implement the Recommendations of the Governor’s Ocean Energy Task Force” will focus Maine instead on constructing floating deepwater windmills on land, and then deploying them at locations ten miles offshore and further, where wind speeds and higher and more consistent and fisheries are less impacted.

The plan received an enthusiastic response from the Maine Lobstermens Association, which has been very concerned about the impacts of any traditional bottom-mounted wind turbines on their activities near shore.  Habib Dagher, who leads the University of Maine’s offshore wind project, offered a timeline for getting deepwater wind energy going off Maine. “Our goal is build our first demonstration floating turbine – a third-scale turbine about 120 feet above the water – next year, and place it in the water the year after in the Monhegan site,” Dagher said. “In 2013 we would build the first 4 or 5 megawatt unit, In 2014 and 2015, a 25 megawatt farm.” He predicted that offshore wind would keep growing: “The next phase is development of a large scale 500 to 1,000 megawatt farm. We have at least one developer interested to do that and have it operational in 2020”

UPDATE: The offshore Maine project will not have its first scale model test unit in the water until 2013.

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.