Resource Documents: U.K. (103 items)
Documents presented here are not the product of nor are they necessarily endorsed by National Wind Watch. These resource documents are provided to assist anyone wishing to research the issue of industrial wind power and the impacts of its development. The information should be evaluated by each reader to come to their own conclusions about the many areas of debate.
Author: Ward, Lyndsey
The sun always seemed to shine in Giggly Glen and the people were always smiling.
It was a very happy to place to live.
But then something happened that made the people very sad.
This is the tale of Tiny the Turbine who lived in Giggly Glen, on a pretty little farm that was rented by Mr Barley from the rich landowner, Sir Snatchit.
Tiny really was tiny. No-one could see or hear him. He had sat on the roof of the cowshed for many years and was completely hidden by the big trees of Giggly Glen Forest. Hardly anyone knew he was there.
Mr Barley used him in the winter to charge a little battery to light his cowshed where he kept his cows in the cold dark months. Tiny could just about do that but nothing else and spent the summer sunbathing and watching the wildlife all
around him. When the wind didn’t blow Mr Barley had to use a torch to tend his animals.
Mr Barley had a son, Ally. He was Tiny’s friend and would often go and talk to Tiny. Ally didn’t have many friends but Tiny was always there to listen when he had problems at school.
One day a wind developer called Mr McWeasel went to see Sir Snatchit.
He said because Sir Snatchit already had Tiny on his land he could get many more turbines, much much bigger ones. It would be called an extension and the man from the Government would say yes.
Mr McWeasel said if he could have permission to build the other turbines he could make Tiny much bigger and make him work harder and bring in lots more money from the Government. They would both be very rich.
He also said he would give the villagers a very small bit of that money the turbines made. It was the same money that the villagers had to pay to the Government in the first place. So really he was just giving the people their own money back. Mr McWeasel didn’t tell anyone that though.
Mr Barley didn’t want Tiny made bigger. Tiny did all he needed and didn’t bother anyone. The big turbines could be a problem for him and his family as they would be very close to their little house.
But because Sir Snatchit owned all the land and said yes to Mr McWeasel, the building of the turbines began.
Tiny was shocked when he saw Mr McWeasel’s men at work. They ripped up all the ground with big diggers, they cut down the trees in Giggly Glen Forest and poured big lorry loads of concrete all over the land. The wild animals ran away and the river turned a dirty brown colour and then … the birds stopped singing, the sun stopped shining and dark clouds spread across the sky.
Mr Barley went to see what was happening and sadly shook his head when he saw the mess and destruction made by Mr McWeasel’s men.
There were ten huge turbines. Each one taller than ten big trees standing on top of one another.
The biggest turbine was Trasher – Tiny’s very distant cousin – so named because he destroyed everything around him wherever he went.
Trasher was a bully. He was the ringleader of the other turbines. They laughed and jeered at Tiny because he was so tiny and rarely worked even though he did all Mr Barley wanted.
Mr McWeasel went to see Tiny. “You are too small. You don’t earn any money. I will order some parts and make you bigger and you will work harder for me.”
But then something else happened that really upset Tiny. His friends the birds were being hit by the blades of the big turbines. He told Mr McWeasel that he didn’t want to get any bigger and if he made him then he would refuse to work. He would go on strike and his blades would never move. He would not harm the birds.
Mr McWeasel was furious and ordered Tiny off Sir Snatchit’s land. “No-one disobeys me,” he said. Tiny looked to the other turbines for help but they just all stood and laughed at him.
“Go away,” shouted Trasher. “There is no place for someone like you here. You are not even big enough to boil a kettle! We need to earn money for Sir Snatchit and Mr McWeasel and if the birds get in the way then that is their hard luck.”
So Tiny left and was found by Ally, sitting crying on one of the trees cut down by Mr McWeasel’s men.
He listened to Tiny’s sadness about the birds and having to leave his home on the cowshed roof, just like Tiny had listened to him so many times when he had been sad.
Then he told Tiny what was happening to his family because of the turbines. He told him how his mother and father couldn’t sleep because of all the noise from Trasher and his friends. His father had crashed his tractor into the hen house the other day when he was so tired and had fallen asleep at the wheel.
Ally said he couldn’t sleep either and sometimes felt scared when he heard the thumping and swooshing of the turbine blades in the night.
It felt like the whole house was vibrating. The only time they got any peace from the awful noise was when the wind wasn’t blowing and the monster turbines weren’t turning. His mother often complained of headaches and never smiled any more. The chickens had stopped laying their eggs since the turbines came. Ross the sheep dog had starting hiding in the barn and wouldn’t come out and work the sheep.
Tiny jumped up! “This is not right,” he said. “We must stop it. Let’s go to the village and tell the people what is happening here.”
The village hall was crowded. People were shouting and angry.
“I can’t sleep and my visitors can’t sleep and now they won’t come back. How can I earn any money?” said Mrs Bumbly from Giggly Glen’s Guest House.
“My children can’t do their homework with that terrible din going on,” said Mr MacMillan from the bakery.
“The pupils can’t concentrate on their lessons any more with the never-ending noise,” said the Headmaster of the local school, Mr Knowall.
“My wife feels poorly all the time now. She says she has buzzing in her ears that never stops – not even when the turbines do,” said PC Doyle.
“I saw some bits break off one of the turbines – they flew a long way. They nearly hit me,” said Stan the Handyman.
“What if they caught fire?” asked the Fire Chief. “We couldn’t put a fire out so high up in the air.”
“My cat has left home and I have terrible headaches and feel ill every day,” said Mrs Miggins from the Post Office.
