We understand that many people will not have encountered a wind farm before, and may have some concerns about having one proposed in their locality. Below are some of the most common questions which are often asked. Many of these issues have been addressed over the years by independent experts and there is a variety of useful publications available for further information, such as the Sustainable Development Commission’s recent report ‘Wind Power in the UK’. Other useful sources are given at the end.
How efficient are wind turbines?
Using a free and infinite fuel source - the wind - to meet our power needs is about as efficient as you can get. The technology is efficient too. Modern wind turbines are operational for 70-85% of the time and over the course of the year they will generate, on average, up to 35% of the theoretical maximum output1. This is known as a load or capacity factor. The exact figure is dependent on the location, technology, size, turbine reliability and wind conditions. By comparison, the load factor of conventional power stations is on average 50%2. A typical modern 2.3MW wind turbine can produce enough power for over 1,000 homes - and that is taking into account the fact that the wind doesn’t blow all the time.
Each operational wind farm typically pays back the electricity consumed in making, installing, operating and decommissioning the wind farm in the first 3-10 months of its 20 year life.3
Will wind farms make one jot of difference to global warming?
To date 74,223MW of wind energy capacity has been installed worldwide4, generating around 154 tWh annually and employing 150,000 people. That is saving as much as 133 million tonnes of CO2 every year and meeting the domestic electricity needs of more than 31 million people5.
That's hardly insignificant in our efforts to slow down dangerous climate change.
Every unit of power generated by a wind turbine displaces a unit of power that would otherwise come from a fossil-fuel power station and therefore reduces polluting emissions. While some fossil-fuel back up is needed because of the intermittent nature of wind power, this will be minimal and still result in an overall reduction in greenhouse gas emissions.
But what happens when the wind stops blowing?
Your electricity will still work in the usual way. Electricity grids are designed to cope with peaks and troughs in supply and demand, for example when we all put the kettle on during TV commercials or when a nuclear power station has a safety 'outage'. Power generated by other sources acts as a backup to ensure that you always have access to electricity. Wind energy outputs can be predicted quite accurately hours in advance and the variations are smoother than conventional generation, making it easier for the system operator to manage changes in supply6.
Are wind turbines noisy?
Modern wind turbines are surprisingly quiet. You can stand right underneath the blades and still hold a conversation without raising your voice. We follow rigorous and independent noise standards when designing our projects and we would not locate a turbine where it could cause statutory noise nuisance to local residents. This aside, wind farms are subject to strict planning conditions that monitor noise levels to guarantee that they never exceed specific levels.
But aren't most people against wind turbines?
Absolutely not. Despite what you might read in the papers, wind power is popular with the general public and with communities in which wind farms are already operating. In Europe a recent Eurobarometer survey of 24,815 people from 25 EU countries showed that 71% support wind power, 3% oppose, 14% are indifferent and 5% do not know where their opinions lie. The survey also showed that support for gas, oil, coal and nuclear energy fell far short of that for wind power. Gas received the most positive support with 42% in favour and 7% opposed; nuclear energy was the least favourable with 20% in favour and 37% opposed7.
In the UK approval is over 80 per cent among those within five kilometres of a wind farm8. Furthermore, there is evidence following a comprehensive study by the Scottish Executive that those living nearest to wind farms are their strongest advocates9.
In America no large scale representative poll has been carried out, however there is evidence from polls carried out within states and areas of wind power development that wind power recieves much support. In Massachusetts, a poll concerning the Cape Wind offshore development found that 81% of adults and 61% of locals supported the project, opposition was just 14% statewide and 36% locally10. In a poll published by the Lawrence Journal in which 447 people took part, 76% of people supported the development of more wind farms in rural Kansas, with 20% in opposing11. A poll carried out by Telephone Strategies Group in Tennessee of 1047 voters found that 74.5% support the increased use of wind energy within their state, only 6.2% opposed and 19.3% were undecided12.
Across the world surveys show that wind power recieves support from a large majority of the public in which ever country it is developed.
Do wind turbines affect property prices?
Studies published in November 2004 by the Royal Institution of Chartered Surveyors (RICS) and leading chartered surveyors Knight Frank show either that there is no conclusive evidence to confirm any impact, or if there is some impact, it is not long lasting.
A further RICS study was published in March 2007. The summary said, "Despite initial evidence that there was an effect, when investigated more closely, there were generally other factors which were more significant than the presence of a wind farm. Insofar as there was any impact on prices, the results seem to show that it is most noticeable for terraced and semi-detached houses, with there being a significant impact on properties located within a mile of the wind farm. The effect seems much less marked – if at all – for detached houses”.13
Another study published in November 2004 by leading chartered surveyors Knight Frank LLP undertaken on behalf of the BWEA concluded that there is insufficient market evidence to determine whether an existing wind farm has affected residential property prices. This is linked to the wide range of factors that can be involved in determining house prices, not just wind farms14.
