But browsing EN3 I note it says:

2.7.58 Where the correct methodology has been followed and a wind farm is shown
to comply with ETSU-R-97 recommended noise limits, the IPC may conclude
that it will give little or no weight to adverse noise impacts from the operation
of the wind turbines.

So the IPC have a little room to manoeuvre as well.

I noticed that EN3 (2.7.60) says...

"There is no evidence that ground transmitted low frequency noise from wind turbines occurs at a sufficient level to be harmful to human health".

BUT strangely EN3 doesn't say the same thing about the health impact of airbourne low frequency noise. Why?

Posted By: CWatters"There is no evidence that ground transmitted low frequency noise from wind turbines occurs at a sufficient level to be harmful to human health".

maybe there had previously been some concern that ground-borne transmission accounted for either:
(a) how people could be affected at distances greater than supposedly possible
(b) why people could be affected by 'inaudible' frequencies (i.e. shaking the bed or somesuch)
so somebody was keen to eliminate those possibilities.

And this!

http://thegwpf.org/energy-news/5466-uk-energy-minister-vows-no-more-wind-farms-on-land.html

Ted - I was wondering about all those other turbines and how the accumulation issue was being brushed aside. Let's hope someone reads your submission!
Also, I though that our "local" structure plan had adopted a "no turbine within 1.5km of a dwelling" policy whatever that may mean.

Ted - So the Plaid Cymru leaflet through my door was overstating their achievements!
It'll be interesting to see how the 3 proposed wind farms are considered - The only real criticism levelled against the proliferation, that I've seen, was that the (different) developers had not co-ordinated or co-designed the accompanying grid infrastructure. Consequentially, there could be 3 new lines of pylons going to the same place or 2 consecutive upgrades to one new line. Madness, should be a condition that the developments are required to sought this before submitting any application, let alone all the other stuff!

windy, what did the PC leaflet claim?

One of the wind farms requires a 45km 132KV overground connection to a substation near Swansea. No one affected by that part of the development has any idea that it is even likely to happen yet nor exactly where the cables and pylons are going to go.

I also discovered yesterday that the owners of the existing wind-farm have objected to one of the new ones on the grounds that it will steal 'their' wind.

You really couldn't make this stuff up.

Some light reading on the experiences of local residents. http://www.senedd.assemblywales.org/documents/s6363/28%20February%202012.html

<blockquote><cite>Posted By: windy lamb</cite>Stealling wind- does that mean if I am immediately up wind of a wind farm they have to buy the wind off me -- didn't think so!</blockquote>

It's an interesting concept, but unlike light I don't believe that there is a legal "right to wind" (cue for hosts of smutty jokes.......).

It will be interesting to see what weight Appeal Inspectors put on minumum distances rules in local plans.

OK, the PC claim is correct as far as it goes.

The Carmarthenshire Deposit Local Development Plan does include a 1.5km setback condition for wind farms 25 MW and over - under policy RE1 - http://online.carmarthenshire.gov.uk/cccapps/ldpcarmdeposit/local_plan/text/Chapter_6.pdf

"proposals will not cause an unreasonable risk or nuisance to, and impact upon the amenities of, nearby residents or other members of the public and should be located a minimum of 1500metres away from the nearest residential property;"

Smaller installations are covered by policy RE2 which includes the same 1.5km condition!

But this LDP has not yet been through all the processes to become adopted yet - it may happen later this year. But I have asked for it to be included as a material planning consideration anyway.

Posted By: tedI also discovered yesterday that the owners of the existing wind-farm have objected to one of the new ones on the grounds that it will steal 'their' wind.

Posted By: windy lambStealing wind- does that mean if I am immediately up wind of a wind farm they have to buy the wind off me -- didn't think so!

The issue with 'stealing' wind is not one of theft - but an obstruction will give dirty wind to an area down wind (cue yet more smutty jokes). The turbulence created by turbine blades could cause inefficiencies or increased noise and other problems to a down wind turbine. A racing sailor will know the importance of clear wind and the advantage of clear wind is one of the reasons geese fly in V formation. Taking advantage of the wing tip vortex is another (so I am told).

Ted that link you put up: http://www.senedd.assemblywales.org/documents/s6363/28%20February%202012.html makes for depressing reading I have to say standing with one foot in the Wind Farm camp I found the comments made by residents both heartfelt and shocking in the way noise has blighted their lives, it appears that once the developers get a foot in the door you are always going to be fighting a rear guard containment action, not fair IMO. I watched Country File last weekend and there was a big piece on Wind Turbines and not a mention of noise as an issue it was all focused on visual impact and the planner they interviewed appeared to say that once you have a wind farm close by, by default you can expect more. It seems that noise and its impact should be given a far higher priority/publicity.

Has anyone come across any research on the effects that moisture levels in the air or low level cloud has on noise propagation? Noise levels do seem worse here when it is drizzling. Not sure if this is due to the moisture in the air acting as some sort of amplifier or the cloud base preventing the noise from dissipating.

We also get strange effects at times when the turbines are spinning quite quickly but there is absolutely zero wind where we are (tucked away up a cul-de-sac valley 3km from the wind-farm). The turbine noise is most noticeable then as there is no background noise of wind in the nearby trees at all.

Posted By: tedHas anyone come across any research on the effects that moisture levels in the air or low level cloud has on noise propagation? Noise levels do seem worse here when it is drizzling. Not sure if this is due to the moisture in the air acting as some sort of amplifier or the cloud base preventing the noise from dissipating.

Inversion layer perhaps?

http://en.wikipedia.org/wiki/Inversion_(meteorology)
http://en.wikipedia.org/wiki/Capping_inversion

Stops thermals, clouds and gliders from climbing. Can cause clouds to spread out forming a layer. Well known to cause music from pop concerts to travel further.

Wind can cause an inversion layer to break up (turbulent mixing) but not allways. Wind farm developers claim that stable inversion layers are rare and have even claimed that there is "no evidence stable inversion layers form" at particular sites. Glider pilots would dispute they are rare. In summer I've floated about just below an inversion layer in the horrible fug of polution that can form up there.

We also get strange effects at times when the turbines are spinning quite quickly but there is absolutely zero wind where we are (tucked away up a cul-de-sac valley 3km from the wind-farm). The turbine noise is most noticeable then as there is no background noise of wind in the nearby trees at all.

They are allowed to do that by ETSU-R-97. At "noisy" times they are allowed to increase background noise levels by a set amount. However at quiet times they are allowed to generate an absolute amount of noise. So relatively speaking they will be more noticable at times of low background noise.

Another possible cause is due to wind shear although that term is normally limited to variation in wind speed with height rather than horizontal spacing. In theory to protect against this effect wind farm developer monitor background noise levels at your house and correlate them with wind speeds and direction at the turbine. However they usually pick houses that are nearest to the wind farm not necessarily the one with the lowest background noise levels. It's not unknown for them to pick a house with a lot of trees nearby. Our planning authority no longer send the EHO to agree noise monitoring locations - so it's upto action groups to point out any problems with the locations choosen to monitor background noise levels at appeal. Their concerns are frequently ignored by appeal officers who say that any problems can be delt with after construction by a planning condition.

ETSU limits aren't hard legal limits either. It's not unusual for a wind farm to be approved even when forecasts show that noise limits will be exceeded for a percentage of the time.

Misty mornings and evenings on the coast of North Pembrokeshire you can hear the throb of the ferries coming into Fishguard several miles earlier than on clear mornings or evenings.