# Wind generators, are they noisey?



## 88724 (May 9, 2005)

Hi

Whilst away at the weekend I had the chance to sit a few feet (less then 4 foot away) from a wind generator Aerogen (I was sat on Harbour wall, the generator was on a pole on a rather nice little yatch)

Result *could not hear a thing even *when it got quite a spin on (I did get the windspeed from the owner of the yatch noted down on a pce of paper which I cannot find right now)


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## 88870 (May 10, 2005)

I think it depends on the wind generator and how it was mounted. 

A friend of mine had one before and had to switch it off at night .... and eventually got rid of it. It was that noisy. He tried everything to stop it humming - drove ya mad it did if you sat near it too long!


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## 88724 (May 9, 2005)

Hi Leigh

was it just the tune? or he didnt like humming at all?

Joking aside, it surprised me that it was silent, I expected to hear something, especially after all the comments I had heard before (similar to the story you related from friends (did you actually hear it yourself? its hard to tell from your post)


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## 88870 (May 10, 2005)

Hi George, it was definitely the tune .. a really aggravating whiiiirrrrrmm and yes I did hear it - just the once. That was enough.

Apparently it kept him and the houses nearby awake at night - I didn't camp near him when he had it on.

The owner of one of the fellows in the houses mentioned it and he had to agree that it was noisy. His bed was about 6 foot below it so he couldn't escape the whirring sound :lol: 

It just had to go. It wasn't a cheap one either. I think it may have been the balance that was wrong - fixings or something. It was set up exactly as it should have been though and the manufacturers said there would be some noise. 

I guess it is just a matter of how much you can stand. :? 

Did you get the make and model of the silent one? I am sure my friend would be really interested if you did.


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## kipperkid (May 16, 2005)

From what friends have said it depends on the design of the particular wind generator how much noise it makes, some are noisy, some aren't. Being totally not technical I know no more than that..........


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## 88724 (May 9, 2005)

Hi 

It said Aerogen, I was literally a few feet away and slightly down from where I was sitting. I could not hear a thing and I was straining to hear something


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## 88966 (May 11, 2005)

I can give a little information about wind generators having sailed with them for many years.

It depends largely on the size (output) as to the amount of external noise they make - usually very little except in a good strong blow (when they are often secured stopped anyway). The bigger problem is vibration, unless they are mounted very carefully on resilient mounts they can transmit vibration through the structure. I had one mounted above my bunk once that if the wind came up during the night it sounded like a Jumbo warming up.

The smaller output and more modern ones are much improved and are well worth considering - after all if they are a nuisance at night you can always tie them off.

Don't forget that the bigger the output the more wind it takes to start them turning.

The big advantage obviously is that on sunless days there is often a wind and it is available for longer than the sun anyway.


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## sallytrafic (Jan 17, 2006)

Several of these were on test at our depot. They were for offshore unmanned use so we were concerned with blade shedding/bearing failure not noise. We had a fenced exclusion zone around them (blade failure did occur in some cases) so didn't get that close to them but at a distance of around 5m in a force 5-6 you could clearly hear two components of sound the blade tip whistle which I would classify as very intrusive and a hum from the mounting resonating (this was fairly well damped and a stiffer structure than typical on a yacht). Mind you at that windspeed the fence made a racket too. More annoying to me was the noise from the flutter that occured when turbulent air hit the blades or when a gust came from a different direction and for a second or so the turbine twisted to seek out its direction. These turbines were being tested with a load matching system which tended to keep the load proportional to the power available so they were always under as much load as they could deliver. 

It was annoying to some in a doubleglazed office nearby (and next to mine) where the backgound noise of even a wild windy day was silenced but the tip whistle could still be heard by younger people rising and falling. Everyone had to stop talking and I had to listen carefully before my older ears could hear it though.

Staff not connected with the trial tended to grumble about the noise (and about the piece of wharf that was off limits). I talked to the union H&S rep about borrowing a noise meter but he concluded that the noise level was far below allowable limits so it would be a waste of time. 

I am not sure that we tested an aerogen in the depot because as far as I remember all our turbines had black blades, 

I guess George that this generator was at least partly sheltered from the wind and it was doing nothing like its max rpm otherwise self-preservation would have moved you further away.


