Wind Power.

Problem?

Noise!

Hi Aris,

I've stood right below large wind turbines, and the sound they make is not very loud at all.

too funny.


I wonder what a pc fan company would do. (I should say would not do)

cars, they make noise too, going through the wind. I guess outer space is a quiet place.

I have even heard wind making wind make noise. amazing.

Low aerodynamic drag cars make very little wind noise!

http://neilblanchard.blogspot.com/2010/09/carben-ev-open-source-project-part-3.html

Some say it is not the human-audible component that is the problem.

Some research has delved into the sub-audio sound pressure generated by a massed array of multiple turbines. There is research that claims that multiple generators produce significant infrasound (below human hearing) at sound pressure that are bowel-trembling / nausea-inducing / psycho-drama triggering. Other research into infrasound has lead to explanations for the human perception of ... "ghosts".

So, it is not the human perceived audible level of noise. It is the sub-audio frequencies of sufficient amplitude that are claimed by some to produce physiological effects in animals, including the human kind.

A court case (in Australia) relied upon sub-audio measuring & analysing equipment to win the case for the plaintiffs, resulting in an out-of-court settlement.

However, there are interests on either side of this argument, and to-date, no solidly accepted consensus that the effects are real / repeatable, or, simply shysters out to make a quick buck. More work to be done here.

Now, regarding the electromagneteic radiation levels produced by mobile phones. There is research that suggests that brain cells .... [wink] [nudge]

Good night.

Not just noise, but the "weather" that can be affected as well.

http://www.bbc.co.uk/news/science-environment-11470261

Although I take all of this with a pinch of salt really, take for example the following.

Say we took an example field measured every possible thing about it before and after adding a number of huge wind turbines.

Then imagine what the differences would be if there was a forest instead of a field, or perhaps a housing estate instead of a field.

What kind of cretin believes that changing something wont "change" other environmental aspects as well, of course it will, the concern is how much it affects things, and how damaging this is, even then everything needs to be put into perspective and other possible outcomes considered.

The major possible problem for farmers is if it actually reduces the amound of crop that they can grow if they have wind turbines, if it is a fair difference, then they might think twice about having them, or get paid more by the utility companies. Either of these outcomes will affect the takeup of wind energy as it will put off farmers, or increase the price of wind energy, which is not good.


Andy

How does a wind turbine generate infrasonic sounds?

I think it is revealing that we are discussing such relatively innocuous effects -- no mercury, no fly ash, no carbon dioxide, no radioactivity, no poisons, no ozone, no cancer, no spills, no explosions, no collapses, no water contamination, no global climate change...

A report from a Canadian company is here:-

http://www.canwea.ca/images/uploads/File/CanWEA_Infrasound_Study_Final.pdf

Conclusion: Infrasounds (sub-audio) are present, but at safe levels

I've studied a lot of the medical literature and I have to say that I have not come across any studies that indicate there are any health consequences associated with being (living) near wind generators.

Anything that can cause air compression waves below 20Hz will do that. Now what exactly inside a wind turbine is doing that? I can't say. I do recall when I was super sensitive to it, now I'm more like ordinary deaf. (Crappy tradeoff)

Wind noise from a dragster with a straight exhaust? You're lucky to hear anything after that assault.

The article did mention, rightfully so, that noise you deem ok during the day, may come off as too noisy at night when trying to fall asleep. Think dripping faucet. Constant humming would be a particularly nasty nuisance.

I know that slamming a car door creates about a 5Hz sound. We can feel that.

I have stood *right* *below* a wind turbine, and it produced no such noises.

I have no doubts of what you're saying Neil, but I don't think those people were lying about their circumstances. Turbines can be huge, and where they are there are a lot of them.

The article stated that daytime noise was not a problem, only at night. Legal noise levels vary according to time of day.

Aris

They do make some noise, but it is hardly loud. Highways that are a lot farther away make a lot more noise that do wind turbines. I have also seen reports of people who claim they are being hurt by the "magnetic fields" from wind turbines... I think that this is mostly a NIMBY reaction, however.

Cape Wind looks like it finally start construction soon -- I hope we all look back on this in a few years and wonder why we didn't build wind turbines 10X faster.

There will be some issues, like compression issues with bats, but I think we can find solutions as we go along. We really need to take responsibility for our energy use.

Britain is set to generate more energy from offshore wind than the rest of the planet put together, after the opening of the world’s biggest ocean wind farm off Kent.
Nobody there to be bothered by the noise. Well, maybe a few fishermen.

