[These data suggest] that MOE’s 40 dB(A) regulations meet the needs of only 60% of Ontario’s rural population. If MOE were to adopt regulations based on noise not exceeding any receptor point’s lowest pre-existing ambient background level by more than 3 dB(A) by night and 5 dB(A) by day, that could meet the needs of 95% or more of the population.

The resolution of this must fall to our elected representatives: For what percentage of the population is it acceptable to sacrifice health and well-being in order to meet green-energy goals for wind turbines?

Go to: “Bad Vibrations — Where’s the Science?”

Click here for original, which may have been updated.

Harry, Amanda. February 2007. Wind turbines, noise, and health. 32 pp. www.windturbinenoisehealthhumanrights.com/ wtnoise_health_2007_a_barry.pdf
www.wind-watch.org/documents/?p=501

Kamperman GW, James RR. 2008. Simple guidelines for siting wind turbines to prevent health risks. Noise-Con, July 28-31, 2008, Institute of Noise Control Engineering/USA.
www.wind-watch.org/documents/?p=973

Kamperman GW, James RR. 2008. The “How To” guide to siting wind turbines to prevent health risks from sound. 44 pp. www.windturbinesyndrome.com
www.wind-watch.org/documents/?p=990

National Research Council. 2007. Environmental Impacts of Wind-Energy Projects. The National Academies Press, Washington, DC. 185 pp, p. 109
www.wind-watch.org/documents/uploads/ NRC_Wind_Report_050307.pdf

Pedersen E. 2007. Human response to wind turbine noise: perception, annoyance and moderating factors. Dissertation, Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Goteborg University, Goteborg, Sweden. 86 pp.
www.wind-watch.org/documents/?p=528

Pedersen E, Bouma J, Bakker R, van den Berg GP. 2008. Response to wind turbine noise in the Netherlands. J Acoust Soc Am 123(5): 3536 (abstract).
www.wind-watch.org/documents/?p=1095

Pedersen E and Persson Waye K. 2004. Perceptions and annoyance due to wind turbine noise – a dose-response relationship. J Acoust Soc Am 116(6): 3460-70.
www.wind-watch.org/documents/?p=821

Pedersen E and Persson Waye K. 2007. Wind turbine noise, annoyance and self-reported health and wellbeing in different living environments. Occup Environ Med 64(7): 480-6.
www.wind-watch.org/documents/?p=821

Phipps, Robyn. 2007. Evidence of Dr. Robyn Phipps, in the matter of Moturimu wind farm application, heard before the Joint Commissioners 8th-26th March 2007, Palmerston North [New Zealand]. 43 pp. www.wind-watch.org/ documents/ wp-content/ uploads/ phipps-moturimutestimony.pdf
www.wind-watch.org/documents/?p=754

Style, P, Stimpson I, Toon S, England R, and Wright M. 2005. Microseismic and infrasound monitoring of low frequency noise and vibrations from wind farms. Recommendations on the siting of wind farms in the vicinity of Eskdalemuir, Scotland. 125 pp. www.esci.keele.ac.uk/ geophysics/ News/ windfarm_monitoring.html
www.wind-watch.org/documents/?p=1098

van den Berg, GP. 2004a. Do wind turbines produce significant low frequency sound levels? 11th International Meeting on Low Frequency Noise and Vibration and Its Control, Maastricht, The Netherlands, 30 August to 1 September 2004.
www.wind-watch.org/documents/?p=27

van den Berg, GP. 2004b. Effects of the wind profile at night on wind turbine sound. Journal of Sound and Vibration 277: 955-970.
www.wind-watch.org/documents/?p=25

van den Berg, GP. 2005. The beat is getting stronger: The effect of atmospheric stability on low frequency modulated sound of wind turbines. Journal of Low Frequency Noise, Vibration, and Active Control, 24(1): 1-24.
www.wind-watch.org/documents/?p=1092

van den Berg, GP. 2006. The sound of high winds: The effect of atmospheric stability on wind turbine sound and microphone noise. PhD dissertation, University of Groningen, The Netherlands. 177 pp. irs.ub.rug.nl/ ppn/ 294294104
www.wind-watch.org/documents/?p=1010

van den Berg GP, Pedersen E, Bakker R, Bouma J. 2008a. Wind farm aural and visual impact in the Netherlands. J Acoust Soc Am 123(5): 3682 (abstract).
www.wind-watch.org/documents/?p=1094

van den Berg GP, Pedersen E, Bouma J, Bakker R. 2008b. Project WINDFARMperception: visual and acoustic impact of wind turbine farms on residents. Final report, June 3, 2008. 63 pp. Summary: umcg.wewi.eldoc.ub.rug.nl/ FILES/ root/ Rapporten/ 2008/ WINDFARMperception/ WFp-finalsummary.pdf
www.wind-watch.org/documents/?p=903

Preview “Wind Turbine Syndrome”, by Dr. Nina Pierpont.