A final thought if you thought predicting and matching solar to a battery system was difficult don't even consider wind. 

Regards Frank


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## 88724 (May 9, 2005)

Hi Frank

These modern Dooberies can be left out in a gale, the blades trim to stop it spinning to destruction. If the wind is that High I cant see the noise being bothersome (over and above the noise of the gale)


Matching, Wind at least does put some power out without breaking the bank and would probably be a good match with a Solar Panel (especially if you frequent coastal area's)


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## sallytrafic (Jan 17, 2006)

GeorgeTelford said:


> Hi Frank
> 
> These modern Dooberies can be left out in a gale, the blades trim to stop it spinning to destruction. If the wind is that High I cant see the noise being bothersome (over and above the noise of the gale)
> 
> Matching, Wind at least does put some power out without breaking the bank and would probably be a good match with a Solar Panel (especially if you frequent coastal area's)


I assure George that they cannot be relied upon to survive a gale (if by that you mean Force 8 or higher) and that trimming the blades is a option that works on larger turbines but doesn't reliably work on smaller ones. We spent a considerable time trying to work out why these items consistently failed when mounted on an unmanned location yet everybody said that they fitted and forgot them on Yachts.

Three things emerged

People lie
Some are removed or locked/tied down for the winter
A boat mounting moves with the wind ie the whole boat this (the theory goes) lowers the destructive forces at the top end of the range.

Of course I haven't had to use one for 18 months now but I've emailed a person who still is attempting this (backed by extensive and expensive R&D) and see if any of them survived this winter.

Regrards Frank


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## gromett (May 9, 2005)

http://www.unlimited-power.co.uk/Aerogen_wind_turbines.html
There are spec sheets here but none of them mention noise levels other than to say quiet. Unfortunately one mans quiet is anothers riot.

Karl


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## sallytrafic (Jan 17, 2006)

gromett said:


> .... Unfortunately one mans quiet is anothers riot.
> 
> Karl


Very true. Its sometime now since I studied the subject of noise with the OU but in making determinations of how much of a nuisance a noise is or will be you have to measure he ambient levels as well as the noise source. That means that even a loud noise like a pneumatic digger may not constitute a nuisance even though its absolute noise level my be dangerous, if for example, it was near the end of a Heathrow runway.

Therefore a 'quiet' wind turbine may not be noticed in a marina where rigging noise provides a high background level but in a rural camp site may cause a nuisance.

Regards Frank


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## 88724 (May 9, 2005)

Hi

Thats the one on the link you provided (Aerogen2), I can tell you by quiet they mean virtually silent, I could not hear a thing from a few feet away.


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## sallytrafic (Jan 17, 2006)

The only actual level so far that I can find openly published is "less than 35 dB(A) for a Swift". This has the feature that the blade tips are all joined together eliminating much of the blade tip noise. Apart from the shear and flutter noise caused by gusts arriving from other directions. 35dB(A) is a very low level and is unlikely to be heard over all but the quietest background but Silent it is not and I doubt that other small turbines get close to that figure.

There is also a problem with noise at what is known as breakaway speed. At that point there is a significant increase in noise and also the likelyhood of premature failure.

In case anyone should think I'm against wind power I am not its just that at the small sizes they can be so unreliable. Regrettably most of the data I have must be considered commercial-in-confidence so I can't share it with you.


Regards Frank


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## gromett (May 9, 2005)

I think the environment is just as important.
I have a building site opposite my house at the moment and the only noise I regularly hear is that of the beep-beep when the forklift is reversing.

They also have a generator running which I don't really notice when I am outside, but when I sit down to watch TV or go to bed it is the most annoying drone I have ever heard. The annoyance is only surpasssed when these little f*&^ing mini moto's go backwards and forwards outside my house :evil: :evil: 

I had considered a wind generator but decided against them for noise reasons. Instead I am going down the route of rewiring the van with a large battery bank and a big Victron inverter. Peace and quiet is what keeps me sane and getting away from the noise is sooo important now.

Cheers
Karl

Damn, just re-read this and I sound like a right grumpy meldrew.


