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1	Why are we building wind farms?

2	Is wind energy economically viable?

3	How big are wind turbines?

4	How strong does the wind have to blow for the wind turbines to work?

5	How much electricity does a wind turbine generate?

6	What happens when the wind doesn't blow?

7	What is the Renewables Obligation?

8	Are wind turbines safe?

9	Are wind turbines noisy?

10	Is a wind farm a 'get rich quick' scheme?

11	Are we likely to see more wind turbines?

12	I thought wind farms were moving offshore, why do we still need onshore development?

13	How many jobs will be created?

14	I have heard that wind turbines might affect TV reception. Is this true?

15	Do wind turbines frighten livestock?

16	How long does it take for a turbine to "pay back" the electricity used to manufacture it?

17	Does wind farming affect tourism?

18	How long do wind turbines last?

19	What is shadow flicker?

20	Do wind turbines really only operate for 30% of the time?

21	Are there any health issues from wind turbines?

22	What can I do to help wind energy?

23	Should I visit a wind farm?

24	Do wind turbines produce low frequency noise?

25	How does a wind turbine make electricity?

26	Someone told me something about wind farms and I want to know if its true?

27	How will a wind farm change the value of my house?

Q. Why are we building wind farms?

A. To address the challenges of security of energy supply and climate change caused by emissions of carbon dioxide from traditional power stations. Locally produced renewable energy, like wind farms, is part of the solution to decrease reliance on overseas oil, gas, coal and uranium. The Royal Commission on the Environment concluded that the UK needs to move towards reducing harmful Carbon Dioxide emissions to 60% of 1997 levels by 2050.(http://www.rcep.org.uk/energy.htm). As a result the Government is introducing a number of measures to achieve this, including the obligation to secure 10% of the UK's electricity supply from renewable energy by 2010. The Energy White Paper published in February 2003 set the ambition of doubling this target between 2010 and 2020. Wind energy is the most economic renewable energy resource available in the UK.

Q. Is wind energy economically viable?

A. The economics of generating electricity from the wind have improved greatly over the last ten years. The price of electricity generated by wind turbines is comparable to that of any new build gas power station and by and large cheaper than any new coal station fitted with clean-coal technology.

Q. How big are wind turbines?

A. Large modern wind turbines have rotor diameters ranging from 60 up to 100 metres; towers range from 60 to 100 metres in height. Hence the tip of the top blade can be anywhere from 90m to 150m above the ground. There are now prototype wind turbines 200m high, in Germany.

Q. How strong does the wind have to blow for the wind turbines to work?

A. Wind turbines start operating at wind speeds of 3 to 4 metres per second (around 7 to 9 miles per hour) and reach maximum power output at around 15 metres per second (around 34 miles per hour). Wind turbines, on average, generate electricity for around three-quarters of the year. At very high wind speeds, i.e. gale force winds, (25 metres per second, 56 miles per hour) wind turbines shut down. The higher you go, the windier it is, and so even if you can only feel a gentle breeze at ground level, there is enough wind to power the turbine at the top of the tower.

Q. How much electricity does a wind turbine generate?

A. One 2 MW wind turbine on a typical site can produce enough electricity to meet the annual needs of over 1,000 households.

Q. What happens when the wind doesn't blow?

A. When the wind stops blowing, electricity continues to be provided by other forms of generation, such as gas, coal and nuclear. Our electricity system is mostly made up of large power stations, and the system has to be able to cope if one of these large plants goes out of action. It is possible to have at least 20% of the country's needs met by intermittent energy sources such as wind energy, without having to make any significant changes to the way the system operates. A recent Oxford University study “Wind Power and the UK Wind Resource“ (www.eci.ox.ac.uk/renewables/ukwind) has found that there would never be a situation across the UK where the wind does not blow enough for wind turbines to generate electricity.

Q. What is the Renewables Obligation?

A. The Government has introduced an obligation (Renewables Obligation) on all electricity supply companies to increase, on an annual basis to 15% by 2015, the proportion of our electricity sourced from renewable energy sources such as the wind. If a company fails to meet its annual renewable production targets then it will have to pay a fine into a central pool managed by Ofgem (the electricity regulator), which is proportional to its shortfall of renewable energy. This fine is then paid (“recycled”) back to those suppliers who have met their obligation. Over time if a supply company continues to perform badly in this area relative to its competitors then it will find it progressively more difficult to keep the cost of the electricity it supplies at a competitive level.