Halmstad University/School of Business and Engineering (SET)

Proceedings of the 7th European conference on noise control, EURONOISE, June 29th — July 4th, 2008, Paris, France

Download “Industrial Wind Factories in George Washington National Forest”

Interview with Scott Smrynka, dairy farmer, Lincoln Township, Wisconsin. See transcript below (again, thanks to Better Plan).

[ Click here to view or download the entire "Wisconsin Wind" video (1 hr 49 min) ]

Scott Smrynka speaking about stray voltage trouble on his farm: [Video image: an ohm reader with flickering numbers] This is a five hundred ohms resistor here, this wire is hooked to my stall, this white wire is a remote ground rod way across way, way away from the buildings. So I can go shut the power off across the road and this will still read the same. So it’s coming out of the earth. And I’m four wired. When I shut my power off all four wires are disconnected. So my ground and neutral don’t even come to the farm either.

This is coming out of the earth getting on my stalls, and this is where the cows are living.

Q: What kind of impacts are you having?

Low milk production, health issues, reproduction problems, cows dying of cancer and stuff like that. And more of it. More than normal. This [points at ohm meter] before we started was 5000. When the windmills went on, that was 5000. And we’ve got it this low. By doing a lot of different things that I’m going to keep to myself.

The utility has been out on this farm numerous times. Every time they come in this yard. An hour before they come in this yard [points to ohm meter] this goes to zero. Before they even do anything. And then when they leave, maybe a day or the weekend, it goes back to whatever is coming out of the earth. So they can clean this up. It’s just they can’t keep it clean, for one thing. Can’t keep it low enough for one thing. You’re just battling with them all the time.

Another thing, our meter’s right there for– we check the water meter for how much water the cows drink. Cows this size, when we were milking before, we were getting 30-35 gallons of water in these cows. Now we struggle to get over 22 gallons a cow. That’s the milk production. You can’t get the water in them. You need the water to cleanse their body, their whole system –digest the food.

Every animal that dies on this farm gets autopsied. Calf, cow– tear it apart, we want to know what’s wrong. What’d she die from. What happened? And what we’ve seen– the organs– the heart was inflamed– the kidneys– the liver blackened and a lot of– the biggest thing that seems to come out is the colostrum salmonella. They die from it. It’s frustrating. What I’ll tell you to make it very simple is it microwaves you from the inside out. That’s what it’s doing to our cattle.

You say, what human issues does it have? I’m no scientist, but what I see in my cows gotta be affecting me too, and my family. I mean what you’re seeing with these cows– reproduction and production– they had the Univeristy vets out her from Madison, saying my cows only laid down 8.3 hours a day and a cows supposed lay down 12 to 14 to 16 hours a day– I’m only getting half that. It’s affecting– that’s why they ain’t reproducing. The reproduction isn’t there, the production isn’t there. So 8.3 hours. That’s all these cows lay down. They don’t want to lie down. That’s why I’m losing the milk production. And another thing we had a university vet come out here and stood right here by the return alley as the cows were being milked and said 33% of our cows are lame. We’ll if they ain’t laying down, they’re going to be lame, right? And then you ask these vets and the utility and that, ok, you had these studies done, and that’s what they’re saying– what are we going to do?

They’re saying my stall design needs to be changed. I got three layers of rubber mattresses under these cows feet. How can I get it any softer. Stall design. You can see there’s nothing in front of them. When they lunge they can get up and do whatever they want. And the other two groups of cows are in sand bedding, so if they’re in sand bedding that’s as soft as you’re going to get. So I told them I wouldn’t buy it.

Then the vets asked me, what do you think it is? I said, “Right here.” [pointing to the ohm meter] You get that down and I guarantee these cows will lay down. Because at times we get it low. Really low.

And there’s times when I got in trouble here, three four years ago, I clipped a lot of ground rods across the road. Stayed like that for 14 months. This meter went way down. My cows went up twenty pounds of milk, these issues weren’t here. Until the utility found it, put it back together.

Q: So you know where it’s coming from.

I know where it’s coming from. I have no doubt in my mind. And I had a 30,000 pound heard average before those windmills were up. Now I struggle to get 20,000.

So I mean, it’ all boils down to stray voltage– or I’m not going to call this stray voltage– ground currents or electrical pollution. There’s more to this story than they let the people know. There’s a lot we don’t know. It’s amazing. I just came across it while I was catching this stuff, and trying to figure out and solve my problem, using transformers, you name it. So I mean, what you guys gotta do is do a lot of research. If they’re there [the wind developers], pounding on the door, and got permits from landowners and all that, then you’re kind of screwed. Because their foot’s in the door already. You gotta do this before they get their foot in the door.

