It kills me that the argument in WV often centers around the "scenic impairment" caused by windfarms, when future coal projects will continue to use hilltopping methods -- where you just remove the top of a mountain to get at the coal underneath.
Though I suppose the conundrum there is that a decrease in demand for coal-based electricity in WV wouldn't result in a decrease in demand for their coal, so that with wind farms you'd get the hilltopping
and some ridgelines full of turbines.
Some thoughts on some of the environmental concerns (from the site linked above):
Quote: Noise pollution from the turbines is a concern frequently downplayed by the industry, but it is a problem for those who live in the surrounding area, as was noted in the Wisconsin study.
I've read a bit on this, and it definitely seems to me that both the those who want to install wind and various NIMBY groups who oppose it overstate the issue one way or the other to support their own cause (no great surprise there). More careful modeling of noise transmission patterns in installation could go a long way toward remedying the problem. The industry tends to use a simplistic distance:noise relationship in addressing the concern -- such and such a turbine at such and such a distance generates this much noise. Problem is, they're working on a flawed model, and features of the landscape and of varying wind at different elevations can result in much greater noise downwind of the turbine in certain circumstances. Conversely, wind opponents take particular instances of noise being a nuisance and try to paint any potential installation with the same brush. I think there need to be some scientifically-based regulations concerning noise and wind installations. Currently there are none.
Quote: Broken blades, ice throws and collapsing towers present a safety concern for the people, homes, businesses and roads in the surrounding areas.
Some stuff on ice throws from something I've written (first draft) but have not revisited or epanded upon or fixed (that is, it's only slightly less crappy than my regular A2K posts:
To set the stage, it may be appropriate at this point to quote the AWEA's own FAQ page on the potential hazards to human life posed by wind energy (
http://www.awea.org/faq/tutorial/wwt_environment.html):
It has been estimated by a number of reliable sources that 50,000 Americans a year die from air pollution, of which about one-third is produced by power plants. By contrast, in 20 years of operation, the wind industry (which emits no pollutants) has recorded only one death of a member of the public--a German skydiver who parachuted off-course into an operating wind plant.
A concern that is commonly voiced by opponents of "backyard" wind generators is the potentially lethal hazard posed by ice being thrown from the blades of a spinning turbine. Such arguments frequently rely on equations that assume that ice is shed as the blade rotates at operating or even maximum speed, a scenario that is highly unlikely for two reasons:
Most newer turbines are equipped with sensors that shut down the turbine when ice accumulates on the nacelle.
Even when such sensors fail - usually because heat generated within the nacelle thaws surface ice more rapidly than out on the rotor - the likelihood of the rotor being able to operate at anything approaching operating speed is much reduced. (
http://www.awea.org/faq/sagrillo/ms_ice_0306.html)
Thus, most ice that is shed from a turbine is not thrown but falls. Ice may pose a pose a risk to people situated directly below or just downwind of the turbine, but such a risk is no different than that of ice falling from any other tall structure. A required "setback" distance (generally enacted to minimize perception of noise from a turbine) should be adequate to ensure that there is no risk to the general public from flying or falling ice.
As far as anecdotal evidence of the potential for ice throw from wind turbines in cold climates, the Final Environmental Impact Statement of the proposed Forward Energy wind energy project in southeast Wisconsin (prepared by the Wisconsin Public Service Commission and Department of Natural Resources) has this to say:
No ice throw from turbines has ever been documented in Minnesota where hundreds of wind turbines have been installed in recent years. The only documented incident of ice damage was to a truck parked at the base of a wind machine.
For more information on the effect of icing on rotor speed, go to
http://www.awea.org/faq/sagrillo/ms_ice_0306.html.
For a study of the likelihood of ice throws at varying distances from a turbine in areas of ice accretion, go to
http://www.vtt.fi/virtual/arcticwind/boreasiv/assessment_of_safety.pdf.
Quote: Bird deaths and interference with migration patterns for birds who live in and migrate through the area, including several endangered species, has led the U.S. Fish and Wildlife Service to publish their own studies about the negative ecologically effects of wind farms.
