From: Thomas Sheriff, Nettleham Road, Lincoln.WITH regard to the letter from Mark Gregory (Yorkshire Post, June 24), the major problem with all wind turbines is their unreliability. Being totally dependent on the variations of the wind, they can only generate useful amounts of energy within a relatively narrow band of wind speeds. A good example was on a very cold day last December when the demand on the system was 58,000 megawatts (MW). The possible declared output from more than 2,000 wind turbines was in excess of 1,800MW; the amount that was actually generated by wind power was no more than 36MW – less than 0.06 per cent of the total load demand on that day.They are also very expensive to maintain, requiring the erection of very expensive scaffolding and they are, for this reason, subsidised by the Government to approximately £250,000 per wind turbine per annum. By contrast, nuclear power stations do not receive a subsidy. Last year, in Denmark, two wind turbines were totally destroyed when they could not be stopped in a high wind. Technicians sent to resolve the problem had to run for their lives when the structures collapsed.They are also prone to lightning strikes and there was a case in Japan where more than 50 wind turbines were damaged, several beyond repair, when the blades sheared off in high winds. Only a few months ago, in Lincolnshire, one machine was put out of action because of blade fatigue.
