Mynydd Llansadwrn Action Group

Help Protect our Welsh Mountain Landscapes


Mynydd Llansadwrn

What the politicians say

Latest News

Wind Turbine Facts

Renewable Energy

Energy Conservation

The Action Group


Facts about Wind Power

Wind turbines may be noisy and intrusive, but supporters of wind power claim that turbines are an efficient, non-polluting and cheap source of electricity. But are they?

A new report (September 2009) by the Danish Centre for Political Studies is an in-depth analysis which depicts the truthful situation of wind in Denmark. Click here to download the report in PDF format (2.73MB).

It is not good news for proponents of the wind industry like David Milborrow, UK renewable energy consultant. He recently wrote “ . . .....western Denmark, where wind farms generate 26 percent of national electricity consumption, . . . . “ (latest issue (162 EN3) of the  the Institution of Civil Engineers’ Energy journal). Denmark does not generate 26% of its national electricity consumption from wind as claimed  by Milborrow. Denmark generates 19% of its electricity from wind and its average national consumption of wind energy over the past five years has been a mere 9.7 percent !!!

Professor Michael J. Trebilcock of the University of Toronto writes an interesting article (April 2009) in Canada’s Financial Post, entitled "Wind Power is a Complete Disaster". As he correctly points out, windpower in other countries (Denmark, Germany) has not reduced CO2 emissions nor closed any coal powered plants. In fact, emssions have gone up and new coal plants have gone online. His comments reflect a professional career studying economic regulation, including a year as Research Director of the Ontario Government's Electricity Market Design Committee (1998). 

Click here to download of copy of the article in MS Word format and to link to the original click editorial  piece with comments.

For an excellent general introduction to the science of wind turbines, read the article from 2006 by J.A. Halkema, a retired Dutch electrical engineer with a long experience of electrical generating, switching and testing equipment. Click here to download a copy of his article in Adobe format (939KB)

Here are some facts about wind turbines under the following headings:

  1. Energy output
  2. Wind turbines and global warming
  3. Wind turbines in the landscape
  4. Environmental damage
  5. Noise pollution
  6. Health issues
  7. Light pollution
  8. Threat to wildlife and livestock
  9. Jobs and tourism
  10. House prices
  11. The economics of wind power
  12. Radar interference

The figures given here are based on the evidence available at the time of publication. References are given at the foot of this page.

1. Energy output

Energy produced by wind turbines varies from zero to 87% of their rated capacity, depending on the wind. If the wind speed is less than about 4 metre per second (9 miles per hour), no electricity; if the wind speed is greater than about 25 metre per second (56 miles per hour), turbines are shut down for safety reasons. The British Wind Energy Association (BWEA), the lobbying body for wind power developers, claims that wind turbines have a load factor of 30% of their rated megawatt (MW) capacity. 

According to the Department of Trade and Industry (DTI), the average load factor for onshore wind turbines in the UK in 2003 was 24.1%. Ofgem quotes the following average load factors for Wales:

2003 - 23%, 2005 - 25.0%, 2006 - 27.4%, 2007 - 26.1%, 2008 - 30.6%

Output curve for a typical 2.5 MW wind turbine. Note that "full" output is only reached when the wind speed is 15m/s (34 miles per hour or Beaufort Force 7) 

A report published in 2006 by ABS, an independent energy market research company, (see ref. 1) highlights new authoritative evidence from other countries in Europe that shows how wind power actually works, as opposed to what is being claimed. Here are some of the key findings cited in their report:

·        There is a mismatch of supply and demand. During periods of high pressure weather systems that bring cold winters and hot summers, wind speeds are at low levels but demand is at its highest. In other words, when demand is highest, wind power makes its minimum contribution.

·        Each country mentioned in the ABS report has experienced extreme difficulties in balancing the grid. (see also ref 2 and 3) During times of maximum feed-in from wind turbines, regional grids become heavily overloaded. Germany has found that it will need a further 2,700 km of costly high voltage transmission lines to accommodate its new wind capacity built in remote areas.

·        Wind power capacity in Germany is expected to reach 48 gigawatt  (1GW= 1000MW) by 2020; however, this wind energy is so intermittent and unreliable that it is equivalent to only 2 GW of stable fossil fuel capacity.

·        In Denmark, during 2004, wind accounted for 20% of total electricity production but supplied only 6% of consumption. This happened because wind farms produced a surplus at periods of lowest demand. Denmark exported 84% of its wind-generated electricity to Norway, at a financial loss. The Norwegian electricity system uses carbon-free hydro power, so the effect of CO2 emission reduction from Danish wind farms was nullified. (see also ref 3)

The output from wind turbines, besides being weather dependent and therefore unreliable and unpredictable, is extremely low in comparison to conventional power stations. 