Contrary to the claims that wind farms will negatively affect property prices, emerging research demonstrates that the proximity of a wind energy development does not adversely affect property prices. In two opinion polls conducted by Robertson Bell Associates15, an independent market research agency and member of the Association of British Market Research Companies, the results were as follows:
o Taff Ely Wind Farm, South Wales: 70% of respondents say they are able to see the wind farm from their home. In regard to house prices, more than three in four (78%) say the wind farm has had no effect, with a further 15% saying 'don't know'. As many residents say house prices have increased a little because of the wind farm (3%) as say they have decreased a little (3%), similarly, as many say they have increased a lot (1%) as say decreased a lot (1%).
o Novar Wind Farm, Scotland: In regard to house prices, almost three in four (72%) say the wind farm has had no effect, with a further 26% saying 'don't know'. None of the respondents say house prices have decreased as a result of the wind farm. Indeed, 1% say house prices have increased a little because of the wind farm.
In America the Renewable Energy Policy Project (REPP) released results from an extensive study based on 25,000 homes within a 5 mile radius of various wind farms16. The report showed no change in values other than a small increase, which is likely to be due to a general increase in property prices rather the benefits of a wind farm in the local area. The report stated the following: 'If property values had been harmed by being within the view-shed of major wind developments, then we expected that to be shown in a majority of the projects analyzed. Instead, to the contrary, we found that for the great majority of projects the property values actually rose more quickly in the view shed than they did in the comparable community. Moreover, values increased faster in the view shed after the projects came online than they did before. Finally, after projects came online, values increased faster in the view shed than they did in the comparable community. In all, we analyzed ten projects in three cases; we looked at thirty individual analyses and found that in twenty six of those, property values in the affected view shed performed better than the alternative.'
Another American report carried out by ECONorthwest was based on a nationwide survey conducted of tax assessors in areas with wind power projects, the report found no evidence to supporting the claim that views of wind farms decreased property values17.
Further anecdotal evidence is provided from the UK. In the market town of Swaffham in Norfolk, there are two large turbines very close to the town centre. A local resident, Dave Cunnington, moved into his house without knowing that the second wind turbine (the UK’s largest at the time) was going to be built. He said to the Sunday Times newspaper18 that he wasn’t too concerned about the effect on the price of his house; "…But if you’re evergreen, and a lot of people are, then it wouldn’t affect the value." Paul Brewster, Branch Manager of Abbott’s Estate Agents in the town, reflects this point of view, "There was concern when the first one went up four years ago that it might have an adverse effect on property values, but we didn’t lose any sales, nor did we have to reduce prices."
Is wind power expensive?
No, wind is in fact a very competitive source of energy generation. A study published in Wind Power Monthly19 about the costs of generation around the world found that 'Wind is already competing with coal, it is cheaper than nuclear and cheaper to exploit at large scale than any of the other renewable energy sources. In some regions it can be competitive with gas-fired generation today.'
The generation costs of onshore wind power in the UK are around 3.2p/kWh, with offshore at around 5.5p/kWh. This compares to a wholesale price for electricity of around 3.0p/kWh.20
In Europe generation costs of onshore power are between 4 c€/kWh and 6 c€/kWh, with offshore at between 7 c€/kWh and 9.5 c€/kWh. This price compares to coal and gas generation prices at around 3.7 c€/kWh in Belgium, 4.5 c€/kWh in Denmark, 4 c€/kWh in the Netherlands and 4.5 c€/kWh in Spain.21
In the USA wind power is very competitive, providing energy at a cheaper rate than the average electricity retail price. Wind energy costs around 4-6 cents/kWh22 compared to an average fossil fuel price of 8.74 cent/kWh23.
And the future looks even brighter for wind power as the cost of generation is likely to fall due to improved turbine technologies. Additionally the cost of finite fuels like gas and oil are likely to rise as natural reserves are depleted. Also when the social and environmental costs of polluting emissions and climate change are taken into account, the cost of wind power is even lower.
Are there any health implications of living near to a wind farm?
No, none. Turbines do not produce any emissions, harmful pollutants or waste products that could damage health or wildlife. Despite claims that infrasound (sound with a frequency too low to be heard) may damage health, many reports have been published dispelling this claim. RES is not aware of any report that confirms the existence of turbines producing negative effects on health.