“I would sell my home and move away from Giggly Glen and those horrible turbines, but nobody will buy my house,” said Mr Donald.
“I saw the helicopter from the coastguard fly too close to the turbines when it was misty. There could be a nasty accident,” said Mr Foggarty.
“Enough is enough,” shouted Mr Barley. “We cannot live like this!
Mr McWeasel and his monsters cannot be allowed to ruin our lives and make us sick. Let’s send them away from Giggly Glen.”
“But how?” cried the villagers. “They are so big and frightening and dangerous for us to be near.”
Tiny turned to Ally and said, “Take the villagers to the turbines and I will meet you there.”
And so all the villagers, led by the now brave and confident Ally, marched up to Sir Snatchit’s land where they were met by Mr McWeasel standing in front of Trasher and the other turbines.
“We are here to tell you to go. You are making us ill. Living in Giggly Glen has become a nightmare since you arrived,” Ally shouted up to them.
“So what?” snarled Mr McWeasel. “What are you going to do about it, little boy?”
Trasher and the other turbines sneered and laughed at him.
The villagers were scared but then Ally pointed to the lane and yelled, “Look who’s with Tiny.”
There was Tiny sitting on top of his dear old friend Tuska the retired tank, chugging towards the turbines.
That was enough for Mr McWeasel. “Pack up lads we are off; we hated Giggly Glen anyway; not enough wind and not enough money.”
With that, Mr McWeasel, Trasher and his terrible friends were seen running off into the distance and as they did the clouds parted, the sun shone, the birds started singing and the deer and the rabbits came back. The hens started clucking as they looked for somewhere to lay their eggs and Ross the sheep dog came out from the barn wagging his tail.
Tiny looked around, smiled at all the happy villagers, winked at his little friend Ally and went back to the cowshed roof where he settled down for an afternoon snooze in the sunshine.
Peace and happiness had returned to Giggly Glen.
Written by Lyndsey Ward, with Cartoons by Josh
Download original document: “Tiny the Turbine”
Tiny the Turbine is available as a PDF to download and you may print for personal use or email as you wish and, if you like what we have done or wish to use it in your own campaigning, please make a donation on Josh’s website www.cartoonsbyjosh.co.uk/tiny-the-turbine to help fund this and possible future projects. All contributions, large or small, are gratefully accepted and appreciated.
See also: Subsidy Sam the Turbine
Author: Partington, Derek
This summary covers the principal findings of an analysis of electricity generation from all the UK wind turbines farms which are metered by National Grid, covering the period from January 2013 to December 2014.
The analysis shows:
- Monitored wind turbine output (as measured by the National Grid) increased from 5,894MW to 8,403MW over the period.
- The average capacity factor of all monitored wind turbines, onshore and offshore, across the whole of the UK, was 29.4% in 2013 and 28.8% in 2014.
- The monthly average capacity factor varied from 11.1% (June 2014) to 48.8% (February 2014).
- The time during which the wind turbines produced less than 10% of their rated capacity totalled 3,278 hours or 136.6 days over the two year period.
- The time during which the wind turbines produced less than 5% of their rated capacity totalled 1,172 hours or 48.8 days over the same period.
- Minimum wind turbine outputs averaged 132MW (1.8% of capacity) in 2013 and 174MW (2.1%) in 2014 as measured over 30 minute intervals.
- Variations in output of 75 to 1 have been observed in a single month.
- Maximum rise and fall in output over a one hour period was about 1000MW at the end of 2014 with a trend increase of about 250MW per year as measured over four years.
- There is no correlation between UK wind turbine output and total UK electricity demand, with output often falling as demand rises and vice-versa.
The conclusions to be drawn from the analysis are that the increase in nominal capacity:
- Does not increase the average wind turbine capacity factor.
- Does not reduce the periods of low (less than 10% of installed capacity) or very low (less than 5%) output.
- Does not reduce intermittency as measured by average monthly minimum output
- Does not reduce intermittency or variability as measured by maximum rise and fall in output over one hour period
- Does not indicate any possibility of closing any conventional, fossil-fuel power stations as there is no correlation between variations in output from wind turbines and demand on the Grid.
Therefore, based on the above, there is no case for a continued increase in the number of wind turbines connected to the Grid, or for the associated subsidies for wind energy, since this is an ineffective route to lower carbon dioxide emissions.
Download original document: “Intermittency of UK Wind Power Generation 2013 and 2014”
Author: Swinbanks, Malcolm; and Australia Senate Select Committee on Wind Turbines
Dr Swinbanks: Just briefly, I will review the submission that I made. I addressed four separate issues: first of all, the physical mechanisms for generating low-frequency sound and infrasound; secondly, the mechanisms by which people can perceive such infrasound; thirdly, I commented on the health effects and, in particular, two reports relating to these supposed health effects or the absence of them; and, finally, I gave an account of my own personal experience of adverse effects I have encountered when taking measurements near to a wind turbine installation.
If I could start off with the generation of infrasound, it is not often realised that NASA, in the early 1980s, actually carried out research on upwind rotor turbines. That is the modern configuration where the rotor is upwind of the supporting the tower, rather than downwind. Wind developers have often dismissed NASA’s work, saying it was not relevant because it related only to downwind turbines, but this is completely inaccurate. NASA had in fact identified the benefits of going to the upwind configuration at a very early stage. They also examined the effects of multiple turbines operating together and the effects of the separation between those turbines. They found that seven to 10 diameters separation was the ideal requirement for a turbine located downwind of its neighbours. But, in recent years, some wind developers have compromised on that spacing and have reduced it even to as little as three diameters in some cases, and that is asking for trouble, because the increased turbulence leads to increased low-frequency sound and infrasound.