The average UK consumption is about 40,000 MW. The government target is to increase supply from renewables from the current 1% to 10% (i.e. 4,000 MW) by 2010. To meet this target through wind power, we would need to install an additional 8,000 modern 2-MW turbines (with 0.5 MW realised output, assuming 25% load factor) over the next 4 years - that is 2,000 wind turbines to be installed each year, or approximately 8 every working day, year in year out. Even if this were technically feasible, it would not reduce our dependence on fossil fuels or nuclear energy because wind turbines, being weather dependent, need backup from traditional power stations.

 Because of the variability of wind power, back-up fossil fuel plants must be operated at low load to maintain system reliability. Evidence shows that switching base load fossil fuel plants on and off to balance a system produces higher carbon emissions than continuous operation. So the backup required for wind is a higher than expected source of emissions (see ref 4).

Quoting E.On's own website:

"The force of the wind generally fluctuates considerably within the space of a few days and even a few hours. Sometimes the wind can drop just when the demand for electricity is at its peak. The graph, which documents the amount of electricity generated during the month of November in 2001, illustrates this point well.

"The graph clearly shows that wind energy on its own is not capable of providing a reliable supply of electricity. Coal-and gas-fired power stations are required to smooth out the fluctuations in wind power output and need to be ramped up and down constantly as wind power output fluctuates. This shortens their service life and causes them to consume more fuel-in much the same way as a car in city traffic. The higher specific fuel consumption produces higher emission levels, thereby negating some of the environmental benefit of wind power."

At least this developer is honest about the disadvantages of wind power! The website goes on to state that:

"Since wind energy on its own is not capable of delivering a reliable supply of electricity it can never be a substitute for large, centralized power stations. Current wind-energy subsidies are so high that wind turbines are now also being built in unsuitable locations."  

In 2009, The Kentish Weald Action Group (KWAG) has prepared a new article "Onshore wind turbines : the myth, the reality and the bottom line" that challenges much of the information provided by the wind industry. Their conclusion, based on previously unpublished research, is that during a typical UK winter (2008-2009) turbine output in Britain will seldom rise above 10% of installed capacity meaning virtually all the energy from onshore wind turbines will have to be backed up.

To read the article click here

E.On has claimed (August 2008) that wind energy is so unreliable that even if 13,000 turbines are built to meet EU renewable energy targets, they could be relied on to provide only 7 per cent of the country's peak winter electricity demand. E.On has argued that, during the coldest days of winter, so little wind blows in the UK that 92 per cent of installed wind capacity would have to be backed up by traditional power stations.

It argues this would require new coal-fired power stations to be built so they could be used in an emergency when little wind blows. This, E.On suggests, will mean that, to meet renewable targets of 20 per cent of energy being provided from renewables by 2020, the UK's installed power base will need to rise from 76 GW today to more than 100GW. The company estimates this could cost £100 billion.

2. Wind turbines and global warming

Wind turbines are being promoted by both the UK government and Welsh Assembly as an effective strategy to reduce greenhouse gas emissions and thereby counteract global warming trends. However, estimates of the contribution of wind power to a reduction in CO2 emissions are generally exaggerated.

To date it has been assumed as self evident that wind generated electricity will save carbon. However recent studies by Dr. Sarah Myhill show there is very little evidence that this is the case and indeed mounting evidence that wind generated power is not carbon friendly. Current available figures (January 2009) bring her to conclude that during its lifetime one 3MW turbine built on a peat site will “save” 6,356 tonnes of carbon and “cost” somewhere between 27,213 and 40,773 tonnes of carbon.

Click here to download Dr. Myhill's paper, see ref 23.

The BWEA assumes that wind will replace coal-fired capacity unit for unit and bases its calculation for emission savings on this assumption. The BWEA figures are used to support developers’ claims in their planning applications for wind farms. The developers of the Blaengwen wind farm claim a carbon dioxide offset figure of 0.85 tonnes per MWh, based on the assumption that "…the electricity generated by wind turbines effectively replaces the output of coal-fired power stations, unit for unit." (see ref 5).

When wind-generated electricity is introduced into the grid system, it cannot be said with any certainly which type of electricity source it is replacing. It could be replacing coal, or gas, or even an emission-free source such as hydroelectricity or nuclear power. According to DTI’s Wind Energy Fact Sheet (see ref 6): "The UK electricity market is extremely complex …and it is not possible to make categorical statements on how wind changes the generation mix."

