Spaldington Airfield
Wind Farm

1. How much of our renewable energy is provided by wind?

Over a quarter of renewable electricity is currently generated by wind energy and the share is growing. Other sizeable contributions are made from hydro, landfill gas and co-firing biomass in power stations.

Renewable UK (R-UK) tracks the number of wind farms and their capacity for electricity generation. According to these figures, 3,360 wind turbines had been installed by July 2011 with a combined capacity of over 5,553 MW, generating enough electricity equivalent to that used for over 3.1 million homes.  These wind turbines had the capacity to prevent the emission of 6,276,237 tonnes of carbon dioxide per year.  http://www.bwea.com/ukwed/index.asp

On average a single modern wind turbine will generate enough electricity to meet the needs of over a thousand homes over the course of a year, taking into account the fluctuations in wind speed.

2. Is wind energy reliable?

The strength and variability of the wind determines not only how much electricity can be generated by wind turbines but also how reliable electricity from the wind will be in meeting electricity demand.

The Environmental Change Institute at Oxford University produced the report ‘Wind Power and the UK wind resource (2005)’.  This looked into the availability of wind energy in the UK by analyzing hourly wind speeds collected by the Met Office at 60 locations across the UK between 1970 and 2003.

The Oxford University study used these wind records to identify patterns of wind power availability across the UK. It found that:

• Wind power availability is greater during winter than at other times of the year, and is on average stronger during the day than overnight
• Wind power delivers around two and a half times as much electricity during periods of high electricity demand as during low demand periods
• Low wind speed conditions affecting 90% of more of the UK would only occur in around one hour every 5 years during winter.

It concluded that there are distinct advantages of wind turbines being located in a range of locations, rather than being concentrated in one place. In effect, the impact of low wind speeds in any particular area can be smoothed by the generation in other windier parts of the UK as weather systems travel across the country. 

3. Does wind energy need 'back up' from other electricity generating sources?

All types of power-station need ‘back-up' as they can all break down unexpectedly, or be taken off-line by routine maintenance or for commercial reasons. In October 2007 for example almost half of the UK's nuclear power stations (6 out of 17) were off-line at once due to either faults or maintenance work.

Indeed, rather than requiring more conventional capacity to be built, increasing the amount of wind energy will allow older power stations to be shut down. The Oxford University Report mentioned above for example calculates that if 10% of UK electricity came from wind power, around 3,000 MW of conventional plant could be retired.  

The report ‘Common Concerns about wind Power’ (May 2011) produced by the Centre for Sustainable Energy (CSE) examines this question in detail, mentioning “the problem of ‘dispatch’, whereby supply of electricity is tailored to meet constantly changing demand, is not new to the industry.   Large unpredictable swings in the system are already balanced on a daily basis, and the grid is prone to critical failures for which significant reserve capability already exists; concluding “Wind farms offer a flexible, modular system that if implemented as a diversified resource with effective geographic spread can offer a reliable source of low-carbon energy, forming a core part of a mixed renewables portfolio in combination with a reduced platform of responsive conventional capacity”.

4. Will my electricity bills be higher?

A report commissioned by The Department of Energy and Climate Change in 2010 (‘UK Electricity Generation Costs Update’) showed that “estimates for onshore wind are now 9.4p/kWh.  However, to put this in context electricity from nuclear power is estimated to be 9.9p/kWh and electricity from gas 8.0p/kWh. Offshore wind is estimated to be more expensive, with costs of 15.7–18.6p/kWh (depending on wind farm location), although this is expected to fall to 11.0–12.5p/kWh for projects commissioned from 2020”.