In 2004 Bel Acoustic Consulting, on behalf of the Energy Efficiency and Conservation Authority, carried out a review of 12 reports concerned with the existence, measurement and affects of infrasound in relation to wind turbines24. Included within these 12 reports were all the major reports carried out on infrasound and turbines, and reports that have been used to support the claim of negative health impacts. The conclusion of the report stated; &quo;there is no evidence to indicate that low-frequency sound or infrasound from current models of wind turbine generators should cause concern.&quo;
In fact, it is often the case that evidence for health impacts of low frequency noise come from misrepresentations of reports. One DEFRA report by Dr Geoff Leventhall25 is so often misrepresented by campaigners that he was prompted to say: "I can state quite categorically that there is no significant infrasound from current designs of wind turbines. To say that there is an infrasound problem is one of the hares which objectors to wind farms like to run. There will not be any effects from infrasound from the turbines."
RES follows strict Health and Safety guidelines during the development, construction and operation of all our wind farms. Public footpaths running through several wind farms, including one of our own in Lancashire, are regularly used by walkers and horseriders, who pass within metres of operating turbines.
What is the lifetime of wind turbines?
The expected lifetime of a wind farm is typically 20 years from the date of commissioning. At the end of this period, a decision would be made to replace or remove the turbines. If a decision were taken to decommission the wind farm, this would involve dismantling and removing from site the turbines and associated infrastructure, restoring the land to its former state. Usually the foundations are buried and graded over with top soil as removing them would cause more land damage than leaving them in situ.
Who decides how many turbines are erected, and how large they are?
Wind farms are best located away from people's homes, but where the wind blows. In economic terms, too few, too small, would not make sense, but the usual planning laws govern their size and number. We also make an assessment during the planning and development of a project about what size and design of project would be appropriate for a given area, and we encourage feedback from the local community about this. Claims about the whole of the countryside being covered in turbines are exaggerated. Each application would have to go through the usual planning process, during which communities have an opportunity to make their views known.
Further information:
‘Wind Power in the UK’ by the Sustainable Development Commission, May 2005, and accompanying summary booklet ‘Wind Power - Your Questions Answered’, both available to download from http://www.sd-commission.org.uk/
Department for Trade and Industry - www.dti.gov.uk/renewables
‘Wind Power: your questions answered’, Friends of the Earth, 2003. http://www.foe.co.uk/
Sustainable Development Commission (2005) Wind in the UK
- Sustainable Development Commission (2005) Wind in the UK
- SERA (2005). Our Energy Future: The Role of Wind Power Available on http://www.bwea.com/pdf/SERA-briefing.pdf
- Sustainable Development Commission (2005) Wind Energy in the UK
- GWEC Global Wind 2006 Report
- The tWh stat is estimated with the European capacity factor of 0.238, worked out from GWEC Global Wind 2006 Report. The employee and domestic electricity stats are proportional to the GWEC 2005 stats. CO2 statistic created with (A x 0.3 x 8760 x 86) /1000 where A = rated capacity in MW, 0.3 is the capacity factor, 8760 is number of hours in a year and 860 is the grams of CO2 emitted by a typical coal-fired power plant per kWh of electricity generated.
- Sustainable Development Commission (2005) Wind Energy in the UK
- European Commission (2006). Energy Technologies: Knowledge – Perception – Measures http://ec.europa.eu/research/energy/pdf/energy_tech_eurobarometer_en.pdf
- NOP World, August 2004
- MORI (2003) Public Attitudes to Windfarms; A Survey of Local Residents in Scotland, Scottish Executive Social Research.
- http://www.civilsocietyinstitute.org/media/news.cfm
- http://www2.ljworld.com/polls/2007/jun/should_more_wind_farms_be_allowed_rural_kansas/
- http://www.invenergyllc.com/forms/Powerful_Wind_Energy_Support_TN.pdf
- http://www.rics.org/NR/rdonlyres/63D1BF3E-A608-45CD-8086-A6E7924D7F14/0/WindfarmsFiBREversionthreelowres.pdf
- www.bwea.com
- RBA 1997, 1998. Commissioned by National Wind Power (now npower renewables)
- REPP (2003). The Effect of Wind Development on Local Property Values, Sterzinger et al http://www.crest.org/articles/static/1/binaries/wind_online_final.pdf
- EconNorthwest (2006). Economic Impacts of the Kittias Wind Valley Project http://www.econw.com/reports/Economic-Impacts-Kittias-Wind-Project_ECONorthwest.pdf
- http://www.yes2wind.com/42_faq.html
- Wind Power Monthly (January 2004) – Wind Becomes Respectable
- Sustainable Development Commission (2005), Wind Energy in the UK
- www.ewea.org
- www.awea.org
- http://www.eia.doe.gov /
- EECA (2004), Low Frequency Noise and Infrasound from Wind Turbine Generators: A Literature Review, Bel Acoustic Consulting
- Defra (2003), A Review of Published Research on Low Frequency Noise and its Effects, Dr Geoff Leventhall, http://www.defra.gov.uk/environment/noise/lowfrequency/pdf/lowfreqnoise.pdf