Therefore, it is more accurate to use a ‘grid average’ to reflect the uncertainty as to the type of power, i.e. coal, gas, nuclear, etc, that is displaced when wind power supplies energy to the national system. Both the DTI and the Carbon Trust use a ‘grid average’ figure of 43 tonnes of carbon dioxide emissions per year when calculating potential emissions savings. This factor of 0.43 tonnes per MWh is about half that claimed by the BWEA and wind farm developers (see above). After 2010, the DTI expects that the generation mix will have changed and that wind power will be operating in conjunction with Combined Cycle Gas Turbines (CCGT). Therefore, post 2010, emissions savings from wind turbines should reflect CCGT displacement, which at 0.27 millions tonnes per MWh is even less than the emission savings figures currently accepted by the DTI and the Carbon Trust.

The estimated emission savings from wind turbines must be balanced against the emissions from the fossil-fuelled spinning reserve required to balance supply and demand when wind power is brought into the grid system. (see ref 7)

Quoting from a study commissioned by the Renewable Energy Foundation in 2004:

[Reserve] capacity is placed under particular strains when working in this supporting role because it is being used to balance a reasonably predictable but fluctuating demand with a variable and largely unpredictable output from wind turbines. Consequently, operating fossil capacity in this mode generates more CO2 per kWh generated than if operating normally…Thus the CO2 saving from the use of wind in the UK is probably much less than assumed by Government advisors, who correctly believe that wind could displace some capacity and save some CO2 , but have not acknowledged the emissions impact of matching both demand and wind output simultaneously. As a result, current policy appears to have been framed as if CO2 emissions savings are guaranteed by the introduction of wind-power, and that wind power has not concomitant difficulties or costs. This is not the case. (see ref 4)

The amount of CO2 emissions a wind turbine can save is a matter of conjecture since there are no mechanisms in place to take accurate measurements. However, Denmark, the country with the most wind-generated electricity per capita, has shown no reduction in its overall CO2 emissions; in fact, Denmark’s CO2 emissions are rising. (see ref 8)

Electricity generated by wind turbines is emission-free at the point of generation, and to this extent it does not contribute to global warming. However, there are many emissions and pollutants associated with turbine manufacture and delivery and in the construction of the wind farm site with its access roads, grid connections, substations, etc. Each turbine foundation requires between 500 and 1,000 tonnes of concrete and aggregate; concrete manufacture is one of the largest sources (about 7%) of man-made CO2 emissions. All these industrial processes contribute to global warming.

Many wind farms are being proposed on Forestry Commission land. Building a wind farm on forested land involves chopping down vast areas of trees, which, if left standing, would absorb CO2. Wind turbines, unlike trees, do not remove CO2 from the atmosphere. According to the Environment Agency, one acre of coniferous trees absorbs 3.5 tonnes of CO2 each year. However, when trees are clear felled, the decomposition of vegetation that is left behind actually adds to the CO2 emissions problem. At the Cefn Croes wind farm site, not only were acres of forest clear felled, but deep ancient peat bogs were also stripped off and drained, releasing stored CO2 and methane into the atmosphere. (see Cefn Croes photo-gallery) As the peat gradually dries out, it will continue to oxidise and release even more CO2.

Electricity generation accounts for only one-third of our CO2 emissions, the bulk comes from aircraft, vehicle exhaust, domestic heating and industrial processes. According to DTI estimates, reaching the 2010 renewable energy targets would achieve a reduction of about 2 million tonnes of CO2 per year. Even if this were achievable, it is not impressive when viewed in relation to national and global emission rates. A 2-million-tonne reduction of CO2 is a mere 1.7% of total UK emissions (550 million tonnes) and 0.0004% of world emissions (24,000 million tonnes). Global emissions are expected to rise by 2% a year, mainly from China and India. Wind turbines can have no significant effect in reversing, or even slowing down, these global warming trends.

3. Wind turbines in the landscape

Even wind-energy enthusiasts have to admit that these giant machines are out of keeping with the landscape. They are built on high-altitude, prominent sites to catch the wind, marring some of the most scenic mountainous regions of Wales. 

To improve output, turbines are becoming bigger (see diagram below). The turbines being proposed for the Welsh hills are usually about 400 feet tall (120 metres), about three times the height of a typical electricity pylon, with a bladespan greater than the wingspan of a jumbo jet. Our remote and beautiful landscapes are further degraded by hundreds of miles of pylons and transmission lines needed to transport the electricity to the grid system and on to more populated parts of the UK. The visual intrusion of these structures contravene local development plans.

The diagram below gives an idea of scale - the vertical scale is in metres (one metre equals 3.3 feet). 

But remember, turbines are sited on high hills and mountain ridges to take advantage of the prevailing winds, so their visual intrusion is magnified by their prominence in the landscape.  

The largest wind turbine now is the Enercon E-126 (198 metres high) and rotor diameter of 126 metres. It's rated output is 6-7 MW, shown in the diagram below (see ref 9 for a description of the construction of a 5MW machine).