Interview with Arlin Montfils, Supervisor, Lincoln Township, Wisconsin. See transcript below (again, thanks to Better Plan).

[ Click here to view or download the entire "Wisconsin Wind" video (1 hr 49 min) ]

Arlin Montfils: We knew nothing, really, about them. The company said, well– they imposed an 800 foot set-back from the nearest resident.

Q: Not from their property line, but from their home.

The nearest resident. I believe that’s what it was. I haven’t looked back for sometime, but in my opinion that was way too close, we had people that complained: noise, noise, and noise.

And it wasn’t at high wind speeds. It was at low wind speeds like lets say ten to fifteen miles an hour, something like that, that’s where the most noise was coming in.

The decibel level [limit] was 50 decibels, we knew nothing about it. In my opinion it should have been 45. They threw out that number and they said you and I talking is 50 decibels and that’s probably true. I don’t dispute that. And they probably haven’t exceeded this 50 decibel level, but it’s constant it can go on for– well, you know the wind– it can go on for 24 hours or more and that’s when you start getting complaints because it never goes away and that’s when it gets irritating.

With this noise complaint, they set up a toll-free number you could call that day or night, twenty-four hours a day and file a complaint. Stating that there’s noise and it sounded like this or it sounded like that and what time of the day and approximate wind speeds, and that went on for about a year, I would say, that they had this toll free number up. Then at the end of the year what they did was contact these residential home-owners and offer to buy their property. Offer to buy their homes.

Q: They did offer to buy them?

Oh yeah. They bought two homes. There were five basic complaints all the time. So they bought two of the homes, tore them down. One party got a divorce so another person lived there, didn’t bother her, what ever. The two other places, they brought a lawsuit against WPS, they settled, I think they settled out of court, because if they had settled in court it would have been public record and we were not able to find out what they settled for.

Q: Are they still living there?

They are still living there. Yes.

Q: Now you mentioned, the public utility– two of [the houses] they bought and they tore them down. Why do you think they tore them down rather than try to resell them?

If they sold them they might have sold them to someone who would still complain. And they didn’t want complaints, I guess. One of those situations where the person got a divorce, and he came out on top by selling it to them, and the other party just sold the house.

Q: Being a public official you hear a lot of things. Do you feel that the complaints from the property owners were valid?

Oh yeah. Sure.

Q: They were valid.

Yeah. They’ll say you only got one home complaining or two well the turbines are right here, there are eight of them, there’s only two homes close by. So you had two complaints. So they say, “You only had two complaints,” but if there was more homes– if there was ten homes, you’d have ten complaints.

Q Do you expect to have anymore development for wind turbines in this area?

No. They companies that put them– the utilities– won put them up anymore. But if they were to do it, they would have private companies do it and then buy the electricity back from them.

Q: Why do you think they are getting away from the development themselves and having a company do it–

They want to be good neighbors, so if they don’t do anything about a complaint they are not good neighbors. So if they deal with a private company, the private company would have to deal with all the complaints or issues or what have you, they would have no problem. That’s what they told us. It’s a lot easier to have a private company put them up rather than themselves.

Q: Getting back to the economic side of this did this development, other than bringing revenue in to the local township and county and the landowners, did it bring any jobs here?

When they were first building, a private contractor dug the base and I’m sure they got the concrete for the bases from a local supplier.

Q: Other than construction were there any jobs created?

No. No. They do have– they found their own personnel for maintenance, you know. And if there is a problem with that they come in with their own companies or who ever they have

Q: Specialized?

Basically, they come in with a high crane you know. And we don’t have that. Nobody around here has that. So they have to come in with it. Private company from someplace. I don’t know where.

Q: Have there been any maintenance issues with the turbines?

I believe there is. We get a report every year as to what was replaced. Basically it’s the generators and the oil sometimes a bearing goes out, they have to replace that. It’s all them. We have nothing to do with that, you know.

Q: Can you tell us a little bit about the benefits to the community or pros and cons that you can see on both sides of this for your community?

Financially it’s the biggest benefit there was for the township.

Q: For the township?

Yes.

Q: Was it a needed revenue stream?

No. We could have done without it.

Q: But it was nice having extra–

Oh, absolutely.

Q: It’s always nice to have extra money.

Right. Yeah.

Q: So the money, the financial aspect of it is a benefit. What about cons? Is there any negative impact?

We had a person that complained a lot about stray voltage. The party himself spent a lot of money trying to control the stray voltage on his place.

Q: Did he have livestock?

Oh yeah. He’s a dairy farmer.

Q: Big dairy farmer?

Oh yeah. A hundred and fifty cows he might milk plus other animals, you know. He spent a lot of money, you know. He couldn’t alleviate it, but could control it.

