As with anything new, a small proportion of the population will be suspicious of emerging technology and wind turbines, despite being green and clean do not escape this. Below are some of the common myths I often come across when hosting public exhibitions for new wind energy proposals and the facts in response.
1) The energy taken to build a wind farm is never “paid back” by the energy produced
Figures for pay back times vary depending on the turbine and wind speeds. A report by Milborrow, ‘Dispelling the Myths of Energy Payback Time’, as published in Windstats, vol 11, no 2 (Spring 1998) gave an average figure of 3-5 months and a more recent study of the 2 megawatt Horns Rev wind turbines in Denmark by The World Steel Association gives a figure of 9 months. The average life of a wind farm is 25 years.
2) Wind turbines are not helpful in the fight against Climate Change
The US is the biggest emitter of carbon dioxide with an annual figure of around 6 billion tonnes and the UK is the 8th biggest emitter (data collected in 2007 by the CDIAC for United Nations). Power stations are one of the biggest carbon emitters so we need to find alternative ways of generating electricity whilst producing less harmful gases.
The production of electricity from wind turbines is clean and sustainable. Wind energy projects in operation do not create harmful greenhouse gases such as carbon dioxide or waste products unlike other conventional sources of electricity generation. Wind turbines generate electricity that would otherwise have been generated in power stations, thereby offsetting carbon emissions. How much carbon is offset depends on various factors including the type wind turbine and the type of power station the electricity might otherwise have been generated in. Current figures approved by the UK Advertising Standards Agency for carbon savings are very conservative but are probably the safest to assume at 4000 tonnes carbon dioxide per year per turbine.
3) Wind energy is much more expensive than conventional fossil fuels and nuclear
A 2005 report by the Environmental Change Institute at Oxford University predicted a small increase in the cost of electricity likely to result from wind power development – equal to around 2.5% of the average domestic cost of electricity with 10% wind power.
4) Wind turbines only work 27% of the time and are inefficient
A modern wind turbine has the capacity to generate around 2000 kilowatts (kW) or 2 Megawatts (MW). A 2 MW wind turbine will however generate around 30% of this maximum theoretical capacity resulting in around 5256 Megawatt hours (MWh) generated per turbine per year. On this basis a wind turbine will generate enough green electricity for the average annual needs of around 1100 homes, using an average demand of 4700 kWh per house based on electricity consumption figures from Digest of UK Energy Statistics. Wind turbines usually operate 75-90% of the time – but not at full capacity.
5) Wind energy does not save carbon emissions because back up power stations need to be kept or built and the grid cannot cope with the fluctuations in supply
A report by the Environmental Change Institute at Oxford University described the potential impacts of the variability of wind energy generation upon the UK electricity network. It reported that:
• The development of wind power will result in a reduced need for conventional capacity – with wind power supplying 10% of UK electricity, around 3GW of conventional plant could be retired;
• The cost of balancing wind power variability is expected to reduce with improvements in wind power forecasting techniques
A report from the UK Energy Research Centre ‘The Costs and Impacts of Intermittency: An assessment of the evidence on the costs and impacts of intermittent generation on the British electricity network’ (2006) states that ‘it is unambiguously the case that wind energy can displace fossil fuel-based generation, reducing both fuel use and carbon dioxide emissions’. There is no need to provide dedicated “back-up” capacity to support individual generators.
6) We should be looking at energy efficiency, marine, tidal and solar energy instead of wind energy
People need to use energy much more efficiently and there are many small actions you can take to do this such as boiling less water in the kettle and using energy efficient light bulbs. However this is not enough on its own. All renewable energy sources provided 4.98% of the electricity generated in the United Kingdom in 2007, 0.43 % higher than in 2006. There is however a huge energy gap that needs to be filled as fossil fuels run out. Renewable energy cannot fill this gap on its own but it certainly has to be part of the solution.
Wind energy is a fundamental part of the energy mix and it is playing an increasingly important role in renewable energy generation across the world. It would be disastrous to prevent the build out of technologies such as wind energy that offset harmful gases and are financially and technically successful. Notwithstanding this more funding should be put into the more expensive technologies such as marine and tidal energy and micro-renewables to try and find solutions to the technical and capital cost issues that are currently preventing their roll out.
In terms of solar energy, the technology is much more suited to the domestic scale market for hot water heating and countries with more hours of sunshine such as the US. The UK has the largest wind resource in Europe – it is completely logical that wind energy is utilised as the key renewable energy source. In countries where there is good potential for any of these technologies – as much should be utilised as possible.
7) Only offshore wind energy is viable
Offshore wind usually has a higher potential capacity factor due to higher wind speeds out at sea. However there are negative aspects such as ‘out of action’ timescales being longer due to the need for vessels to get out to the wind turbines and greater electrical losses due to the increased lengths of grid connection. On this basis it should not be automatically assumed that offshore turbines will generate more electricity. At almost double the price of on-shore wind, and with large projects involving huge capital sums, investors are usually more cautious about funding offshore wind and so strong government support is necessary.
As with different kinds of technologies we also need both on and off-shore wind technology to help fill our energy gap.
8 Wind energy projects harm house prices
The evidence base in the US shows the opposite. House prices close to wind farms in some areas rose at a higher rate than the regional average. In the UK the evidence is not sufficient to come to definite conclusion, however what we can say (and indeed the Royal Institute of Chartered Surveyors say) is that from the research carried out so far, wind farms do not appear to have any discernable impact on property prices and that other variables have more of an impact.
9) Wind farms kill birds and other animals
The RSPB in the UK supports a significant growth in offshore and onshore wind power generation.
A leaflet put together by the RSPB says that many species could lose their habitat to climate change – resulting in a huge drop in the number of birds. Moreover, a recent report published in the journal Nature confirmed that the greatest threat to bird populations in the UK is climate change For this reason they are supportive of wind energy. If wind farms are not located in areas used by birds prone to colliding with tall structures, impacts should be very low.
Poorly sited old wind farms have however caused some major bird casualties in Tarifa and Navarra in Spain, and the Altamont Pass in California. There are specific reasons why these wind farms are unusual including the use of steel lattice towers at Altamont Pass (where birds may try and nest). No environmental impact assessment was carried out, the wind farm comprises 4000 turbines and is in an area important for a number of birds of prey.
Wind farms can be kept away from bat flight routes and impacts on other animals and plants are virtually negligible as long as habitats are avoided. You don’t have to dig up a badger set to install a wind turbine – just move the turbine foundation to a safe distance.
Overall wind energy projects usually enhance habitats for protected species by providing some extra funding for schemes such as hedgerow restoration.
10) Wind farms are noisy and cause ill-health
Wind energy operation does not cause harmful emissions, pollutants or waste products. In response to the occasional unsubstantiated press or website post that wind turbines emit high doses of 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.”