Spanish-owned Gamesa, based in Newport, have revealed plans for 14 wind turbines in the Upper Afan Valley. This proposal under the "working title" Llynfi Renewable Energy Park, is to consist of four, 603ft turbines on Ynyscorrwg and ten, 603ft turbines on the Gelli Mountain, near Croeserw. These turbines would be by far the largest yet proposed for the UK, well over four times the height of Swansea's Big Wheel.

If all the proposed wind farm developments go ahead, turbines will be visible from almost anywhere in Wales.  

With acknowledgements to "Visit Wales Now" website


4. Environmental Damage

Turbine construction will inevitably affect the local environment, probably destroying wildlife habitats. Building access roads, crane pads, and concrete foundations, felling trees and draining peat bogs change the soil composition at the wind farm site. The result is faster run-off of water during heavy rainfall with the associated risk of flooding in the lowlands. Once the rural uplands have been degraded by turbine construction and access roads, there is the danger that the area will be opened to further erosion through vehicle traffic and the pressure for further development.

Wind farm construction can disrupt the hydrology of the area and contaminate water supplies. At Ovenden Moor wind farm a 200-foot turbine cracked the bedrock and diverted the natural watercourse. Excavation of cable trenches caused peat to dry out, and tracks to the turbines formed pools of foetid water that could not drain away (see ref 10)

The developers of the Blaengwen wind farm admitted in their Environmental Statement (see ref 5) that ‘the proposed turbines, crane pads and tracks have the potential to disrupt the hydrology regime of the site’; nevertheless, they did not feel it necessary, nor did the planners insist, that they undertake a hydrology study of the area. The site is drained by several watercourses and there are a number of private water supplies within a few miles of the site. Yet there has been no investigation into the potential effects that this construction project, which will involve blasting or drilling into the bedrock to build the turbine foundations, may have on the hydrology of the area and the water supplies of nearby properties. It is hard to imagine what other major construction project would be allowed to proceed with so little regard for the inevitable consequences for the local environment.

Peatlands are vitally important on a worldwide scale.

" The Ramsar Convention recognises that peatlands are a habitat that is generally overlooked, misunderstood, under-recorded, and yet which represents more than 50% of the world’s terrestrial wetland, and which holds around 25% of the global pool of soil carbon. The world’s peatlands contain more than three times the amount of carbon than is stored in the world’s tropical rainforests. The carbon in peat is stored for thousands of years .." (see ref 11)

During the construction of a wind farm at Derrybrien , Ireland, in October 2003, there was a bog slide. Here is an extract from the report on this incident:

"The whole rationale for constructing wind farms is that they reduce CO2 outputs by providing energy at a much lower rate of CO2 release than energy produced by fossil fuels. In most parts of the landscape, the CO2 outputs from wind farms are associated only with original construction of the components, and then vehicular emissions linked to development of the wind farm site and subsequent turbine maintenance. Peatlands are the one part of the landscape where wind farm construction results in significant additional and ongoing CO2 release. This is because peatlands represent substantial long-term stores of carbon which is released if they are disturbed.…

It is thus difficult to understand the logic of disturbing and releasing such long-term carbon stores in order to install devices whose whole purpose is to reduce carbon emissions. If wind farms are to be built, it is surely sensible to avoid using a habitat which, as a result of the wind farm, will release CO2 into the atmosphere throughout the life of that wind farm." (see ref 11)

More information about this bog slide can be obtained from The Scottish Wind Assessment Project

There are currently about 1,200 wind turbines at 84 sites in the UK supplying less that 0.3% of our electricity needs. Those 1,200 turbines save a mere 0.09% of our carbon dioxide emissions - the bulk of emissions comes from aircraft, vehicle exhaust, domestic heating and industrial processes.

The government has plans to expand Britain's airports. Jetliner emissions are injected straight into the upper atmosphere and are therefore three times more damaging in their warming effects than emissions from cars, homes and industries. Air travel is the fastest growing source of carbon dioxide emissions; aircraft emissions are expected to double by 2030, rising from 5% to 30% of the UK contribution to global warming.

The developing world is increasing its output of carbon dioxide emissions every three or four months by the same amount the government hopes to save in ten years, mainly through wind energy. The government is helping China to install coal-fired electricity generators, which will contribute to carbon dioxide emissions.

5. Noise pollution

Noise of the mechanical gearing system is similar to that of a motorcycle and this can be quietened to a limited extent. But the low-frequency, penetrating sound of the rotating blades is more troublesome. It has been compared to the low thud of base notes from loud music, or the sound of a helicopter at a distance. So far there has been no success in reducing this noise, which can continue unabated day and night for extended periods and can travel several miles. There are recognised health problems such as pulse irregularity and sleep disturbance associated with this type of low-frequency sound, which is sometimes below the normal audible limit.

