Electric Windmills. Hmmmm ...

[Arfa Daily]

[GB]

>> Arfa

"I?ve since heard dozens of similar stories from nurses, farmers, panel-beaters, civil servants, businessmen and forestry workers across the world, from New South Wales to Sweden and Pembrokeshire."

That simply proves how safe these wind turbines are. There must be tens of thousands of mills around the world, and yet the Daily Idiocy can only find a few dozen cases of people falling ill coincidentally when the mills were installed.

[Martin Brown]

is just the sort of hysterical panic reporting of hypochondriacs and malingerers that you expect from a clueless red top.

I reckon a fair number of these cases are self induced opposite of the placebo effect - though the symptoms are real enough.

Although I do have some sympathy for Jane Davies who for my money described fairly accurately the effect and sounds of being downwind and in the wrong position where wind shear induced touchdown of the spiral pressure wave from the blade tips occurs.

In every direction except downwind there is almost no audible noise.

I support Heaton-Harris in wanting to get a 2km set back on windfarms from significant habitation (especially in the prevailing wind downstream direction).

[The Natural Philosopher]

Most farms in other bigger countries are not near people.

Whenever they are problems occur.

Daily mail article is pants, but the problems are real enough.

[The Natural Philosopher]

If you bothered to READ the article, its the inaudible noise that is the problem.

That gets transmitted through the ground as much as the air.

In ANY direction. The wind shifts you know.

[Brian Gaff]

I wondered how long it would be before someone found a new ailment to blame on these things. Brian

[The Natural Philosopher]

Why, if they are so benign, do people bother to even look?

[Brian Gaff]

OK so are we saying that our current technology cannot make quiet wind turbines? The one mentioned is surely going to be on a smaller scale than some of the big farms. One issue about wind farms could be that the beat between turbines being slightly out of phase when heard at a distance could be a factor for sleep issues. Certainly a while ago problems were pinpointed in pumps for large gas mains which were creating vibrations inside houses, and this was i believe tackled successfully by the industry, so why not this? Brian

[The Natural Philosopher]

We can't make quiet aeroplanes, or quiet roads or railways either.

The one mentioned is surely going to be on a smaller scale than

Money.

Its almost impossible to create a wind turbine that doesn't get tip and blade vortices and these interfere with the poles giving a 3 per revolution thump They also interfere with any vertical wind shear there is.

And the lower the frequency the less it gets absorbed by the air, and the better it transmits through the ground.

You cannot solve fundamental problems with a technology by adding more technology.

Possible if you had them up 5000 feet in te air the infra-sound wouldbt carry. But you certainly wouldn't need a third runaway at heathrow..

I suppose you could make a soundproofed ducted fan assembly. Make them even more expensive than harry's solar panels.

They still wouldn#'t generate any useful electricity though.

[Graham.]

It's an ill wind &etc.

[The Natural Philosopher]

[Weatherlawyer]

The secret is in anisotropics.

Rail-road-beds are laid out in mathematically precise manners that seem purposed for the transmission of noise. for instance:

The sleepers are all set at the same distance so that when the passing locomotive drags down the air from just above it, it forms a tunnel that transmits sound escapement immediately behind it. This sound is construct out of the weight of the train and the distances in the roadbed that can form harmonics.

By extension then the same is true for roads.

They too are constructed with a lot of careful attention paid to installing acoustic harmonics. Widths of roads, depths of beds, spaces of lamp posts, white lines, heights of curbs etc.

Only in very few instances is attention paid to baffles.

The exact opposite is true in nature, where for instance, a tree is made of baffles a coppice takes on the shape of aerofoils and everything about them vchanges with the wind.

Know how.

Wind farms are still going through their genesis. It is rather like the motor car industry in the early 1920's and the steam revolution an hundred years earlier.

It isn't just money.

The biggest hindrance to the acceptability of wind farms is the noise. So solving the issue would resolve a lot of the other problems preventing investors getting a profit.

Since these things are based on aeronautical designs, it isn't surprising that architects and engineers designing them have paid little attention to baffling them.

When such blades are attached to aircraft they tend to get the aircraft out of the way of the problem. And the less wind resistance involved the faster they can do that.

The problems of vortice shedding are well known though and it is very likely that there are several universities already heavily funded by the industry to look for solutions.

It will probably turn out to be a matter of building a ring fence of some sort around the base of the tower.

Vertical wind sheer?

Do you mean the clear air turbulence associated with that? Because vertical wind shear at a plant would mean the turbine was not running.

Almost. You have fallen into the trap physicists the world over have fallen into ever since so called red shift was invented to explain the before and after effect first noticed with rail transport.

You have substituted condition for cause. (Nice linear thinking though.)

Quite. Take a look at the separate developments of the R100 and the R101 airships.

One architect just bunged any old thing on top of the initial problems and ended (literally ended) with a series of ever increasing problems.

The other just invented new physics.

That would be my first line of research. Wider channelling leading to smaller diameter blades of the sort used in jet engines.

The price of solar panels is set to fall dramatically as new chemistry takes on the problem of expensive rare earths. Already a university team has invented iron based (IIRC) photo-voltaic elements.

But the point is valid they only work on breezy days. They get switched off on stormy ones. I don't know when the off switch trips but I imagine it is before gales become strong gales.

However with ducting, the chimney effect comes into play. And add to that the ability to play with thermal induction by judicious painting of the tunnels.

Then there is the real estate supplied by the tunnels. They could fly adverts or they could house solar panels.

Not that the landscape would be improved. In fact everywhere would look like a Screwfix or Amazon warehouse. In fact nearly everywhere already does these days.

There used to be town centres when I was a lad. Then suburbs, then countryside.

Today there are used to be town centres but we still have suburbs.... Just inside the shopping centres that fence off our countryside from us all.

If you think I am being melodramatic, just go for a job interview at one of those neo-prisons.

[Frank Erskine]

I'm suffering from that...

Inter alia.

[charles]

most owners are companies whose directors live hundreds of miles away.

I've stayed ata farm house where there was a wind generator, horrible noisy thing - far worrse tahn the B road alongside which I live.

Why not?

[Tim Streater]

And visual impact, made a lot worse by peripheral vision flickering. So you have to look directly at the buggers in order to have least distraction.

[Grimly Curmudgeon]

stood just 300 yards from the Jackson family?s home."

300 yards? Neurotic cow.

[tony sayer]

In article , Grimly Curmudgeon scribeth thus

I had to work next to a wind farm the other week. Its not that noisy as such but it is, dunno quite how to put it, shall we say "Unsettling"

Bloody glad I don't have to live near one...

[<me9]

I went to one near here a couple of years ago. Standing underneath the beast there were frequent pings as the blades struck insects (it was the summer). Standing at the edge of the field it was in, about as far away from it as it was tall, the prominent noise was the wind in the nearby hedge.

We've a new one much nearer. I've only so far seen one operating, I don't think they have finished commissioning. I'll report on what it sounds like once it is running for real.

When they started erecting it, it looked *hugh*. Now (3 months later) it just blends in to the scenery. They are twice as tall as I thought they were to be, twice as high as the nearby powerline from the gas turbine power station.

[Dave Plowman (News)]

I slept in a caravan near enough underneath several of them last year for a couple of days. Some might say it explains things. ;-)

[The Natural Philosopher]

The infrasound gets worse inside a building

Its the sound you DONT hear that buggers you.