Q: Did the development company, did the public utility do anything to assist him with that?

No. We did have the Public Service Commission of Wisconsin come in and do testing, and their tests came back saying the towers are within guidelines– I don’t know what the guidelines are– that they did not exceed the guide lines toward stray voltage. [The farmer's] concern was they did.

Q. Have you heard of any health concerns people had because they are living next to them.

Well this party that put their home up for sale– they thought their kid was getting too many headaches.

So they did have Madison Gas and Electric, the owners of those utilities, they did come in and do a study, and what ever their findings were, they said they did not exceed guidelines for homes, for residential homes for as far as stray voltage went. That’s as far as it went.

Q: My other question here is information made available on the internet. There’s a lot of information about Lincoln township that’s available on the internet now for people to view and consider. What are your thoughts about that information, is it factual information? An accurate representation of what’s taken place here?

I have not seen it. I don’t have internet access right here, you know. But I know about it. Basically what I’m telling you now, if you want to compare what I’ve said to you to what’s on the internet? Work from there. I think it’s pretty factual, I think they exaggerated on some things, I don’t know which ones it would have been, but, yeah. It’s reasonably accurate I think.

By courtesy of Rock County Tax-Payers for a Better Renewable Energy Plan

Interview with Gerry Meyer, Byron, Fond du Lac County, Wisconsin. See transcript below (again, thanks to Better Plan). Click here for the Meyer family’s daily log of the wind turbine noise and its effects.

[ Click here to view or download the entire "Wisconsin Wind" video (1 hr 49 min) ]

GERRY: Well I’ve been keeping a daily log and I think it was March 5th the turbine that is 1560 feet behind our house was turned on. I didn’t know it at first. I walked out of the door and when I walked down the sidewalk and I heard the sound of a jet flying over so I’m looking up in the sky for this jet. Well it wasn’t a jet. It was the turbine going.

So the majority of the time it sounds like a jet going over. Sometimes the whooosh whooosh whooosh of the blades turning around.

We have another turbine that’s about 2800 feet across the road and at times that one is just as loud as the one behind our house. In all we hear five of them from our house.

Q: Have you noticed any change in your quality of life because of the noise, or has anyone in your family noticed any change in their quality of life?

Last Saturday seemed to be the loudest when all five of them were running. At one point I was walking across the yard, I had a little funny feeling, I don’t know, a different feeling inside of my head kind of like after you get off a roller coaster, you’re not completely stable.

We have a 13 year old son we adopted through social services who has a lot of issues, emotional issues, health issues, and a couple days after the turbine started turning– the one behind our house– he had headaches for about three or four days, pretty strong headaches– and he’s on an unusual program at school because of discipline. Level four being the best, he can stay in the class room with other students. Level three he’s in a special ed room, level two he’s in the special ed room but segregated from the other children and level one he’s in a different room, kind of like solitary confinement. And after these headaches he went from level four down to level one and two for almost two weeks.

He’d come home and tell us, he’d tell the principal, tell his teachers that he felt his head was spinning a hundred miles an hour. So we can’t prove at this time that it’s from the turbines but we’re thinking there’s a connection.

When we first heard that the turbines were going to be built in our area my wife was especially concerned because our son is kind of like Radar on “Mash”– he hears a siren, tells us there’s a siren, but we don’t hear any siren, then a couple of seconds later sure enough the fire department is out or there’s an ambulance run taking place.

Q: What has the interaction with the local officials– either township or county– been with its residents?

I think most of the ground work had taken place before the residents were aware. I think the energy people had visited the counties, the towns, and it was cut and dry. And then there was a few local residents who caught wind of it and attended meetings and tried to tell the town officials– here it’s a very small township– there’s a chairman and two supervisors– we’re in the town of Byron, Fond du Lac County, it’s the southern edge of Fond du Lac County.

Q: When you talk to the neighbors in this area, what’s the general consensus, are they satisfied with the project?

I think some of the farmers feel they were mislead. And after they signed the contract the energy company pretty much walked all over their land. They didn’t build roads in a common sense manner, they stayed off of fence lines– in some cases they went along the fence line and then cut diagonally across the field. I was at the first meeting when the energy company came and said maybe there would be an acre to two acres of land being disturbed on each site. And if you take the width of the road and the distance– some of them are a quarter to a half mile off the main road, they’re disturbing quite a bit of land.

Q: Are there a lot of homes out here that turbines are situated close to?

I would say yes. The majority of the turbines would be close to homes. The set back is 1000 feet. However we’re 1500 feet and 2400 feet and we hear them and to me they are a real nuisance. And 2500 feet should be a minimum.

Q: Under state guidelines they can come closer to your home.You’re already being affected by the distance they’re at now. At a thousand feet, what do you think, would they be unbearable?