In assessing the suitability of a site, wind-energy developers measure the audible range of noise, but never the infrasound - the low-frequency noise - which is sometimes below audible limits. Developers do not generally acknowledge wind turbines do produce low-frequency noise and vibrations, and they assume there will be no noise problems for residents living more than 500 metres away from a wind farm. At a recent wind farm planning hearing in New Zealand, residents living up to three kilometres from a wind farm described how their lives were disturbed by turbine noise and vibrations, sometimes for several days on end. (see ref 12)

In South Cumbria, local residents, having suffered four years of noise disturbance from turbines, have initiated court action against the developers and the local Council in an attempt to resolve the issue of noise nuisance. This is after pre-construction assurances from the developers that the design and control systems would ensure there would be no noise nuisance. (See

Research done in the Netherlands (see ref.13) at an installation of 17 wind turbines on the German/Dutch border has shown that the noise level is far higher than predicted by the developers, particularly at night. The developer's predictions were made based on wind speeds measured at 10 metres from the ground, but at night the wind speed at the height of the turbine hubs (98m) is frequently much greater. A group of turbines produce pulses of sound which cause greater effect when they synchronise. "The sound then resembles distant pile-driving or as a resident said: an endless train".

Another study into low-frequency noise concluded that:

 "… the levels of both ground-borne and air-borne sound which cause disturbance are lower in amplitude than originally thought to be troublesome or to be detectable by people."

 The report went on to say that because of rising levels of low-frequency sound, 

" it is not unreasonable to speculate that in future a greater proportion of the population will be troubled." (see ref 14)

Articles in the Daily Mail on March 10, and The Daily Telegraph on April 16, 2007, describe the suffering of Mr and Mrs Davis living in the noisy shadow of a wind farm in Lincolnshire.  Click here to download the Daily Mail article. Mrs Davis also appears on a short video - click here for the link to the Youtube site.

In 2007 a report was published by Barbara J Frey and Peter J Hadden on "Noise radiation from wind turbines installed near homes: effects on health" (see ref 22). This report includes an annotated review of the research and related issues, as well as comments from some of the families affected by wind turbines.

The review concludes that a safe buffer zone of at least 2km should exist between family dwellings and industrial wind turbines of up to 2MW installed capacity, with greater separation for a wind turbine greater than 2MW installed capacity.

Click here to download a copy of the report in Adobe format (pdf file, 986KB).

6. Health issues

It was reported in July, 2009, that the number of people in Ontario, Canada, reporting adverse health affects due to wind turbines continues to rise. The new total is now 86 which is an additional 33 new victims. This is a disturbing 62% increase from 53 as reported in the first WCO (Wind Concerns Ontario) community-based self reporting survey earlier this year, made public on April 22, 2009. To download the full July press release in MS Word format, click here.

Dr Nina Pierpont has done substantial research on these health issues and written a new book on the subject of health hazards from the vibrations of wind turbines, referred to elsewhere on this site as vibro-acoustic disease. Click here for more details, and to download a pre-publication copy of Dr. Pierpont's new book on the subject from her website, click here (the copy is in Adobe Acrobat format - 2.85MB).

Wind Turbine Syndrome is the clinical name she has given to the constellation of symptoms experienced by many (though not all) people who find themselves living near industrial wind turbines: sleep problems (insomnia), headaches, dizziness, unsteadiness, nausea, exhaustion, anxiety, anger, irritability, depression, memory loss, eye problems, problems with concentration and learning, tinnitus (ringing in the ears).

  As industrial wind-plants proliferate close to people’s homes and anywhere else people regularly congregate (schools, nursing homes, places of business, etc.), Wind Turbine Syndrome likely will become an industrial plague.

Research in Portugal published in May, 2007, also demonstrates that wind turbines in the proximity of residential areas produce acoustical environments that can lead to the development of  "Vibro-Acoustic Disease" in nearby home-dwellers. Go to our 2007 news page for more details.

Other medical studies indicate that onshore wind farms can be a health hazard to people living nearby because of the low-frequency noise. Low-frequency noise travels further than audible noise; it is ground borne and felt through vibrations, which can resonate with the human body. For some people there is no effect, but for others it can be very disturbing. According to a report by Dr Geoff Leventhall, a fellow of the Institute of Physics and Institute of Acoustics, 'Low-frequency noise causes extreme distress to a number of people who are sensitive to its effects.'

Research by Dr Amanda Harry showed that all but one of the 14 people living near the Bears Down wind farm in Cornwall had experienced increased incidents of headaches, and 10 said they had problems sleeping and suffered from anxiety. According to Dr Harry, a local GP in the area, there was a range of reported symptoms from headaches, migraines, nausea, dizziness, palpitations and tinnitus to sleep disorders, stress anxiety and depression.