The other effect that has to be considered is that as wind farm arrays are made larger and larger, the rate of attenuation as you move away from the wind farm is reduced. The result is that the setbacks from the boundaries have to be much greater to achieve the same reduction in sound. In recent years, people have stated that they have problems at distances of as much as three miles, and that is entirely consistent with the effects of increasing the size of the wind farms. Finally, I would point out that under conditions where the temperature profile is what is known as a temperature inversion, the low-frequency noise and what would I call the ‘silent thump’ of wind farms can carry over distances of three miles or more.
I would like to turn to how people perceive infrasound. The conventional method of hearing is through what are known as the inner hair cells of the cochlea. The effects of infrasound can be measured by a G-weighting scale, which is very similar to the A-weighting scale. It is effectively an extension of it, although the exact values do not correspond directly. Many people have evaluated whether or not the effects of infrasound are perceptible by simply comparing spectra with the hearing threshold and stating that the spectra are well below the threshold values and therefore the sound cannot possibly be perceived. That is not correct. At very low frequencies, it is the combination of different frequency components adding together which defines the total level of the infrasound, and that can be significantly greater than is observed simply by looking at the power spectrum.
People have reported having significant problems believed to be due to infrasound at distances from wind turbines. In that context, there are three different mechanisms which may be contributing to enhanced sensitivity. I have analysed a specific effect relating to the interaction with the threshold as a result of low and high frequencies being present simultaneously. In America, Dr Alec Salt has identified that the outer hair cells of the cochlea are actually much more sensitive at very low frequencies. He believes that there is some input to the nervous system resulting from them. Most recently, Paul Schomer, also in America, has considered the possible effects of sound pressure on the vestibular organs, which are the balance organs, and those effects could give the person on the receiving end a sensation of apparent motion, even though they are actually stationary.
I would like to make a further addition, which is just related to my own experience. Lying in bed, at a distance of three miles from a wind farm, my wife and I have on occasions been disturbed by the wind turbine noise. The most marked feature is that when you have gusts of wind, the turbine noise is masked by the gust and you get a huge sense of relief, only to find that when the wind subsides, the turbine noise returns and you again find yourself subject to the relentless sound.
The point is that when the wind gusts rise it is very much like the effect of when you come out of a tunnel into the light – a huge sense of relief. The sound levels of the turbines under those circumstances are probably less than the average sound levels of the wind, but nevertheless they are far more disturbing. This is noted also at higher frequencies, where people have identified that the annoyance from turbines at 35 dB(A) can be comparable to the annoyance of other more conventional sources at 55 dB(A). One commonly sees statements made that wind turbine noise is no different from any other noise, but the fact is it is different. It is clearly more perceptible at lower levels, and criteria relating to more conventional noise do not necessarily apply.
Turning to the health effects of wind turbines, there was an early report in 2009, which was an American Wind Energy Association funded report. This was the first time that experts had been brought together from both the medical profession and the acoustics profession. That report has been regarded as a definitive baseline report, and subsequent reports have tended to draw on it because of the qualifications of its authors. I consider that report to have been extremely biased. It failed to mention at all two of the most important aspects of wind turbine perception. Firstly, that in rural areas the hearing threshold is much reduced compared to the threshold when you are in urban areas and consequently you are much more sensitive to additional noise. Secondly, there is increasing sensitivity with continuing exposure. Some authors have described this a learned aversion. I have also experienced that at firsthand myself 30 years ago when working on natural gas compressor installations, which are effectively jet engines driving a compressor into an exhaust. In those circumstances, I found that over time, ultimately a period of two years, I had become very sensitive indeed to the low frequency noise and I could detect it under circumstances where previously I could not detect it at all.
That same health report misrepresented guidance which had been given in America by the Environmental Protection Agency as long ago as 1974 – that is 40 years ago – and they have failed to indicate that the presently permitted sound levels in the USA are too high and can lead to sleep disruption. The most recent health report that has been produced, again, funded by CanWEA, the Canadian Wind Energy Association, finally acknowledges the excessive permitted levels in the United States and the resultant consequences for sleep disturbance, but it does not highlight this. The statement is effectively buried in 25 pages of closely-spaced text. Now I believe a lot of the problems have been created as a result of that report and some of its successors, because it has completely understated the nature of the problem and has led, undoubtedly, to people being exposed to higher levels than they should be exposed to.
At the same time, it is common practice to place the burden of the effects of wind turbines onto the homeowners by stating that it is annoyance on the part of the homeowners and nocebo effects. By placing the burden on the homeowners, the apparent responsibility of the wind developer is reduced but, at the same time, this ignores completely the fact that the noise and, indeed, the infrasound can represent a significant intrusion into a rural home, particularly at night when people are trying to sleep. So I believe the correct terminology is to say that people suffer annoyance. It is something which is imposed on them.
I would also comment with respect to the nocebo effect that many communities welcomed wind turbines – this was particularly true of one island community in Vermont – but once the turbines started they discovered that there were some significant adverse effects. That is the very opposite of a nocebo effect. A nocebo effect is when there is prior anticipation of a problem, not when the problem is noted after the event. In that sense, I would like to make a brief comment that NASA, as long ago as 1982, presented a curve which showed the levels of infrasound that could cause adverse reactions by occupants. This showed that the levels of infrasound could be very much lower than the nominal threshold of hearing. People debate whether or not this is due to effects of vibration on a house structure – this is for people inside a house – or whether it is a true perception of infrasound; but that does not really matter. The fact is that, at octave levels as low as 60 decibels, which is a very low level for infrasound, there can be adverse reactions from occupants. That data goes back almost 35 years.