The report ‘Common Concerns about Wind Power’ (May 2011) produced by the Centre for Sustainable Energy (CSE) examines this question in greater detail and comments further that “much of the environmental and social cost of conventional fuels is not reflected in the cost of generating electricity from conventional large scale plant, and effectively amount to additional public subsidies.  Internalising these costs completely would further increase the costs for energy generated from conventional fuel sources”.  The report also highlights that a paper, due to come out later this year, will attempt to quantify the full costs of coal generated electricity using a more comprehensive life cycle Analysis, including the impacts of natural resource depletion, wider ecological impacts and its contribution to climate change – suggesting that “the true cost of coal generated electricity could be tripled”.

5. How long does it take to pay back the energy used to manufacture the turbine?

The Sustainable Development Commission states in the report ‘Wind Power in the UK’ that the energy taken to build a wind farm is ‘paid back’ in around 3-10 months

A report by the World Steel Organisation concluded that the average wind farm will pay back the energy used in its manufacture within 6 to 9 months of operation. 

The CSE Report confirms this stating the average wind farm is expected to generate at least 20–25 times the energy required in its manufacture and installation over its lifetime, and the average energy payback time for a wind farm is in the region of 3–6 months.  The CSE report points to a study published in 2010 within the journal Renewable Energy, which compares the “Energy Return on Investment” (EROI) for a number of technologies.  Coal offers an energy return on investment of around 8 and nuclear around 9, while wind (operational and conceptual) had 25.2 (falling to 20 for operational only).  In other words, it shows that the average wind farm is expected to generate some 20-25 times more energy over its lifetime than was required in building and running it.

6. Are there potential health effects from wind farms?

Wind energy is a benign technology with no associated emissions, harmful pollutants or waste products. In over 25 years no member of the public has ever been harmed by the normal operation of wind turbines. In response to accusations 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. 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." Further information can be found at the following link:

http://www.bwea.com/pdf/briefings/lfn_summary.pdf

7. How noisy are wind farms?

People are usually surprised at how quiet modern wind turbines are.  It is possible to hold a normal conversation standing directly underneath a modern wind turbine and such noise as there is decreases rapidly with distance from the tower until blending into the general background.

Wind farm developers are required to carry out detailed noise assessments and comply with rigorous noise standards designed to ensure that the amenity of the rural community is protected. The best advice for anyone with concerns is to go and hear for themselves - a map of currently operational wind farms is available on the Renewable UK (recently renamed from British Wind Energy Association) website, or contact us and we can help you identify your nearest operational wind farm.

8. Do wind farms reduce house prices?

A small number of studies have been conducted to try and answer this question, and the results have varied greatly with no substantive evidence between a positive effect, no effect at all and a negative effect.

The CSE report states there is no evidence that a causal links exists between house prices and the proximity of wind turbines, and this is borne out by larger studies carried out on transaction data in the USA.

It goes on to say that  that  “in recent years, estate agents and surveyors have begun to accept that data on house purchases clearly show there is no lowering of house prices caused by wind turbines”.

9. How much support is there for wind farms?

Over the last 15 years more than 60 separate wind farm surveys have been carried out by different organizations, and a summary of these was produced by the sustainable development commission in their booklet ‘Wind Power in the UK'. The results have shown a consistently high level of support for wind farms with an average approval rating of between 70-80%. Levels of support have also been shown to increase after a wind farm has been built.

10. What is the future for wind energy?

The Sustainable Development Commission (SDC) and the Department of Business Enterprise and Regulatory reform (BERR) consider that wind energy is the most economically viable and scaleable technology and that it will be the key renewable energy technology out to at least 2020. In its Renewable Energy Strategy for the UK published on 15th July 2009, the Government suggests that renewables could provide more than 30% of the UK's electricity by 2020. The scenario presented for achieving this suggested that around 38,000 MW of renewable electricity generating capacity would be needed, of which  approximately 27,000 MW would come from onshore and offshore wind farms.

The National Renewable Energy Action Plan (July 2010) published after the Coalition Government came to power sets out that:

• the UK needs to radically  increase its use of renewable energy; and
• the UK Government believes climate change is one of the gravest threats we face,  and that urgent action at home and abroad is required