Dr Bridget Osborne, a doctor in Moel Maelogan, north Wales, where three turbines were erected in 2002, has presented a paper to the Royal College of General Practitioners in which she reported a marked increase of depression suffered by local people.

The Danish government has stopped erecting onshore turbines because of the health problems associated with noise.

SHWAG (Seamer and Hilton Wind-farm Action Group) an action group in the northeast of England near Middlesborough published a report in January 2009 describing many of the risks to the general public from wind turbines including noise, light flicker and the growing number of accidents worldwide involving giant turbines catching fire, shedding blades or parts of blades and throwing large ice lumps.

Click here to download a copy of their report in MS Word format.

7. Light pollution

The strobe effect when sun is behind the rotating blades can, according to medical opinion, cause dizziness, headaches and trigger seizures. Shadow flicker and reflected light from the blades can also cause problems. These light disturbances are experienced inside the home as well as outside.

In April 2005, the BBC reported that the owners of a wind turbine near a top-security prison (Whitemoor Prison in Cambridgeshire) have agreed to turn the turbine off in the early mornings to prevent possible 'security problems' because the prisoners were becoming upset by the flickering shadows.

8. Threat to wildlife and livestock

The construction process, with access roads and links to the grid, endangers wildlife habitats. There is considerable evidence from around the world that spinning blades have killed huge numbers of birds. Bats kills are also a serious problem.

According to the RSPB, birds may be scared away from their ususal locations during construction and/or operation of wind turbines. Access roads and buildings may destroy feeding, breeding and roosting sites. Birds may fly into the towers or the blades, especially during storms and conditions of poor visibility.

The RSPB is opposing plans to build hundreds of turbines on the Isle of Lewis, claiming it is illegal because of its status as an internationally important bird sanctuary.

The turbines at Altamount Pass in California, the largest wind-farm development area in the world, kill an estimated 5,500 birds a year. A US wildlife expert has launched a lawsuit against the wind farm. 

A report by the US National Research Council (3 May 2007) confirms that bats are the main victims of land-based US wind turbines. Two species - the hoary bat and the eastern red bat - suffer most, accounting for over 60% of the 2,500 kills recorded (see ref 19).

A study by the University of Calgary in Canada suggests that 'exploding lungs' may be the reason for the large numbers of dead, but apparently unharmed, bats found around wind turbines. The moving blades cause a drop in pressure that makes the delicate lungs of bats suddenly expand, bursting the tissue's blood vessels. This is known as a barotrauma, and is well-known to scuba divers. 

Click here to read the full article in the New Scientist.

David Bellamy has recently called for a ban on wind farms on the grounds that they 'chop up birds'. Although the blades can appear to be rotating slowly, the tip speed of a blade can reach 300km per hour or more.

A study carried out in northern Spain found that about 6,000 birds and hundreds of bats were killed by turbines in a year (see ref 15).

In 2008, the Regional government of Valencia, Spain, ordered 2 wind-farms to be shut down after they butchered 200 griffon vultures and 100 more birds (official figures, possibly still shy of reality, especially the 100 birds..). The owning company won't comply, and will appeal the decision.

To see pictures of wind-farm bird kills in Spain, click here.

In Wales, wind farms are being proposed near habitats of red kites.

The noise and light pollution mentioned above may also be harmful to livestock. The British Horse Society has expressed concerns about the effects that low-frequency noise, unexpected start-up and shadow flicker may have on horses.

9. Jobs and tourism

Evidence from Europe suggest a 40% drop in tourism in areas where there are wind farms. The 2002 Visit Scotland Survey of visitor attitude showed that tourists avoid landscapes with wind turbines. Tourism earns £2 billion a year for Wales. It contributes 7% to the GDP. Agriculture contributes 2%; the electricity industry also contributes 2%. A typical wind farm employs one maintenance person.

The effects of a drop in tourism will be felt most keenly in rural areas. Most tourists come to Wales to enjoy the peace and tranquillity of the countryside and to engage in outdoor activities. Wind farms are incompatible with this type of tourism. The result will be fewer visitors to rural areas and, therefore, fewer tourism-related jobs in communities where employment opportunities are already very limited. MLAG is aware of three rural business enterprises: a game shoot and two sound studios, whose continued existence is under threat from proposed wind farms. All these businesses employ local people, and visits from clients from outside the area to these businesses are a benefit to the local economy. The closure of these businesses will be a loss to the local community.

10. House prices

Evidence from Denmark, the USA and the UK indicates that houses in the vicinity of turbines lose 25 to 30% of their value. Houses close to a turbine could be unsalable.

There has been a legal ruling against a couple in the Lake District who sold their house without telling the buyers that a wind farm was likely to be built nearby. The judge upheld the purchasers' claim that their house had been devalued by noise pollution, light flicker and damage to visual amenity caused by wind turbines and ordered the vendors to pay compensation of 20% of the purchase value of the house.