Finally, I would like to —
CHAIR: Excuse me, Dr Swinbanks —
Dr Swinbanks: comment briefly on my own personal experience of wind turbine health effects. I was asked by some friends of mine to help them measure the infrasound levels in the basement of their home at the wind farm at Ubly in Michigan. It is noteworthy that this particular wind farm had been designed in 2005, at which time Dr Nina Pierpont, a doctor in New York state, had been opposing that wind developer because of concerns she had relating to the likely noise environment of a wind farm. She has been roundly criticised all around the world for supposedly promoting scare stories. But in fact the wind farm that was developed at Ubly by exactly the same developer has proven to demonstrate all of the adverse effects that Dr Nina Pierpont warned about. Indeed, 10 families ultimately took legal action against that wind farm. The matter was settled out of court. But the important point is that I myself experienced directly many of the effects that Dr Nina Pierpont warned about, and she certainly was not making it up. The fact is that these effects can occur.
In my particular case, I was working on a very calm evening when wind turbines were operating but there was very little wind at ground level and you could not hear the turbines at all inside the house. I actually had to keep going outside to check that they were still running. After three hours in the house I began to feel ill and I found that I was lethargic and losing concentration, but it was not until sometime afterwards that I began to realise that it was the wind turbines that were likely to be responsible. The level of infrasound that I was measuring was a level that I considered to be very low and definitely not a problem. After five hours in the house I was only too glad to leave, and I thought, ‘At last I’m getting away from this,’ only to find that, when I started driving, my driving ability was completely compromised. The front of the car seemed to sway around as I consistently oversteered. I had lost coordination and I had difficulty judging speed and distance. When I arrived home, my wife observed immediately that I was ill; she could see that straight off. And it took me a further five hours to finally recover and for the effects to wear off.
The important point about that incident was that I had considered that the conditions – a nice calm evening at ground level, but with the turbines still running – were extremely benign, and I had wondered whether I would even get any results. So I certainly was not anxious about infrasound. Similarly, when I got —
CHAIR: Excuse me, Dr Swinbanks —
Dr Swinbanks: Yes?
CHAIR: We have got very short time. Would you mind if we go to questions now?
Dr Swinbanks: Yes, that is fine. In fact, I had effectively completed, so that is fine.
CHAIR: We will start with Senator Urquhart.
Senator URQUHART: Thanks, Dr Swinbanks. I picked up, I think, from your opening statement that you live near an operating wind farm – is that right?
Dr Swinbanks: Yes. We have a farmhouse in Michigan, and the county, Huron County, in which we live decided that they were going to install very large numbers of wind turbines. They installed a first set at two locations in the interior of the region where we are, and significant problems developed at one of those wind farms, but since then they have been installing progressively more wind turbines. We have an installation three miles south of us, which affects us only when the wind blows from a southerly direction and then only under certain weather conditions. But the intention is to install many times more turbines, and, essentially, the whole county will be covered in turbines if this situation continues as it is.
Senator URQUHART: Have you published any articles on infrasound from wind turbines in any peer-reviewed journals?
Dr Swinbanks: Not in peer-reviewed journals. I have presented, at conferences, the work that I have done, and it has represented a sequence of work. But I believed that it was better simply to get the information out into the public domain.
Senator URQUHART: In your submission you mention Steven Cooper’s study from the Cape Bridgewater wind farm. Do you believe this was a scientifically valid study equipped to make conclusions about the link between participant sensations and infrasound?
Dr Swinbanks: I believe that in a situation where people are reporting the effects that they observe while at the same time the operating characteristics of the wind farm are being monitored remotely, if you find that there is then a close correlation between those two situations, when they are well separated and there is no communication between the relevant parties, that does imply that there is a significant link and that people are reacting to real events.
Senator URQUHART: We heard from the Association of Australian Acoustical Consultants. They had done a small statistical analysis of Mr Cooper’s work. In this they found that Mr Cooper did not meet his hypothesis 63 per cent of the time. Do you think it is reasonable to suggest causality when a hypothesis is not meeting close to two-thirds of the event occurrences?
Dr Swinbanks: I would point out that I am not a statistician. I do not approach my own work from a statistical point of view. What I prefer to do is go and find out for myself what it is all about, and from my own experience I believe that what Steven Cooper has observed is entirely credible.
Senator URQUHART: Here in Australia we have had a population level study done that found no difference in the prescriptions that Australians had been given regardless of the distance that they lived from wind farms. Are you aware of any population level studies internationally that have found otherwise?
Dr Swinbanks: I am not aware of such studies. But I do know a lot of families whose life has been made pretty miserable by the wind turbines, and I find that every bit as impressive as the statistics that people collect. It is a characteristic of the medical profession that they operate hands-off and perform their evaluations entirely on a statistical basis. In the engineering profession, whenever possible we go and find out what it is like and subject ourselves to those conditions to gain an appreciation for ourselves. Sometimes I read documents from people who clearly have no direct experience. It is apparent from what they say. In this particular instance, occurrences are so comparatively rare amongst the general population that it is very easy to end up with a large number of negative responses and only a very small number of positive responses; yet the fact is that those positive responses can be directly associated with real problems.
Senator URQUHART: We are going to hear in a minute from Dr Leventhall. He has put forward in his submission that a much higher correlation in Mr Cooper’s work could be found between audible noise and sensations rather than infrasound and sensations. Do you agree with Dr Leventhall that the correlation that Mr Cooper found is statistically much higher with audible noise than infrasound?