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## sallytrafic (Jan 17, 2006)

sallytrafic said:


> GeorgeTelford said:
> 
> 
> > Hi Frank
> ...


Well I said I would report back with the results of last winter's trials and its a mixed message for George and me:

1. I was wrong  most (if not all) small offshore turbines survived last winter some considerable effort was made in mounting design to absorb or deflect gusts but the basic machines were unmodified.

2 I was right :grin: here is a quote "The only thing to think about if you fit them in a domestic situation is the noise of them when running full bore, they do tend to scream. Maybe OK for you if you fit them far enough away but the neighbours may get fed up with it."

Noise of course isn't an issue at unmanned offshore installations.

Regards frank


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## 88966 (May 11, 2005)

In the context of a motorhome IMO it is still the vibration factor that should be carefully evaluated - the vibration on a 'tin can'!!
I would like to thank Frank for his practical, technical feed-back


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## 88724 (May 9, 2005)

Hi Bill

Vibration ? I wonder why it doesnt bother yachties?


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## sallytrafic (Jan 17, 2006)

I guess from that comment you've never slept on board a yacht George. Unless extremely calm there is constant noise from rigging, fenders, pontoons other yachts and if you are unlucky parties etc and to a degree you get use to it. Also a day at sea is tiring and you tend to sleep soundly. I have slept through most things apart from dragging the anchor that tends to wake you up. All in all a motorcaravan is a much quieter beast. I flogged my boat to afford my second van.


Regards Frank


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## 88724 (May 9, 2005)

Hi Frank

That must be it then, I have slept in an APC's 4 Tonners, Land Rovers tearing across the coutryside of various foreign Lands.

Spell in the Army would do you all the world of good


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## 92046 (May 1, 2005)

*Wind gens*

Hi to all

I tested a number of wind generators including the Aerogen 50 watt, and the Aerogen 100 watt shortly after they came on the market some 25 years past, with the intension of installing offshore to run navigation lights, these were wind gens from 6 different companies, with the low cost unit being £85.00 up to £3500.00. for top unit !!! (1981 price)

4 out of the 6 companies wound up inside a year, the best company to deal with was the makers of the aerogen units,

After the first series of tests i sent them a list of recommendations, ie; to alter the blade design, alter the stator mounting, beef up the mounting bearing, beef up the brushes, beef up and re-secure the shaft bearing, they implemented all mods recomended and in 3 months sent up another 3 wind gens to re-test, these were tested up in the north sea on remote islands, with a recorded wind speed in excess of 80 MPH.

The only additional mods I had to carry out was to mount 2 x tail vanes back to back for extra strength, and to reduce the blade pitch, these 2 mods were due to the high wind at this location (Lat 60n +)

From the results of these tests I decided to install a number of 50 watt units, i can see (with binoculars) one of the 50 watt units running 2 x navigation lights while at this computer from the house.

The £3500.00 unit only lasted 5 months, the shaft broke.

As for noise, this all depends on the way it is mounted, and the wind speed.

For overall reliability and maintenance cost I chose to install solar panels wher possible on the navigation buoys, and remote lights, and sites with a heavy load wind gens and solar.

Best of luck to all

Colin


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## Rapide561 (Oct 1, 2005)

*Generator*

Hi

A few of the canal boats at Mirfield Marina have these little windmills on.

I have spoken to an owner and he tells me it is wired direct to the battery - hence just keeping the battery topped up. I had expected something quite different.

As for noise, I was stood about 10 feet away and it was a slight murmer, although not turning very fast.

He also has a gadget on to prevent "over charging"

Rapide561


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## teljoy (Jul 4, 2005)

*Re: Generator*

Hi

We were camped up near Newquay one year and were sitting in the van during the evening when I could feel a very gentle vibration through the floor. The conclusion I came to was that the wind farm a couple of miles away was the cause. Although when you got used to it was quite relaxing.

Terry


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## DABurleigh (May 9, 2005)

A good tip to avoid embarrassment is remove the batteries.

Dave


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## teljoy (Jul 4, 2005)

DABurleigh said:


> A good tip to avoid embarrassment is remove the batteries.
> 
> Dave


I hadn't thought of that!


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