I would think, in time, from what I’ve heard, that the low frequency noise, something we may not hear or be aware of, but it’s in the air, and our bodies feel it even though sometimes consciously we’re not hearing or feeling it. There’s one that’s about three quarters of a mile from my house, last Friday my son woke up at 1:30, I saw the light on and I sent him to bed, and I could hear something, I went into our family room and I could hear Turbine #6 which is three quarters of a mile away, inside my house. To me, that shouldn’t be.

Download ‘The “how to” guide to criteria for siting wind turbines to prevent health risks from sound’

• George W. Kamperman, INCE Bd. Cert. Emeritus, INCE Kamperman Associates, Inc., george@kamperman.com
• Richard R. James, E-Coustic Solutions, rickjames@e-coustic.com

Rev. 1.0, July 27, 2008

Industrial scale wind turbines are a familiar part of the landscape in Europe, U.K., and other parts of the world. In the U.S., however, similar industrial-scale wind energy developments are just beginning operation. The presence of industrial wind projects will increase dramatically over the next few years given the push by the Federal and state governments to promote renewable energy sources through tax incentives and other forms of economic and political support. States and local governments in the U.S. are promoting what appear to be lenient rules for how industrial wind farms can be located in communities, which are predominantly rural and often very quiet. Studies already completed and currently in progress describe significant health effects associated with living in the vicinity of industrial grade wind turbines. This paper reviews sound studies conducted by consultants for governments, the wind turbine owner, or the local residents for a number of sites with known health or annoyance problems. The purpose is to determine if a set of simple guidelines using dBA and dBC sound levels can serve as the “safe” siting guidelines. Findings of the review and recommendations for sound limits will be presented. A discussion of how the proposed limits would have affected the existing sites where people have demonstrated pathologies apparently related to wind turbine sound will also be presented.

… Our review covered the community noise studies performed in response to complaints, research on health issues related to wind turbine noise, critiques of noise studies performed by consultants working for the wind developer, and research/technical papers on wind turbine sound immissions and related topics. The papers are listed in Tables 1-4.

Table 1 — List of Studies Related to Complaints

• Resource Systems Engineering, Sound Level Study — Ambient & Operations Sound Level Monitoring, Maine Department of Environmental Protection Order No. L-21635-26-A-N, June 2007
• ESS Group, Inc., Draft Environmental Impact Statement For The Dutch Hill Wind Power Project — Town of Cohocton, NY, November 2006
• David M. Hessler, Environmental Sound Survey and Noise Impact Assessment — Noble Wethersfield Wind Park — Towns of Wethersfield and Eagle NY, For: Noble Environmental Power, LLC, January 2007
• George Hessler, “Report Number 101006-1, Noise Assessment Jordanville Wind Power Project,” October 2006
• HGC Engineering, “Environmental Noise Assessment Pubnico Point Wind Farm, Nova Scotia, Natural Resources Canada Contract NRCAN-06-0046,” August 23, 2006
• John I. Walker, “Sound Quality Monitoring, East Point, Prince Edward Island” by Jacques Whitford, Consultants for Prince Edward Island Energy Corporation, May 28, 2007

Table 2 — List of Studies Related to Health

• Nina Pierpont, “Wind Turbine Syndrome — Abstract” from draft article and personal conversations. www.ninapierpont.com
• Nina Pierpont, “Letter from Dr. Pierpont to a resident of Ontario, Canada, re: Wind Turbine Syndrome,” Autumn 2007
• Amanda Harry, “Wind Turbine Noise and Health” (2007)
• Barbara J. Frey and Peter J. Hadden, “Noise Radiation from Wind Turbines Installed Near Homes, Effects on Health” (2007)
• Eja Pedersen, “Human response to wind turbine noise — Perception, annoyance and moderating factors, Occupational and Environmental Medicine,” The Sahlgrenska Academy, Gotenborg 2007
• Robin Phipps, “In the Matter of Moturimu Wind Farm Application, Palmerston North, Australia,” March 2007
• WHO European Centre for Environment and Health, Bonn Office, “Report on the third meeting on night noise guidelines,” April 2005

Table 3 — List of Studies That Review Siting Impact Statements

• Richard H. Bolton, “Evaluation of Environmental Noise Analysis for ‘Jordanville Wind Power Project’,” December 14, 2006 Rev 3
• Clifford P. Schneider, “Accuracy of Model Predictions and the Effects of Atmospheric Stability on Wind Turbine Noise at the Maple Ridge Wind Power Facility,” Lowville, NY — 2007