Dr Swinbanks: There are both components of sound present. The definition of infrasound, according to Dr Leventhall himself, is that there is a very fuzzy boundary between infrasound and low-frequency noise. He has stated that that often causes confusion. In reports that he has written his definition of infrasound versus low-frequency sound, which is generally considered to be audible sound: he has defined 20 hertz on some occasions as being the boundary between the two effects and sometimes 16 hertz. In a different report he talked of 10 hertz to 200 hertz. Finally he even proposed 5 hertz to 200 hertz in a 2006 paper. So the point is that this definition of where you are between infrasound and audible noise is a very flexible definition. I do not consider that it is particularly important whether the noise is truly audible or just perceived as a sensation. The important effect is that people do detect something; they detect a sensation and can tell that something is happening. I learnt this 30 years ago when I was working on a gas turbine installation. Initially, I was very insensitive to the sound but, ultimately, I could drive up in my car and detect that the gas turbines were running even before the car engine had been turned off. There was a very marked increase in sensitivity. So I do not really think that it is important whether it is audible noise or inaudible noise that gives rise to the sensation. The fact is: people do experience real sensation, and these sensations can be very unpleasant.
Senator BACK: You mentioned size of wind farms. Were you referring to numbers of turbines or the actual physical size of the individual turbines, or both, when you made your comments in that regard?
Dr Swinbanks: I am referring primarily to the number of turbines. That is obviously related to the overall dimensions of the wind farm. But I have in mind, in particular, the Macarthur wind farm, which has very closely spaced turbines. It has a very large number – something in excess of 140. People are, I understand, experiencing adverse effects at distances of three miles. I believe that is a consequence of a large, closely spaced wind farm. Whether the effects would be as severe if the spacing of the turbines is made greater, I believe that would relieve some of the effects. But I think the main issue is the sheer number of turbines.
Senator BACK: You mentioned about what the 2009 American Wind Energy Association report had failed to take account of. You made the reference to increased sensitivity over time – increased exposure – and you gave an example of your own situation with gas turbines. One of the witnesses who has appeared before us, Dr Tonin, from this Association of Australian Acoustical Consultants, put to the committee that you could undertake this testing for infrasound using a pneumatic signal attached to hearing protectors effectively in a quiet room for a limited period of time. I think he mentioned 15 or 20 minutes. Could you comment on how much value you regard such testing would be in trying to come to terms with our situation?
Dr Swinbanks: My attention was drawn to that paper, and I have read it. I have two immediate comments. Firstly, he was attempting to distinguish whether symptoms were due to actual infrasound or due to nocebo effects. The important point is: there are two different outcomes which could distinguish between those effects, but, in fact, there are many more than two possible outcomes from the experiment. There are up to 16 outcomes of which only two are definitive outcomes relating to nocebo effects or infrasound effects. When I looked at the data, the most impressive correlation that I could see from the data was that the sheer action of putting on the headphones appeared to have increased the symptoms of the people being studied by at least 44 per cent. This was an experiment in which putting on the headphones had a measurable effect. I would argue that we do not yet know what exactly the mechanism causing people to suffer adverse effects. As I indicated, NASA, 30-odd years ago, had shown that people could experience adverse reactions at what are nominally very low levels of infrasound, but that was in houses where there was possibly vibration from the structures – and we do not know whether people are sensing anything through their body rather than their ears, because people often report in low-frequency noise or infrasound environments that they can feel —
Senator BACK: Can I stop you there. We need to get the answers fairly quickly so that all of us can have a go. You made reference to the circumstances of your own experience, where the wind was gusting and then was not gusting and the sound of the turbines with each. Some people have put to us the idea that an average sound or an average level is adequate. You in your paper have suggested that the use of an averaging technique may be missing cumulative pressure fluctuations and, in particular, peak pressure. Could you briefly explain that further and whether or not there is a value in averaged sound or averaged levels of infrasound decibels, please.
Dr Swinbanks: My immediate comment is that there is no value at all in an averaged level. In that example I gave, if you average it all, you find that the wind turbine level if anything would be less than the gusting level and you would then conclude that the wind turbines are not significant, whereas in fact it is very clear that they are significant. But the other important point is that there is a very well acknowledged paper that was written in 2004 by two authors, Moller and Pedersen, where they made it very clear that for the very low frequencies it is the actual shape and time history and peaks of the waveform that are important. In fact, Dr Leventhall, in an expert witness statement a couple of years ago, criticised me for supposedly not having read that report properly, but what I was doing was studying directly what the report recommended – namely, the time history and shape of the waveforms rather than long-term averaged versions of the waveforms.
Senator BACK: Thank you.
Senator LEYONHJELM: Dr Swinbanks, I have several questions. I hope we have time for them. Dr Leventhall was giving evidence in 2013 to a Vermont Senate hearing on the adverse health impacts of wind turbine operations in which he said they were ‘made-up, make-believe’, ‘hoo-hah’ and ‘a propaganda technique’. I understand he also dismissed some of your work on impulsive infrasound. Has he communicated those concerns to you?
Dr Swinbanks: He has not communicated the concerns directly. I have known Dr Leventhall for 40 years, but until very recently I had not seen him for 20 years. I was quite surprised, when I met him, that he appeared to have a very different perspective on the noise conditions in America from the perspective he gave at that Vermont meeting. When he was in the UK, he told me that he thought the sound levels in America were disgraceful. At the Vermont conversation, he attributed problems to ‘hysterical reaction’. The point is that permitted noise levels in the United States are significantly higher than in other countries and certainly higher than in Australia, so it is hardly surprising that there is what he called ‘hysterical reaction’. You would certainly expect that, if people are subjected to more adverse conditions, they are going to react and respond more strongly.