Q. Are wind turbines safe?

A. Wind energy is one of the safest energy technologies. No member of the public has ever been killed by wind energy or wind turbines anywhere in the world, despite the fact that there are now over 68,000 operational wind turbines.

Q. Are wind turbines noisy?

A. Wind turbines are not noisy. It is possible to stand underneath a turbine and hold a conversation without having to raise your voice. As wind speed rises, the noise of the wind masks the noise made by wind turbines. Developers must comply with strict noise criteria, which have been established by the DTI to protect nearby residents from any potential noise nuisance. Why not visit a wind farm and experience it for yourself?

Q. Is a wind farm a 'get rich quick' scheme?

A. No, wind energy projects take, on average, at least four years to develop before generating any revenues at all (and not all gain planning permission even at this stage) and thereafter only deliver a reasonable return after 20 years of operations (akin to most energy or large scale infrastructure projects).

Q. Are we likely to see more wind turbines?

A. Given the 15% target established for 2015, and the longer terms goals proposed by the Government, it is inevitable that renewable energy in its many forms is going to be an increasingly visible, necessary and familiar part of our world if we all wish to maintain our present lifestyles.

Q. I thought wind farms were moving offshore, why do we still need onshore development?

A. There are currently four operational offshore wind farms in UK waters. It is still a lot more expensive to have offshore wind farms, and still requires further support by the government, although the price of offshore wind energy is coming down. Further offshore projects are currently proposed for UK waters, however their development and construction will take a lot longer to deliver as experience is gained from the current offshore wind farms in the UK and Europe. We need both onshore and offshore projects to make a real difference in are greenhouse gas emissions.

Q. How many jobs will be created?

A. During development and construction the skills and expertise of consultants, contractors and suppliers are continually called upon. If you are a competent supplier or contractor then we will be pleased to hear from you, please contact us using the feedback form.

During a projects operating phase, part-time operational and maintenance engineers are required. Typically this involves visiting a site (on average) once per week.

The real job creation and maintenance is in supporting the UK companies manufacturing wind turbines, related components and their operation and maintenance such as Vestas blade factory on the Isle of Wight and in Southampton, Vestas Celtic Wind Technology in Campbelltown and REpower-Peter Brotherhood in Peterborough.

Q. I have heard that wind turbines might affect TV reception. Is this true?

A. Some interference to analogue TV reception is possible, however this is normally identified pre-construction by taking “before and after” measurements and can be easily remedied.

Q. Do wind turbines frighten livestock?

A. Wind farming is popular with farmers, because their land can continue to be used for growing crops or grazing livestock. Wind turbines do not disturb sheep, cows and horses. Delabole Wind Farm in Cornwall even houses a riding school.

Q. How long does it take for a turbine to "pay back" the electricity used to manufacture it?

A. The comparison of energy used in manufacture with the energy produced by a power station is known as the "energy balance". It can be expressed in terms of energy "pay back" time, i.e. as the time needed to generate the equivalent amount of energy used in manufacturing and installing the wind turbine or power station.

The average wind farm in the UK will pay back the energy used in its manufacture and installation in its first year of operations.

Q. Does wind farming affect tourism?

A. There is no evidence to suggest that wind farms detract tourists (and many studies have now been carried out), indeed many wind farms are themselves tourist attractions and enhance the local tourism economy.

Q. How long do wind turbines last?

A. A wind turbine typically lasts around 25 years. During this time, as with a car, some parts may need replacing and on-going maintenance is required. At the end of its life the wind farm is decommissioned and all visible traces of the wind farm to be removed such that a subsequent visitor would never know it has been there. Should a developer wish to extend the life of the development, then a fresh planning application would be required.

Q. What is shadow flicker?

A. When the sun is shining, all objects create a shadow, and if the object causing the shadow is moving, then the shadow moves also. Shadow flicker is caused by the rotating wind turbine blades creating a rotating shadow, when the sun is shining, which falls across a narrow window into a building. When this is the case, it could be a nuisance.

To prevent this potential problem the path of the sun can be mathematically calculated and can be modelled in a computer program. We then avoid siting turbines where they will cause problems OR If we calculate that unwanted shadow flicker may occur at certain locations at certain times, we can control the turbine to make it shut down for a few minutes at these particular moments in the year.