Table 4 — List of Research and Technical papers Included in Review Process

• Anthony L. Rogers, James F. Manwell, Sally Wright, “Wind Turbine Acoustic Noise,” Renewable Energy Research Laboratory, Dept. of ME and IE, U of Mass, Amherst, amended June 2006
• ISO. 1996. Acoustics — Attenuation of sound during propagation outdoors — Part 2: General method of calculation. International Organization of Standardization. ISO 9613-2. p. 18
• G.P. van den Berg, “The Sounds of High Winds — the effect of atmospheric stability on wind turbine sound and microphone noise,” Ph.D. thesis, 2006
• Fritz van den Berg, “Wind Profiles over Complex Terrain,” Proceedings of Second International Meeting on Wind Turbine Noise, Lyons, France, Sept. 2007
• William K. G. Palmer, “Uncloaking the Nature of Wind Turbines — Using the Science of Meteorology,” Proceedings of Second International Meeting on Wind Turbine Noise, Lyons, France, Sept. 2007
• Soren Vase Legarth, “Auralization and Assessment of Annoyance from Wind Turbines,” Proceedings of Second International Meeting on Wind Turbine Noise, Lyons, France, Sept. 2007
• Julian T. and Jane Davis, “Living with aerodynamic modulation, low frequency vibration and sleep deprivation — how wind turbines inappropriately placed can act collectively and destroy rural quietitude,” Proceedings of Second International Meeting on Wind Turbine Noise, Lyons, France, Sept. 2007
• James D. Barnes, “A Variety of Wind Turbine Noise Regulations in the United States — 2007,” Proceedings of Second International Meeting on Wind Turbine Noise, Lyons, France, Sept. 2007
• M. Schwartz and D. Elliott, “Wind Shear Characteristics at Central Plains Tall Towers,” NREL 2006
• IEC 61400 “Wind turbine generator systems, Part 11: Acoustic noise measurement techniques,”.rev:2002

After reviewing the materials in the tables; we have arrived at our current understanding of wind turbine noise and its impact on the host community and its residents. The review showed that some residents living as far as 3 km (two (2) miles) from a wind farm complain of sleep disturbance from the noise. Many residents living one-tenth this distance (300 m. or 1000 feet) from a wind farm are experiencing major sleep disruption and other serious medical problems from nighttime wind turbine noise. The peculiar acoustic characteristics of wind turbine noise immissions cause the sounds heard at the receiving properties to be more annoying and troublesome than the more familiar noise from traffic and industrial factories. Limits used for these other community noise sources do not appear to be appropriate for siting industrial wind turbines. The residents who are annoyed by wind turbine noise complain of the approximately one (1) second repetitive swoosh-boom-swoosh-boom sound of the turbine blades and “low frequency” noise. It is not apparent to these authors whether the complaints that refer to “low frequency” noise are about the audible low frequency part of the swoosh-boom sound, the one-hertz amplitude modulation of the swoosh-boom sound, or some combination of both acoustic phenomena.

To assist in understanding the issues at hand, the authors developed the “conceptual” graph for industrial wind turbine sound (Figure 1). This graph shows the data from one of the complaint sites plotted against the sound immission spectra for a modern 2.5 MWatt wind turbine; Young’s threshold of perception for the 10% most sensitive population (ISO 0266); and a spectrum obtained for a rural community during a three hour, 20 minute test from 11:45 pm until 3:05 am on a windless June evening in near Ubly, Michigan a quiet rural community located in central Huron County. (Also called: Michigan’s Thumb.) It is worth noting that this rural community demonstrates how quiet a rural community can be when located at a distance from industry, highways, and airport related noise emitters.

During our review we posed a number of questions to ourselves related to what we were learning. The questions (italics) and our answers are:

Do National or International or local community Noise Standards for siting wind turbines near dwellings address the low frequency portion of the wind turbine’s sound immissions? No! State and Local governments are in the process of establishing wind farm noise limits and/or wind turbine setbacks from nearby residents, but the standards incorrectly presume that limits based on dBA levels are sufficient to protect the residents.

Do wind farm developers have noise limit criteria and/or wind turbine setback criteria that apply to nearby residents? Yes! But the Wind Industry recommended residential wind turbine noise levels (typically 50-55 dBA) are too high for the quiet nature of the rural communities and may be unsafe for the nearest residents. An additional concern is that some of the methods for implementing pre-construction computer models may predict sound levels that are too low. These two factors combined can lead to post-construction complaints and health risks.

Are all residents living near wind farms equally affected by wind turbine noise? No, children, people with pre-existing medical conditions, especially sleep disorders, and the elderly are generally the most susceptible. Some people are unaffected while some nearby neighbors develop serious health effects caused by exposure to the same wind turbine noise.

How does wind turbine noise impact nearby residents? Initially, the most common problem is chronic sleep deprivation during nighttime. According to the medical research documents, this may develop into far more serious physical and psychological problems

What are the technical options for reducing wind turbine noise immission at residences? There are only two options: 1) increase the distance between source and receiver; and/or 2) reduce the source sound power immission. Either solution is incompatible with the objective of the wind farm developer to maximize the wind power electrical generation within the land available.