The 1 Hz modulation of the broadband frequencies is still infrasound in some "ghostly" respect, as the amplitude modulation of a steady frequency signal from a radio tower is still a ghostly audible frequency.

Has anybody tried producing siding for a house that has power-generating pinwheels? You could put them on the 2nd floor and up.

Merge, please, the following two phrases together:

1) After thinking about it last night,
2) Much as I don't like to throw a damper on anything that might help free us from fossil fuels,

..... I am forced to conclude that the noise produced by windmills might be more detrimental than some might think.

The ear transmits electrical signals to the brain for infrasonic frequencies as much as it does for audible frequencies. You can therefore assume that the brain experiences as much excitation and it results in just as much stress. The only difference is that you can't listen to infrasonic frequencies -- each oscillation takes so long that you've forgotten the beginning of it before it reaches the end (humans can only aggregate sensory impressions for about 50 microseconds.)

According to the study, some of the windmill installations increased the ambient infrasound levels by about 20 dB compared to just the wind. That might not look like much, but remember that it represents 99% of the sounds' power.

I don't know about you, but I find windy days kind of creepy. Maybe it's the implied threat of the wind's force, or the sound of it hitting the trees, or maybe the ions it produces, or all of the above, or perhaps it could also be the unsettling effects of the infrasound. If that's so, I wouldn't want to increase it.

Most green technologies that I can think of produce less noise than their conventional counterparts. Maybe wind turbines should only be located quite far away from residential areas.

Again, I like the idea of little mini turbine pinwheels arrayed on the surface of buildings, if that's possible. Those can be imagined to produce nothing more than a sound similar to leaves.

Yeah, well, but they run day and night. Machine noise is a lot more apparent in the quiet of night.

Anyone's dreams of rural tranquility would be shattered by one of these. Is it worth it for the common good? I don't know.

Also, too, aren't these machines often built in arrays of multiples? Add 3 dB(A) for one additional and so forth.

If you compare this to having smokestacks, then I think it pales.

We really need to gain some more enlightened self-interest. NIMBY is a nearly universal reaction to anything new, but we are already living with far worse.

Highways are louder than wind turbines; and they have a significant detrimental health effect from all the air pollution, and they have oily runoff, too.

Oil refineries are nasty neighbors. And we all know how pristine oil production is, right?

Coal fired electricity power plants spew tons of mercury, soot, noxious and toxic fumes. The fly ash left over after burning coal is a massive problem -- the spill in Tennessee a couple of years ago is probably the largest industrial accident ever in the USA. It contains so many heavy metals, carcinogens, poisons, etc., it is staggering to think about.

Coal mining is a huge hazard; no matter what type. And there is a coal mine that has been burning underground in PA for about 40 years...

Natural gas production is getting worse and worse -- the so-called hydro-fracturing poisons well water, and makes it possible to have an explosive fire in your kitchen sink! The tailings from even exploratory gas wells can ruin the surrounding land.

So, I hope we can easily adjust to the sight and sound of wind turbines; considering all the pollution we can leave behind!

The last person I want to argue with is Neil -- he's far too well-intentioned and far too knowledgeable for one to have the heart to do so.

What does make me angry is when people object to the sight of wind turbines. Sorry to spoil your million-dollar view! -- you wouldn't mind if it were a lighthouse. These graceful objects have an intrinsic beauty. I remember 20 years ago when neighbors objected to neighbors installing those large satellite dish antennas in the yard. A simple, flower-shaped form made out of slender rods of metal. Meanwhile in the objecting neighbor's driveway is one or more two-ton wheeled conglomerations of dented sheet metal that sometimes make loud noise and spew out noxious fumes.

I just know from my experience living in the center of a small town that it's gotten louder and louder over the years with more and more machine noise. Now I can't even open my window on a summer night. Despite wind turbines being an alternative and green technology I fear that there will be -- like with everything else -- an inadequacy of regulation for the sake of the influential interests behind it. GE, who created the above chart, would be in that category. (I know that their products are in, like, every electric car, and it can be imagined that they're in the wind turbines, also.) There's gotta be places where they can be located that don't contribute to the noise pollution in residential areas, and there should be regulation to make sure of it. They'll be around after the smokestacks disappear.

I'm ignorant on this -- what's it like in the countries of northern Europe, who are usually more sensible in these matters than the U.S.?