Q. Do wind turbines really only operate for 30% of the time?

A. No. A modern wind turbine produces electricity for around three-quarters of the year, but it generates different outputs dependent on wind speed. For instance, a 1MW wind turbine generates different levels of power, up to a maximum of 1MW, depending on the strength of the wind. Over the course of a year (which is 8,760 hours) a 1MW diesel generator running at maximum output (1MW) and continually (assuming no downtime for proactive or reactive maintenance) will produce 8,760 MWhrs (megawatthours) of energy (one megawatthour equals 1,000 kilowatthours – the standard "unit" of electricity in the UK). Whereas a wind turbine will be working say 80% of the time and sometimes be generating maximum output (1MW) sometimes (0.5MW) and sometimes nothing. However its overall energy output is around 25-30% that of the diesel generator, but it is working around 80% of the time.

Q. Are there any health issues from wind turbines?

A. There are no direct health effects from the level of noise generated by wind turbines. It has been repeatedly shown by measurements of wind turbine noise undertaken in the UK, Denmark, Germany and the USA over the past decade, and accepted by experienced noise professionals, that the levels of infrasonic noise and vibration radiated from modern, upwind configuration wind turbines are at a very low level; so low that they lie below the threshold of perception, even for those people who are particularly sensitive to such noise, and even on an actual wind turbine site.

In response to concerns that wind turbines emit infrasound and cause associated health problems, Dr Geoff Leventhall, Consultant in Noise Vibration and Acoustics and author of the Defra Report on Low Frequency Noise and its Effects, says: “I can state quite categorically that there is no significant infrasound from current designs of wind turbines.”(www.bwea.com/pdf/lfn_summary.pdf)

We encourage anyone with specific health concerns to contact us via the questionnaire, please click on Engage in Consultation.

Q. What can I do to help wind energy?

A. One of the most helpful things you can do is to help us win the debate on wind energy. Respond to letters in local and national papers, write to the local planning authority at the council, write to councilors themselves, participate in radio phone-in programmes and wherever else the opportunity arises. There are innumerable independent national polls that show well over three-quarters of the population support wind energy – please don't be one of the silent majority and support wind.

Q. Should I visit a wind farm?

A. Visiting a wind farm is a great way to understand the reality, please sign up for a wind farm trip by clicking on Engage in Consultation.

Q. Do wind turbines produce low frequency noise?

A. There is always low frequency noise present in any ambient quiet background and it can be produced by a variety of sources, including industrial machinery, cars, fridges, TVs and natural sources such as the sea, wind and thunder. It has been repeatedly shown by measurements of wind turbine noise undertaken in the UK, Denmark, Germany and the USA over the past decade, and accepted by experienced noise professionals, that the levels of low frequency noise and vibration radiated from modern, upwind configuration wind turbines are at a very low level; so low that they lie below the threshold of perception. There are no direct health effects from noise at the level of noise generated by wind turbines.

Q. How does a wind turbine make electricity?

A. The simplest way to think about this is to imagine that a wind turbine works in exactly the opposite way to a fan. Instead of using electricity to make wind, like a fan, turbines use the wind to make electricity.

Almost all wind turbines producing electricity consist of three rotor blades which rotate around a horizontal hub. The hub is connected to a gearbox and generator, which are located inside the nacelle. The nacelle is the large part at the top of the tower where all the electrical components are located.
Most wind turbines have three blades which face into the wind; the wind turns the blades round, this spins the shaft, which connects to a generator and this is where the electricity is made. A generator is a machine that produces electrical energy from mechanical energy, as opposed to an electric motor which does the opposite!

Q. Someone told me something about wind farms and I want to know if its true?

A. Either click on Engage in Consultation and ask us the question, or go to the links and downloads page to see other sources of information.

Q. How will a wind farm change the value of my house?

A. The Royal Institute of Chartered Surveyors (RICS) undertook a survey (RICS, 2004) of its members to discover this. However their results are still inconclusive. The survey shows that of the chartered surveyors with experience of house transactions near to wind farms. 40% indicate no affect and 60% indicate some negative affect on house prices, with most saying the biggest impact is at the time of the planning application.They also stated that within two years of the wind farm becoming operational house prices recover. Experiences from around the country shows us that wind farms are generally welcome neighbours once they become operational.