Is wind turbine noise at a residence much more annoying than traffic noise? Yes, researchers have found that “Wind turbine noise was perceived by about 85% of the respondents even when the calculated A-weighted SPL were as low as 35.0-37.5 dB. This could be due to the presence of amplitude modulation in the noise, making it easy to detect and difficult to mask by ambient noise.” [JASA 116(6), December 2004, pgs 3460-3470, "Perception and annoyance due to wind turbine noise-a dose-relationship" Eja Pedersen and Kerstin Persson Waye, Dept of Environmental Medicine, Goteborg University, Sweden]

Why do wind turbine noise immissions of only 35 dBA disturb sleep at night? This issue is now being studied by the medical profession. The affected residents complain of the middle to high frequency swooshing sounds of the rotating turbine blades at a constant repetitive rate of about 1 hertz plus low frequency noise. The amplitude modulation of the swooshing sound changes continuously. The short time interval between the blade’s swooshing sounds described by residents as sometimes having a thump or low frequency banging sound that varies in amplitude up to 10 dBA. This may be a result of phase changes between turbine emissions, turbulence, or an operational mode.. The assumptions about wall and window attenuation being 15 dBA or more may not be sufficiently protective considering the relatively high amplitude of the wind turbine’s low frequency immission spectra.

What are the typical wind farm noise immission criteria or standards? Limits are not consistent and may vary even within a particular country. Example criteria include:

• Australia: the lower of 35 dBA or L₉₀ + 5 dBA
• Denmark: 40 dBA
• France: L₉₀ + 3 (night) and L₉₀ + 5 (day)
• Germany: 40 dBA
• Holland: 40 dBA
• United Kingdom: 40 dBA (day) and 43 dBA (night) or L₉₀ + 5 dBA
• Illinois: 55 dBA (day) and 51 dBA (night)
• Wisconsin: 50 dBA
• Michigan: 55 dBA

Note: Illinois statewide limits are expressed only in nine contiguous octave frequency bands with no mention of A-weighting for the hourly leq limits. Typically, wind turbine noise just meeting the octave band limits would read 5 dB below the energy sum of the nine octave bands after applying A-weighting. So the Illinois limits are approximately 50 dBA (daytime 7 AM to 10 PM) and 46 dBA at night, assuming a wind farm is a Class C Property Line Noise Source.

What is a reasonable wind farm sound immission limit to protect the health of residences? We are proposing an immission limit of 35 dBA or L_90A + 5 dBA, whichever is lower, and a C-weighted criteria to address the affected resident’s complaints of wind turbine low frequency noise: For the proposed criteria the dBC sound level at a receiving property shall not exceed L_90A + 20 dB. In other words, the dBC operating immission limit shall not be more than 20 dB above the measured dBA (L_90A) pre-construction nighttime background sound level. A maximum not-to-exceed limit of 50 dBC is also proposed. … The World Health Organization and others have determined a sound emitter’s noise that results in a difference between the dBC and dBA value greater than 20 dB will be an annoying low frequency issue.

Is not L_90A the minimum dBA background noise level? This is correct, but it is very important to establish the statistical average background noise environment outside a potentially affected residence during the quietest (10 pm to 4 am) sleeping hours of the night. This nighttime sleep disturbance has generated the majority of the wind farm noise complaints throughout the world. The basis for a community’s wind turbine sound immission limits would be the minimum 10 minute nighttime L_90A plus 5 dB for the time period of 10 pm to 7 am. This would become the Nighttime Immission Limits for the proposed wind farm. This can be accomplished with one or several 10 minute measurements during any night when the atmosphere is classified stable with a light wind from the area of the proposed wind farm. The Daytime Limits (7 am to 7 pm) could be set 10 dB above the minimum nighttime L_90A measured noise, but the nighttime criteria will always be the limiting sound levels.

A nearby wind farm meeting these noise immission criteria will be clearly audible to the residents occasionally during nighttime and daytime. Compliance with this noise standard would be determined by repeating the initial nighttime minimum nighttime L_90A tests and adding the dBC (L_eqC) noise measurement with the turbines on and off. If the nighttime background noise level (turbines off) was found to be slightly higher than the measured background prior to the wind farm installation, then the results with the turbines on must be corrected to determine compliance with the pre-turbine established sound limits. …

Including wind as a masking source in the criteria is one method for elevating the permissible limits. Indeed the background noise level does increase with surface wind speed. When it does occur, it can be argued that the increased wind noise provides some masking of the wind farm turbine noise emission. However, in the middle of the night when the atmosphere is defined as stable (no vertical flow from surface heat radiation) the layers of the lower atmosphere can separate and permit wind velocities at the turbine hubs to be 2 to 2.5 times the wind velocity at the 10m high wind monitor but remain near calm at ground level. The result is the wind turbines can be operating at or close to full capacity while it is very quiet outside the nearby dwellings.

