CLIMATE change is in the news again (Echo, Aug 17). Some people still believe that it can be avoided by covering the countryside with wind turbines.

But there is nothing new about climate change.

There have been ice ages in the past and there have been warm periods. The climate is driven by variations in the earth’s orbit, the sun’s cycle of activity, the oceans and volcanoes. The Romans were growing grapes as far north as Hadrian’s Wall and some glaciers disappeared, only to re-appear later. The vikings grew barley and wheat and raised cattle and sheep in parts of Greenland that are now uninhabitable.

The so-called Little Ice Age followed. There was famine, disease and depopulation. Ice fairs were held on the Thames until the 1820s. The little Ice Age ended in 1850 and there was warming from 1860 to 1880, cooling from 1880 to 1910, warming until 1940, cooling to 1976, warming from 1976 to 1998 and now slow cooling to the present day.

Electricity supplies from wind turbines go up and down as wind speeds change so expensive backup gas fired power stations haveto be used to maintain supplies to customers.

Frequent changes in output result in the back-up power stations burning gas very inefficiently so they use almost as much of it as they would if they were generating electricity normally with wind turbines switched off. In a nutshell, hugely expensive and visually intrusive wind farms do not significantly reduce man-made CO2 emissions – if at all.

The earth’s climate has always gone through periods of change, long before mankind was on the scene, and wind turbines have a negligible effect on the CO2 content of the atmosphere.

The time has come for the Government to admit that generating electricity from wind farms has been an expensive mistake.

James Allan, chartered fuel technologist, Hartlepool .