In May 2005, a local resident near Brechfa reported in the Carmarthen Journal that:

"Our property, in the middle of the proposed TAN8 site (Strategic Area G) had a firm offer of £318,000. One week later our prospective purchaser, who incidentally knew about the turbines and had no problem with them, said they would do us a favour and take it off our hands at a big financial risk - for a reduced £250,000 which was higher than the 40 per cent we could expect to get, being near turbines!"

In July 2005, a study was made of a sample of properties near a proposed wind farm at Esgairwen Fawr, near Lampeter, Ceredigion, by Gareth Scourfield. Eight properties were valued and estimates made of the loss due to nearby wind turbines. Total loss for the eight properties was in excess of £1.5 million, or typically 20 – 25% on each property (see ref. 16).

11. The economics of wind power

Wind power is one of the most expensive forms of electricity; it survives on direct and indirect subsidies. This extra cost to taxpayers is not good value because wind energy cannot provide firm generating capacity nor can it make a significant contribution in reducing greenhouse gas emissions.

An article in The Telegraph, dated Monday August 10, 2009, quotes from the Government's Renewable Energy Strategy with plans to increase the proportion of Britain's energy generated by "green" sources is set to cost between 11 and 17 times what the change brings in economic benefits. The figures are buried deep in the Strategy paper produced in July. According to the document, while the expected cost will total around £4bn a year over the next 20 years, amounting to £57bn to £70bn, the eventual benefit in terms of the reduced carbon dioxide emissions will be only £4bn to £5bn over that entire period.

According to the most recent figures from the industry regulator, Ofgem, there were more than 16m ROCs in the year to March 2008, worth £872m. That is an extra £872m on the bills of every household and business in the UK supplied with electricity – in just one year.

An article in the Daily Mail, dated July 10, 2009, highlighted the "Green Fuel shock":

"Millions of families face being hit with higher fuel bills to pay for a new 'green energy revolution' due to be unveiled by Labour next week. The levies on the price of gas and electricity  -  dubbed 'green stealth taxes' by critics  -  will help pay for renewable energy to tackle climate change, including building 7,000 wind turbines over the next 11 years.
Industry experts warn the cost of subsidising renewables will increase household energy bills. At present the renewables element of the typical bill is an average £55 a year, but this could increase to as much as £120 by 2014. The respected UK Energy Research Centre has predicted that by 2050 the subsidy will cost the economy at least £17billion a year, the equivalent of an extra £700 a year per household."

Click here to read the full article.

The only comfort to be drawn from this is that there is no possibility of the wind industry installing as many as 7000 turbines and all the associated infrastructure over the next 11 years in the current economic climate.

In a recent (Nov 2008) paper by Professor Michael Jefferson, he highlights the  exaggerated claims made by the wind energy industry about its efficiency in terms of actual and likely capacity factors achieved. Underpinning this paper are the capacity factors achieved by wind energy developments in England in 2007, derived from official sources, and the rewards calculated to have been accumulated by developers. These rewards are largely the result of subsidies provided by business and domestic electricity customers in the UK, a fact that is not widely known - partly because both the industry and the government misleadingly claim, “there is no public subsidy for wind energy”. Professor Jefferson makes recommendations for achieving a more open and challenging planning framework where technical and commercial claims can be properly tested.

Click here to download a copy of his paper in MS Word format (see ref 21).

According to a report by the Royal Academy of Engineering in 2004 (see ref 17) the cost of generating electricity from onshore wind farms is 5.4 pence per kWh with standby generation. The cost of generating electricity from offshore wind farms is 7.2 with standby generation. (The cost of the standby generation capacity was based on the cost of an open-cycle gas turbine, which is the cheapest new plant option.) In comparison, the cost of generating electricity from gas-fired (CCGT) plant is 2.2; from nuclear fission plant, it is 2.3, which includes decommissioning costs. (Decommissioning costs are assumed to be neutral in the calculations for the cost of wind power.)

Diagram from ref 17

According to Ofgem, the Labour government's wind subsidies currently stand at £485 million a year.

"Wind farms get around three times as much in subsidy - a mixture of selling ROCS [renewable obligation certificates] and a share of fines paid by non-renewable plants - as they do from selling electricity" (see ref 18)

Wind turbines are a quick and cheap way for power companies to avoid penalties for not meeting government targets on renewables and for gaining subsidies.

The Renewable Obligation subsidy system pays for wind power at the point of generation, not delivery. This means that even the wind-generated electricity that is lost in transmission or wasted because it is generated when there is no demand is rewarded with government subsidies. The Committee of Public Accounts Report on Renewable Energy, published in September 2005, concluded that the Renewable Obligation subsidy system gives undue support to wind power at the expense of other renewable technologies. This report estimated that the Renewable Obligation subsidy system will be adding £1 billion a year to electricity prices by 2010. The expansion of distribution and transmission capacity needed to meet the government’s 10% renewables target will add another £1.5 billion to consumer costs.