But it most certainly is not hoo-ha. I can say that from my own experience. There is no question that there are some significant effects. We do not know precisely what the mechanisms are. But people did not know what the mechanisms for seasickness were for many hundreds of years, and they still recognised the existence of seasickness.
Senator LEYONHJELM: In the NASA work in the 1980s, Kelley describes in detail the physical sensations resulting from infrasound. Are his descriptions consistent with what residents are now describing as the physical impacts of wind turbine sound?
Dr Swinbanks: Yes, I believe they are consistent. These symptoms have been known for a long time. Dr Leventhall says they are entirely consistent with his knowledge of low-frequency noise. He does not find it surprising, but he argues that it is not due to infrasound. As I have indicated, Dr Leventhall has even defined low-frequency noise as being from five hertz up to 200 hertz, which overlaps very substantially a region that most people tend to call infrasound. So we have a situation where, for frequencies around 12, 13 and 14 hertz, do you say, ‘That’s infrasound. That can’t be a problem,’ or do you say, ‘That’s low-frequency sound. The symptoms are perfectly understandable’? The fact is it is a very fuzzy distinction and you can place yourself either side of that boundary dependent on precisely how you choose to define the boundary. I believe that the symptoms are consistent. They are certainly consistent with low-frequency noise. It is a moot point whether or not people are subconsciously hearing something. They are aware of something. I have no doubts about the nature of the symptoms.
Senator LEYONHJELM: I just want to ask you a few technical questions. Your submission had some graphs that showed the pressure fluctuations and frequency. Mr Cooper’s report points out the need for narrowband measurements and not one-third octave bands for dB(A) or dB(G) when looking at infrasound and low frequency. Do you agree with that?
Dr Swinbanks: Certainly. I would not even dream of using one-third octaves or even averaging, over extended periods of time, just the pure spectrum levels. A proper analysis is both a narrowband frequency analysis coupled with a temporal analysis to look at the time history, as I commented earlier. If you go out to sea in a small boat, you do not worry about the spectrum of the waves; you worry about the shape of the next wave. This is what happens as you go down in lower and lower frequencies. For frequencies like 20 hertz and upwards, you tend to be more concerned with the blurring overall effect, but, as you get down to the very lowest frequencies, it is the shape of the individual waveforms that influences you. So one certainly should not be using these long-term averaging techniques.
Senator LEYONHJELM: Following up on from a question from Senator Back earlier in relation to peaks and averages, could you comment on whether or not it is possible to take a recording of infrasound or low-frequency sound – whatever you like – from a wind turbine and replicate it in a laboratory under controlled conditions in order to measure whether or not there is an adverse effect to it?
Dr Swinbanks: Yes, it is possible to do so, but the way in which people have been doing it so far, to me, seems a bit back to front. What they should be doing is, first of all, testing people who are known to be sensitive to wind turbines to try to find out what conditions enable an accurate replication of the effects. I do not see the point in just setting up an experiment in a laboratory and saying, ‘We didn’t observe anything’ if you have not first established, for a person who does suffer ill-effects, whether or not they actually respond to that test. There are real questions about what exactly are the important effects and what exactly should be reproduced in a laboratory. For example, I have quoted the NASA work of 30 years ago. People consider that, possibly, it was the vibration of the structures that people were sensing rather than the physical pressure variations of the infrasound. We do not know exactly what gives rise to the adverse effects. One has to validate any laboratory testing by being satisfied that people who are sensitive and have reported adverse effects can indeed experience those effects under the test conditions.
Senator CAMERON: Thank you for being here, Dr Swinbanks. You are three miles from the wind farm – is that correct?
Dr Swinbanks: That is correct.
Senator CAMERON: Was your house there before the wind farm was built?
Dr Swinbanks: Yes. I must make it clear that I am not directly complaining about those noise levels because at the moment the effects occur only when the wind is blowing from the south, which is only five per cent of the time. They only occur under circumstances of very severe temperature inversion. So it is a very occasional event. The point is simply that it can occur, and people who are in a position where they are encountering those sorts of conditions more frequently could also be expected to encounter such effects at such distances. The point that I am making is that such effects can be detected at these distances, not that those effects are a significant intrusion at the moment. But I would point out that in the future they are proposing to build turbines not just to the south of us, but to the west and the north-west, in which case those conditions may prevail for 35 or 40 per cent of the time. The fact is that modest numbers of turbines at sensible distances are not generally a consistent problem. Large wind farms operating under adverse circumstances can indeed be a significant problem at those sorts of distances.
Senator CAMERON: So when the turbines started to be built, was there an opposition group formed in your area?
Dr Swinbanks: There was never an opposition group as such, but there were a significant number of people who were making known their concerns. There was not a formal opposition group, but people were making known their concerns. The fact that there were two wind farms built at an early stage meant that people had some experience of what could be happening. The interesting feature was that you might say that those two wind farms, if you looked at them initially, looked pretty similar and pretty comparable; but one of them gave rise to very severe problems, while the other one did not appear to give rise to anything like as many complaints. The skill of constructing a good quiet wind farm is still pretty well lacking. It is very much a trial and error process, unless people obey sensible guidelines like ensuring that the separation between the turbines is of a sensible size and they are not choosing to mount turbines in locations, for example, on ridges where there can be a significantly distorted wind pattern and shear flow effects. The point is that there is a difference between a well constructed wind farm with sensible spacings and numbers and a poorly constructed wind farm.