That's the USFWS's job. The red herring here is to look at the damage to wildlife populations from, say, a coal fired plant or a hydroelectric project and compare them to damage from a wind project. The worst-case scenario in terms of bird death to date has been at the Altamont Pass wind resource area in northern California, where there has been significant mortality among raptor populations since turbines were erected in the 1970s. Here, there have been notably large quantities of raptors (esp. golden eagles, I believe), and raptor populations have declined (but have not been decimated) since the inception of the project. It is uncertain just how much of an effect the extensive development of the surrounding area (particularly the rapid expansion of the neighboring city of Livermore) have had on the local raptor populations. Nonetheless, Altamont is a particularly high-use location for birds, and as turbines are replaced they are being sited using data collected from a detailed study of raptor use patterns in the area. Hopefully this will reduce the level of bird mortality in the area in future years.
Sadly, such care isn't being taken in new installations, such as the Forward Energy wind project near the Horicon Marsh in southeastern Wisconsin. It's a major throughway for dozens of migrating bird species -- one of the most important in North America, and the project is siting turbines as close as 1.2 miles away from the marsh. At least we'll get some good hard data about the effects of wind on birds out of it...
Nonetheless, the mortality inflicte by any wind project pales in comparison to the level of mortality from other anthropogenic sources -- feral cats, for instance, or transmission towers, which have in the past been implicated in single night bird kills numbering in the 10,000s. (The birds don't hit the towers themselves, which they can see, but rather the guy wires supporting the towers, which they apparently are unable to detect.)
Here are the USFWS interim guidelines, if anyone's interested:
Quote:Site Development Recommendations
The following recommendations apply to locating turbines and associated structures within WRAs selected for development of wind energy facilities:
1. Avoid placing turbines in documented locations of any species of wildlife, fish, or plant protected under the Federal Endangered Species Act.
2. Avoid locating turbines in known local bird migration pathways or in areas where birds are highly concentrated, unless mortality risk is low (e.g., birds present rarely enter the rotor-swept area). Examples of high concentration areas for birds are wetlands, State or Federal refuges, private duck clubs, staging areas, rookeries, leks, roosts, riparian areas along streams, and landfills. Avoid known daily movement flyways (e.g., between roosting and feeding areas) and areas with a high incidence of fog, mist, low cloud ceilings, and low visibility.
3. Avoid placing turbines near known bat hibernation, breeding, and maternity/nursery colonies, in migration corridors, or in flight paths between colonies and feeding areas.
4. Configure turbine locations to avoid areas or features of the landscape known to attract raptors (hawks, falcons, eagles, owls). For example, Golden Eagles, hawks, and falcons use cliff/rim edges extensively; setbacks from these edges may reduce mortality. Other examples include not locating turbines in a dip or pass in a ridge, or in or near prairie dog colonies.
5. Configure turbine arrays to avoid potential avian mortality where feasible. For example, group turbines rather than spreading them widely, and orient rows of turbines parallel to known bird movements, thereby decreasing the potential for bird strikes. Implement appropriate storm water management practices that do not create attractions for birds, and maintain contiguous habitat for area-sensitive species (e.g., Sage Grouse).
6. Avoid fragmenting large, contiguous tracts of wildlife habitat. Where practical, place turbines on lands already altered or cultivated, and away from areas of intact and healthy native habitats. If not practical, select fragmented or degraded habitats over relatively intact areas.
7. Avoid placing turbines in habitat known to be occupied by prairie grouse or other species that exhibit extreme avoidance of vertical features and/or structural habitat fragmentation. In known prairie grouse habitat, avoid placing turbines within 5 miles of known leks (communal pair formation grounds).
8. Minimize roads, fences, and other infrastructure. All infrastructure should be capable of withstanding periodic burning of vegetation, as natural fires or controlled burns are necessary for maintaining most prairie habitats.
9. Develop a habitat restoration plan for the proposed site that avoids or minimizes negative impacts on vulnerable wildlife while maintaining or enhancing habitat values for other species. For example, avoid attracting high densities of prey animals (rodents, rabbits, etc.) used by raptors.
10. Reduce availability of carrion by practicing responsible animal husbandry (removing carcasses, fencing out cattle, etc.) to avoid attracting Golden Eagles and other raptors.
