CLIVE Brown is correct in citing the serious problem of CO2 pollution, but not in his thesis that ''windfarm protesters have their heads buried in the sand'' (Letters, August 14).

The UK government rules that electricity suppliers must source 10% of their power from renewables by 2010. In the UK, some 20% of total CO2 emissions arise from power-station generation. The 10% target, when met, will consequently amount to only 2% of the overall emission. Some achievement.

The real culprits are the internal combustion and aero jet engines, particularly the latter. It has been estimated that a return flight to the US could power each passenger's car for a full year. A clean, fuel cell electric engine, fed on hydrogen, is one of the options we should be vigorously pursuing, not fooling around with very expensive wind turbine construction.

Re the UK 10% renewable target, Scotland already produces an excess of electricity, 13% of which comes from renewables, mainly hydro. The Scottish Executive aims to increase this to 18%. Logically, all future windfarms should be sited south of the border until the percentage is equalised. There is plenty of wind there, particularly in the Westminster area. Moreover, Scotland's unique scenery would be spared the spreading blight of government-sponsored windfarms.

Frederick Jenkins,

The Lodge, Burnton, Kippen.

Recent correspondence in The Herald and excellent articles in the Sunday Herald for August 15 have focused attention on the general problem of providing sources of renewable energy. None has, so far, referred to projects, aired over 30 years ago I believe, to build dams across the estuaries of the Severn and Solway. These were to be fitted with generators driven by the predictable flow of tidal water into and out of the lakes created behind the dams.

Neither scheme was pursued at the time, probably for economic reasons. The economics have now changed and the dams would possibly have the added benefit of controlling flooding behind them when the sea levels rise due to melting Arctic ice. They also have the advantage of using proven technology so that they could be built starting now, knowing that they would work as intended.

Wave and tidal generating proposals may not be fully proved for several years so the government must accept nuclear generators to fill the gap. Work on these should start now and increased research be put into disposal of nuclear waste.

Bill Scott,

23 Lynn Drive, Eaglesham.

IN my letter (August 14) the cost of bringing the power ashore to the mainland from a proposed windfarm on the Isle of Lewis is a capital cost of (pounds) 400 per installed kW. Perhaps this was not made clear enough.

The figures for power generation that the Royal Academy of Engineering produced are: expressed per pence per kilowatt hour, combined cycle gas turbine 2.2, new-build nuclear (including decommissioning costs) 2.3, pulverised coal steam plant 2.5, onshore wind 3.7 but 5.4 if the cost of standby generation is included for the days of no wind, and offshore wind 5.5 or 7.2 including standby. Windpower generation is not cheap.

Eric Flack,

70 Crawford Drive, Glasgow.