Senator CAMERON: You also indicated that an inversion caused problems, and you gave evidence in relation to one night when it was not windy, and you had to keep going outside to check if the turbines were operating, then you became lethargic, you were losing concentration, you lost coordination when you were driving. Were you the only one in your household who had these symptoms?
Dr Swinbanks: It was not my household, it was the house belonging to some people who lived at the wind farm, who had asked me to take the measurements for them. Those people have experienced adverse effects to the extent that they actually had to rent alternative accommodation and go and sleep in the alternative accommodation at night. They initially tried to look at weather forecasts and decide if they could sleep in their own house or not, but they ultimately decided that the wind conditions could change during the night, and it could go from a benign night to a bad night. Therefore they began to sleep away from the property routinely and regularly. The particular point that I should like to make is that I was extremely surprised to experience these symptoms. I thought it was a non-event. But one particular point was that I was using a computer very extensively, and if there is a relation to motion sickness, I would certainly comment that if I am in a motor car and I try to use the computer or read – assuming I am not driving – I can very quickly become ill. I wondered whether this was purely conjecture, whether the fact that I was concentrating on using a computer actually enhanced the severity of the effects.
Senator CAMERON: Are you aware of the study that was done by Fiona Crichton, George Dodd, Gian Schmid, Greg Gamble, and Keith J. Petrie, titled ‘Can expectations produce symptoms from infrasound associated with wind turbines?’ It was a peer reviewed analysis reported in Health Psychology. They indicated that if there were high expectancy that you would get sick from infrasound then you would become sick. They did work with infrasound and sham infrasound, and it really did support the analysis that the psychogenesis and nocebo effect were real. Have you had a look at that?
Dr Swinbanks: Yes, I am familiar with that and I wrote a criticism of that document at the time. The point was that the difference between their sham infrasound and their real infrasound was essentially negligible. The real infrasound was at a level of 40 decibels, which is very low, and not surprisingly there was no difference in the response of any of the people between the sham and the actual infrasound. The other point is that the duration was only 10 minutes. In the effects that I described it took five hours for the full effects to become apparent.
I have related that whole situation to sea sickness. It used to be the case, in the 1970s, when I did a lot of sailing, that one would frequently encounter people who considered that seasickness was just psychological. Very often, they learned the hard way that it is not. But the point is that, if you wanted to test two groups of people for seasickness, you would not put two separate groups into two separate boats and put them on a flat, calm lake for 10 minutes and then announce that any reactions prove that seasickness was caused by a nocebo effect. That would actually be regarded as a joke. So I am afraid that I consider that that particular experiment was more an experiment in a pretty obvious psychology than anything relating to the validity of whether infrasound represents a real problem or not.
Senator CAMERON: So many questions, so little time. Thank you.
CHAIR: Dr Swinbanks, is the sound pressure level important when considering biological effects of infrasound and low frequencies, or could it be the frequency via acoustic resonance?
Dr Swinbanks: I think I should make it clear that I am not a biology specialist, so anything I say is amateur in that context. But I believe that the long exposure times can be a factor in inducing effects in people. Again, drawing a parallel with seasickness, it was not uncommon to go to sea for eight, 12 or even 24 hours and think, well, you are not going to get seasick this time, only to discover suddenly at the end that you do in fact start to succumb. In that context you can find that the onset of the symptoms can seem to be very rapid, even although you have been exposed for a long duration. So I think there are important considerations relating to duration of exposure.
I point out briefly that Dr Alec Salt, who is an expert on the characteristics of the cochlea, has suggested there is a phenomenon known as temporary endolymphatic hydrops, which is a progressive swelling and blockage of the little pressure relief hole at the end of the cochlea. If that becomes blocked then you can become very much more sensitive to infrasound. So it is quite possible to hypothesise that long-duration exposure is causing a blockage to progressively develop, and when it becomes severe then the person will start to experience much more extreme effects from the sound pressure than they would if there were no blockage.
So you could imagine in those circumstances that there might be a protracted period where there was no effect and then a comparatively rapid onset of effects. It would then take time after the exposure for those effects to clear, so you would then have persistence for some time afterwards. This is a whole area that requires a great deal more study. One of the conclusions, though, of the original 2009 AWEA report was that there was no need for any further research. I would completely disagree with that. I think it is apparent that people are now taking the issue seriously and at last people are beginning to investigate more thoroughly exactly what may be happening.
CHAIR: From what you have told me, I take it that the level of sound pressure is less important?
Dr Swinbanks: There are several factors that are important and when they come together they can effectively reinforce one another. I am not certain that you can take out one specific component and reject the rest. It is a combination of different contributions that can ultimately lead to the end condition. But the obvious conditions are length of exposure, sound pressure levels but also the frequency and the nature and character of the time history of the wave forms.
CHAIR: Thank you. We are running over time. If there are no further questions —
Senator BACK: I have one, but it will have to go on notice.
CHAIR: Dr Swinbanks, there may be further questions placed on notice by senators. We would appreciate it if you accept those and respond.
Dr Swinbanks: Certainly.
CHAIR: Thank you for your appearance before the committee.
Dr Swinbanks: Thank you for giving me the opportunity to speak. I am very grateful for that.
CHAIR: Thank you.
—SWINBANKS, Dr Malcolm Alexander, Private capacity
Monday, 23 June 2015, Canberra
(Evidence was taken via teleconference)
Author: Northern Ireland Assembly Committee for the Environment
This report sets out the key conclusions and recommendations of the Committee for the Environment on its inquiry into wind energy, and the evidence considered by the Committee which led to those conclusions.