Turbine Design and Operation Recommendations
1. Use tubular supports with pointed tops rather than lattice supports to minimize bird perching and nesting opportunities. Avoid placing external ladders and platforms on tubular towers to minimize perching and nesting. Avoid use of guy wires for turbine or meteorological tower supports. All existing guy wires should be marked with recommended bird deterrent devices (Avian Power Line Interaction Committee 1994).
2. Is taller turbines (top of the rotor-swept area is >199 feet above ground level) require lights for aviation safety, the minimum amount of pilot warning and obstruction avoidance lighting specified by the Federal Aviation Administration (FAA) should be used (FEE 2000). Unless otherwise requested by the FAA, only white strobe lights should be used at night, and these should be the minimum number, minimum intensity, and minimum number of flashes per minute (longest duration between flashes) allowable by the FAA. Solid red or pulsating red incandescent lights should not be used, as they appear to attract night-migrating birds at a much higher rate than white strobe lights.
3. Where the height of the rotor-swept area produces a high risk for wildlife, adjust tower height where feasible to reduce the risk of strikes.
4. Where feasible, place electric power lines underground or on the surface as insulated, shielded wire to avoid electrocution of birds. Use recommendations of the Avian Power Line Interaction Committee (1994, 1996) for any required above-ground lines, transformers, or conductors.
5. High seasonal concentrations of birds may cause problems in some areas. If, however, power generation is critical in these areas, an average of three years monitoring data (e.g., acoustic, radar, infrared, or observational) should be collected and used to determine peak use dates for specific sites. Where feasible, turbines should be shut down during periods when birds are highly concentrated at those sites.
6. When upgrading or retrofitting turbines, follow the above guidelines as closely as possible. If studies indicate high mortality at specific older turbines, retrofitting or relocating is highly recommended.
Quote: Strobe effects created by the turning blades have been another concern for those who live near the wind farms.
Some stuff on "strobe effects" (the more common term in the literature is "shadow flicker") -- FEIS is the Final Environmental Impact Statement prepared for the Horicon Marsh project in WI, available at
http://psc.wi.gov/utilityinfo/electric/cases/forwardWind/volume1Feis.htm (there's a lot of it):
Shadow flicker
Forward FEIS finds that almost the entire area that may experience 25 hours of shadow flicker per year is within 1000 feet of the turbine. The maximum turbine height at the site is 398 feet. There's a good picture on p. 183 of the FEIS about this, though I can't for the life of me figure out how you could get shadow flicker south of the turbine in the northern hemisphere. At any rate, the greatest exposure to shadow flicker is to the east and west of the turbine, there is some to the north (where shadows are shorter), and there is none directly south. If the predominant wind direction is from the north or south, then, it would seem that the potential for shadow flicker is minimized even further. Even within the range that will experience flicker (but still towards its edge), a particular location may only get flicker at certain times of year, because of the changing sun angle between solstices.
Regardless of the angle of the sun and the potential shadow cast by the turbine, flicker should be imperceptible at a distance of 10 rotor diameters (
http://www.dti.gov.uk/renewables/renew_3.5.1.4.htm). While this may be as great a distance as 800 meters on a utility-scale wind farm, for a home-sized turbine, this distance may be less than a hundred meters. In fact, the distance of risk could be even less than this, since the distance at which shadow is perceptible is a function of the width of the rotor blade, which is obviously smaller on a smaller machine.
Health effects associated with shadow flicker
Flicker can be a nuisance at frequencies greater than 2.5 Hz (
http://www.dti.gov.uk/renewables/renew_3.5.1.4.htm) and flicker may induce seizure in a significant percentage of photosensitive epileptics at frequencies as low as 4 Hz (
http://web508.gsfc.nasa.gov/developing/checklist/flicker_guidelines.cfm). For current-generation large-scale wind machines, which have a maximum flicker rate of about one second (
http://www.dti.gov.uk/renewables/renew_3.5.1.4.htm), this is not an issue. For smaller and/or older machines with rotors that spin more quickly, this may be a consideration. However, the distance over which flicker is an issue is much less for these machines, as noted above.
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