Sir – Mr John Hall suggests windmills are very effective and reliable (Letters, May 15).

Whatever planet Mr Hall is living on must have a constant wind that never fluctuates because on this planet the wind varies and amazingly sometimes never blows at all.

Mr Hall’s windmills will therefore not work if the wind is (a) not blowing fast enough (b) is blowing too fast or (c) is not blowing at all. Whichever way you ‘spin it’, the windmill is ineffective most of the time.

Mr Hall claims windmills are ‘clean’ yet each windmill needs approximately 30,000 tonnes of concrete in its base to stop it falling over and environmentalists can provide evidence that turbines affect wildlife, specifically birds.

Like most windmill enthusiasts, Mr Hall seemed to ignore my comment that they drive down house prices, by an estimated 40 per cent! I wonder has Mr Hall got a windmill in his back garden?

Jason Smith, UKIP Bradford Chairman, Woodlands Avenue, Queensbury