This is the heart of the wind turbine noise problem for residents within 3 km (approx. two miles) of a wind farm. When the turbines are producing the sound from operation it is quietest outside the surrounding homes. The PhD thesis of P.G. van den Berg “The Sounds of High Winds” is very enlightening on this issue. See also the letter by John Harrison in Ontario “On Wind Turbine Guidelines.” …

The simple fact that so many residents complain of low frequency noise from wind turbines is clear evidence that the single A-weighted (dBA) noise descriptor used in most jurisdictions for siting turbines is not adequate. The only other simple audio frequency weighting that is standardized and available on all sound level meters is the C-weighting or dBC. A standard sound level meter set to measure dBA is increasingly less sensitive to low frequency below 500 Hz (one octave above middle-C). The same sound level meter set to measure dBC is equally sensitive to all frequencies above 32 Hz (lowest note on grand piano). It is well known that dBC readings are more predictive of perceptual loudness than dBA readings if low frequency sounds are significant.

We are proposing to use the commonly accepted dBA criteria that is based on the preexisting background sound levels plus a 5 dB allowance for the wind turbine’s immissions (e.g. L_90A +5) for the audible sounds from wind turbines. But, to address the lower frequencies that are not considered in A-weighted measurements, we are proposing to add limits based on dBC. The Proposed Sound Limits are presented in the text box at the end of this paper. For the current industrial grade wind turbines in the 1.5 to 3 MWatt range, the addition of the dBC requirement will result in an increased distance between wind turbines and the nearby residents. For the generalized graphs shown in Figure 1, the distances would need to be approximately double the current distance. This will result in setbacks in the range of 1 km or greater for the current generation of wind turbines if they are to be located in rural areas where the L_90A background sound levels are 30 dBA or lower. In areas with higher background sound levels, turbines could be located somewhat closer, but still at a distance greater than the 305 m (1000 ft.) or less setbacks commonly seen in U.S. based wind turbine standards set by many states and used for wind turbine developments.

Proposed Wind Turbine Siting Sound Limits

1. Audible Sound Limit
1. No Wind Turbine or group of turbines shall be located so as to cause an exceedance of the pre-construction/operation background sound levels by more than 5 dBA. The background sound levels shall be the L_90A sound descriptor measured during a pre-construction noise study during the quietest time of evening or night. All data recording shall be a series of contiguous ten (10) minute measurements. L_90A results are valid when L_10A results are no more than 15 dBA above L_90A for the same time period. Noise sensitive sites are to be selected based on wind development’s predicted worst-case sound emissions (in L_eqA and L_eqC) which are to be provided by the developer.
2. Test sites are to be located along the property line(s) of the receiving nonparticipating property(s).
3. A 5 dB penalty is applied for tones as defined in IEC 61400-11.
2. Low Frequency Sound Limit
   The L_eqC and L_90C sound levels from the wind turbine at the receiving property shall not exceed the lower of either:
1. L_eqC − L_90A greater than 20 dB outside any occupied structure, or
2. A maximum not-to-exceed sound level of 50 dBC (L_90C) from the wind turbines without other ambient sounds for properties located at one mile or more from State Highways or other major roads or 55 dBC (L_90C) for properties closer than one mile. These limits shall be assessed using the same nighttime and wind/weather conditions required in 1.a. Turbine operating sound immissions (L_eqA and L_eqC) shall represent worst case sound immissions for stable nighttime conditions with low winds at ground level and winds sufficient for full operating capacity at the hub.
3. General Clause
   Not to exceed 35 dBA within 30 m. (approx. 100 feet) of any occupied structure.
4. Requirements
1. All instruments must meet ANSI or IEC Precision integrating sound level meter performance specifications.
2. Procedures must meet ANSI S12.9 and other applicable ANSI standards.
3. Measurements must be made when ground level winds are 2m/s (4.5 mph) or less. Wind shear in the evening and night often results in low ground level wind speed and nominal operating wind speeds at wind turbine hub heights.
4. IEC 61400-11 procedures are not suitable for enforcement of these requirements except for the presence of tones.

Download “Simple guidelines for siting wind turbines to prevent health risks”

Entries of a noise log kept by a Brownsville family who live 3/4 mile east of South Byron in Fond Du Lac County, Wisconsin. The new wind turbines had just gone on line there.

Download “Brownsville noise log, March 3 to July 7, 2008″

Click here for updated diary through August 5, 2008.

Download “Turbine Layout Map, Brownsville, Wis.”