The terms of reference for the inquiry were:
- To assess the adequacy of PPS18 and related supplementary guidance in regulating proposals for wind turbines on a consistent and strategic basis, with due regard for emerging technologies and independent environmental impact assessment;
- To compare the perceived impact of wind turbine noise and separation distances with other jurisdictions and other forms of renewable energy development; and
- To review the extent of engagement by wind energy providers with local communities and to ascertain how this engagement may best be promoted. …
Key conclusions and recommendations
The Committee came to the following conclusions and recommendations after due consideration of the evidence before it.
The first term of reference relates primarily to the adequacy, or otherwise, of Planning Policy Statement 18 (PPS 18). The current policy is set out in PPS 18, with a slightly different approach proposed in the draft Single Strategic Planning Policy (i) to remove the significant weighting of wider environmental, economic and social benefits considerations, and (ii) to urge a cautious approach to the siting of turbines in Areas of Outstanding Natural Beauty (AONBs) or other designated landscapes. …
The Committee found that many submissions to the inquiry focused on perceived inadequacies of current planning procedures. Members expressed concerns that there may not be adequate consideration of the cumulative impact of turbines, but they recognised that balancing individual applications against cumulative effect is a wider issue across planning. The Committee recommends that procedures should be put in place so that a saturation point is clearly defined, rather than being a judgement call of individual planning officials.
The Committee considered the present situation in Northern Ireland where local councils have to devote finite resources to the investigation of noise complaints made against wind turbines. This contrasts with other areas of the UK where the developer is required to undertake investigation of any complaints and to demonstrate compliance with noise limits. The Committee therefore recommends that the standard conditions which were developed by the Institute of Acoustics, and which have been endorsed in Scotland, England and Wales, should be routinely attached to planning consents in Northern Ireland. …
Wind turbine noise and separation distance
The second term of reference of the inquiry focuses on wind turbine noise and separation distances from dwellings. This has been the most emotive aspect of the inquiry as many submissions detail the adverse impact perceived noise from wind turbines is having on the respondents’ day to day lives. From the evidence put before the Committee, it seems apparent that current guidelines in respect of permissible levels of noise are no longer adequate and that the research evidence available has increased significantly since 1997. The Committee therefore recommends that the Department should review the use of the ETSU-97 guidelines on an urgent basis, with a view to adopting more modern and robust guidance for measurement of wind turbine noise, with particular reference to current guidelines from the World Health Organisation.
The Committee was also concerned that there does not appear to be continuous long-term monitoring of noise from wind farms, either by developers or by the relevant public sector organisations. If such information were available it would introduce an objective measure of the noise output of turbines, as opposed to the projected noise impact produced by a desk-top exercise as part of the application process. This would provide both developers and planners with factual evidence and a useful assessment measure for future applications. The Committee recommends that the Department should bear responsibility for ensuring that arrangements be put in place for on-going long-term monitoring of wind turbine noise.
Following on from this, the Committee has heard evidence from local residents who are concerned about potentially harmful low-frequency noise emitting from wind turbines. The Committee is not in a position to determine the scientific basis for such information, but members believe that it warrants further investigation. The Committee therefore recommends that the Department, working with local universities, should commission independent research to measure and determine the impact of low-frequency noise on those residents living in close proximity to individual turbines and wind farms in Northern Ireland.
The Committee is aware that PPS 18 advises that a separation (or setback) distance of 500m, or 10 times rotor diameter, will generally apply to the siting of wind developments, but there is no indication given in the policy whether this is in relation to noise or to visual amenity. The Committee’s specialist advisor has indicted that, due to local topography, linear distance is less important than the robust actual measurement of noise, but it is obviously very relevant to the aspect of visual amenity. There are no generally agreed separation distances in other jurisdictions and the lack of prescription has given rise to a great deal of criticism from respondents.
The Committee has considered whether the current degree of flexibility should continue to be available to planners in assessing applications, but agreed instead that a minimum setback distance should now be determined by the Department. The Committee recommends that the Department, taking into account constraints on the availability and suitability of land for the generation of wind energy, should specify a minimum separation distance between wind turbines and dwellings. …
The final term of reference for the inquiry relates to the extent of engagement by wind energy providers with local communities and the promotion of such engagement. The Committee found that, although the wind industry is aware of the vital importance of engagement and is moving towards a more robust standardised approach (as exemplified by the recent publication of the NIRIG Community Best Practice Guidance 2014), many residents still feel marginalised in the whole process of siting wind developments near their homes.
The Committee believes that the views of the community must be given consideration by both planners and developers. Community concerns regarding visual amenity, noise and health, and the impact on house prices, are often not given due regard; and community groups trying to investigate or object to applications find the process resource-intensive and not transparent. This should not be seen as a mere box-ticking exercise – the views of residents need to be listened to, considered and, if possible, changes made to take account of these views. It is not just about preparing reports: there is a need to act on the findings.
The Committee believes that there should be timely and early engagement with communities. It recommends that the use of a community engagement toolkit should be made mandatory, as a useful measure of independence, and the list of statutory consultees should be widened to reflect all users of the countryside. …
The possible devaluation of homes, where wind developments have been sited in close proximity to existing dwellings, has been a contentious issue. While the Committee has been presented with emerging and contradictory research evidence on this, it believes that a scattered rural population – both those who have lived in the area for generations and those who have chosen to live in quiet scenic locations – has some cause for grievance. The Committee therefore recommends that the developer gives consideration to providing compensation where there is clear and compelling evidence of a significant drop in house value directly relating to the siting of a wind development. …
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