What is very clear that on days like this Midwinter's Day, when at noon no electricity at all was being produced by wind and little during the whole of the preceding week, the French interconnector, which derives much of its power from nuclear plants, made a greater contribution to our energy supply than wind did. In fact, it quite often exceeds the combined total of wind, hydro and pump storage sources.
The backbone of our energy supplies comes from coal, oil and gas. Scotland still has abundant supplies of all and indeed huge reserves of low-sulphur coal.
Since we only produce around 0.2 per cent of world carbon emissions and are more than self-sufficient in energy, the only thing we have to worry about is wasting time, money and energy in building wind farms that we cannot depend on. No doubt, however, we can continue to depend on ingenuous and ingenious huffing and puffing from the wind lobby.
Blair Atholl, Perthshire
The statements by Jim Mather that Scotland does not rely on energy imported from France, and that we are a net exporter of energy, is reassuring. It would be surprising if this were not the case in view of the fact that Scotland is not grossly overpopulated and is unique in western Europe in having an adequate source of energy, continuously available, of solar origin.
However, the minister's assertion that Scotland's self- sufficiency in energy production depends on the development of technology to dump underground excess carbon dioxide produced by human activity seems commercially motivated.
It is ecologically undesirable to shunt excess carbon dioxide from one part of the biosphere to another. This could create a problem for a future generation.
DR DAVID PURVES
Jim Mather is correct to point out that, as a net exporter of electricity, Scotland could hardly be importing electricity from France. However, it is deceptive to claim that 27.4 per cent of Scotland's "electricity needs" came from "green energy" in 2009. For all anyone knows, all electricity from renewables in Scotland is exported.
It IS self-evident that output from wind farms varies, which is why we will need a mix of renewable electricity generation – including onshore and offshore wind, hydro, biomass, wave and tidal power – and thermal generation for many years to come. Wind power is increasingly cost- effective and every unit of wind power displaces generation from other plant, thereby reducing carbon emissions
As with any "average", wind output will at times exceed the annual average of 30 per cent capacity and at times it will be less than this, but the pattern is similar each year and well understood by National Grid and Ofgem, with the regulator's independent experts stating that a growing proportion of renewables in the system is the best option for both energy security and costs for consumers in the medium term.
Over the last few weeks Great Britain has been importing electricity from France, but the headline "'Green' Scotland Relying on French Nuclear Electricity" (27 December) was conjecture, given that at no point did the article clearly demonstrate that Scotland was importing power during the period referred to.
With renewables contributing over a quarter of Scotland's electricity needs, reducing emissions and securing employment and investment opportunities, it is not so much our industry's credibility that is under threat as that of the minority who will use spurious technical arguments to prevent wind farm developments in their area.
Director of Policy
Bath Street, Glasgow