Even the CEO of E.ON UK (formerly Powergen) is on record as saying:

"Without the renewable obligation certificates nobody would be building wind farms."

12. Radar Interference

Aviation safety is one of the main reasons why plans to build wind farms are held up. The concern is that they interfere with the radar used in air-traffic control. Some people even argue that they could be used as cover by terrorists or enemy aircraft in time of war. In Britain such worries have caused the shelving or refusal of more than 40 proposed wind farms.

The standard radar used by air-traffic control centres can see a long way, but finds it difficult to tell between a moving aircraft and the whirling blades of a wind turbine. Radar works by sweeping a pulsed radio signal around a wide area and then measuring the time it takes for the signal to be reflected back by any objects in its path. This allows the position of those objects to be plotted on a screen. Aircraft can normally be distinguished from stationary objects because the Doppler effect changes the frequency of the returned signal.

Although a wind turbine does not change position, its blades are moving and these also cause a Doppler effect. The returning signal from a wind turbine thus creates illuminated blobs on a radar screen that look just like moving aircraft. Moreover, the blobs do not keep still because every four seconds or so, as the radar beam sweeps past, the signal is bounced back by different parts of the turbine’s blades in unpredictable and confusing ways. The clutter this causes on the screen is made worse when the signal is bounced around between different turbines in the same farm. The result is that wind farms can be impossible to filter out because the resolution of a typical long-range radar is not high enough to detect the difference between the Doppler effect caused by an aircraft and that caused by a wind turbine. (see ref 20)



  1. The Wind Power Report ED 3 2006  published by ABS Energy Research, an independent energy market research company.
  2. Wind Report 2004, E.On Netz: Bayreuth, 2004.
  3. Hugh Sharman, ‘Why wind power works for Denmark’ Civil Engineering 158, May 2005.
  4. David White, BSC, C Eng, FI Chem E ‘Reduction in Carbon Dioxide Emissions; Estimating the Potential Contribution from Wind-Power’ Commissioned and published by the Renewable Energy Foundation, December 2004.
  5. Blaengwen Wind Farm Environmental Statement, Entrec Ltd, 7 January 2005.

  6. Wind Energy Fact Sheet 14: Energy and Performance, DTI: August 2001, page 4.

  7. Hugh Sharman, ‘Why UK wind power should not exceed 10 GW’ Civil Engineering 158, November 2005.

  8. V. C. Mason, ‘Wind power in West Denmark: Lessons for the UK‘, October 2005 See

  9. Europe's Ambitions: Building the world's biggest wind turbine. National Geographic magazine, August 2005.

  10.  ‘An ill wind an objection to wind farms in Ireland’ by Nigel Barnes See

  11. R. A. Lindsay and O. M. Bragg, Wind Farms and Blanket peat: The Bog Slide of 16th October 2003 at Derrybrien, Co. Galway, Ireland . University of East London, 2004.

  12. Reported in Dominion Post, 16 November 2005.

  13. G. P. Van den Berg, ‘Effects of the wind profile at night on wind turbine sound’, Journal of Sound and Vibration, Vol. 277, 2004.

  14. D. M. J. P. Manley, P. Styles and J. Scott ‘Perception of the Public of Low Frequency Noise’ Journal of Low Frequency Noise, Vibration and Active Control, Vol. 21 No 1 2002.

  15. See

  16. Gareth Scourfield, ‘Report on a sample of properties inspected near a proposed wind farm at Esgairwen Fawr, near Lampeter, Ceredigion’ July 11, 2005.

  17. "The Cost of Generating Electricity". A study carried out by PB Power for The Royal Academy of Engineering, 2004. ISBN 1-903496-11-X.

  18. The Economist, 18 March 2004.

  19. "Bats Take a Battering", article in The New Scientist, May 12, 2007.

  20. The Economist, 8 November, 2008.

  21. Professor Michael Jefferson, 'A Critical Note on the Efficacy of the UK's Renewable Obligation System as it Applies to Onshore Wind Energy Developments in England', Centre for International Business and Sustainability, London Metropolitan Business School, November 2008.

  22. Barbara J Frey, BA, MA and Peter J Hadden, BSc, FRICS on "Noise radiation from wind turbines installed near homes: effects on health". February 2007. 

  23. Dr. Sarah Myhill, "The Carbon Equation for Individual Wind Farms". January 2009.

[Return to the top of the page]


Mynydd Llansadwrn

What the politicians say

Latest News

Wind Turbine Facts

Renewable Energy

Energy Conservation

The Action Group