A Few Facts about Wind Turbines.
For those who think that wind farms are green and environmentally friendly have a look at this 6-minute video about wind turbine construction.
Here are a few facts on wind power sent to us by David Bellamy in UK:
• Wind farms generate cheap (or even free!) electricity
This is not true. The electricity generated by wind turbines is much more costly than that from conventional power stations, because the price has to include enough to cover the subsidies paid to the wind farm companies for operating them. UK electricity prices have already gone up, and are predicted to go up by a further third over the next decade, to pay for our commitment to renewables.
• Wind power is reliable because the wind is always blowing somewhere
That is not the case. Meteorologists can list many periods, often in very cold winter weather, when there is so little wind that the contribution to the grid is negligible. In addition, wind turbines only start generating when the wind is blowing at about 10mph, and have to be turned off for safety reasons when wind speeds reach about 55mph. In fact, on average, for about 110 days a year any individual turbine may generate no electricity at all. That means a back-up supply always has to be available – which is why no countries have been able to shut down their conventional power stations.
• Wind farms provide employment
This is hardly true. There may be a small number of construction jobs on offer while the access roads to the site are being built but the on-site work to erect the actual turbines is a specialist job that will only be carried out by the contractor. Once the turbines are up, wind farms are operated remotely, sometimes even from abroad, so no ongoing local jobs are likely.
• Wind farms only last for 25 years and are then removed
The key components of the turbines, namely the gears, normally last only about 10 to 12 years before they need replacing. Very few wind farms are as much as 25 years old yet – but we know of several cases where the operators have taken the opportunity to rebuild much sooner than that, erecting larger turbines than originally installed. So it is safer to assume that a wind farm, once built, will effectively be a permanent feature of the landscape.
• Wind farms are not noisy
Wrong. There are plenty of examples where residents have suffered ill health effects caused by both noise (and on occasion shadow-flicker) when living too close to turbines. Some people, including some farmers, have even been forced out of their homes as a result. There is no legal setback distance from homes in the UK, though the Scottish Executive recommends 2kms as a desirable minimum.
• Wind farms generate hardly any complaints
A report by the University of Salford in 2006 showed that about 20% of wind farms had already generated formal complaints. That work is currently being updated, as there are many more wind farms today than in 2006 and their technology has allegedly improved. The current work shows that the 20% level of complaints, however, remains steady.
• Wind farms don’t cause a fall in house prices
Wind farm developers make this claim but there are certainly cases where people have difficulty in selling their homes once turbines are present. In one case, the vendors were legally obliged to compensate the purchasers by 20% of the house value, plus interest, for selling without having disclosed the presence of a wind farm proposal. The Royal Institute of Chartered Surveyors surveyed house values near wind farms and found that about 60% had declined by amounts varying between 5% and 50%.
• Wind farms have no damaging effect on tourism
The earliest wind farms had such novelty value that they were almost tourist attractions in themselves – but even the developers admit that this no longer applies. One caravan site near Harrogate, for example, has seen a drastic drop in income since four turbines were erected nearby. The Campaign for the Protection of Rural England, has recently released a ‘Tranquillity Map’ of the UK because it is clear that tourists are increasingly looking for peace and quiet when they go away from home.
• Wind turbines pose no danger to birds and bats
Not true. Small birds can often avoid rotating blades at short notice (though remember that the tip of a turbine blade is moving at about 200mph) but larger birds such as eagles have much more trouble in diverting to avoid them. Birds that fly around at dusk or during the night are far more at risk than daytime birds. Bats are affected in a different way: They are seldom hit by the blades but they can suffer what is known as ‘barotrauma’ where the change in pressure near the blade tip kills them by damaging their lungs.
• Wind farms are a safe form of technology
On the whole this is true (though there may be adverse health effects as noted above). Accidents can happen, however; there have been some examples in Britain of blades collapsing or flying off, and one or two cases of turbine hubs catching fire. A different concern is ‘ice throw’ which happens when ice forms on the blades, usually overnight, and may be flung off in chunks when conditions warm up. This may be a particular concern for farmers with livestock.
• Lines of pylons are needed to take the power away from the site
This is not true. Typically, the cables are laid underground from the turbines within the wind farm site and are then linked to overhead lines on wooden poles to connect with the Grid. One worrying aspect, though, is that the developer of a wind farm does not have to seek planning permission for connection, or even to indicate what the proposed route for connection will be, because that is a matter for the Regional Electricity Supplier to address. Permission to the RES is more or less automatic.
• Wind farms reduce CO2
Wind farms contribute very marginally to reducing CO2 mainly because an alternative power source has to be kept running at all times for the periods when the wind stops blowing. If we were to rely entirely on wind, we would need to learn to live with a very uncertain and intermittent electricity supply!
• Well at least wind farms are better than nuclear power stations
Maybe. It would take about 6000 wind turbines, spread over perhaps 40 square miles to produce as much electricity as the one coal-fired power station at Ferrybridge, or nearly 3000 turbines, spread over 20 square miles, to match one of the two nuclear reactors at Hartlepool. But in both cases the power stations would still be needed as back-up for the 110 days when all those wind turbines would produce no electricity at all.
Finally, some Good News:
The price of carbon credits on the Chicago Carbon Exchange has collapsed to 5 cents a ton and the exchange has decided to cease trading.
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