IN RESPONSE to Professor Anthony Trewavas (Debate, 11 March) may I point out that power provision in Scotland is not a devolved option so the Scottish Government can control it only in a negative way through planning permission which, as he indicates, it does with gusto.
There are a number of things which Holyrood either does not realise or, more likely, chooses to misrepresent for purely political purposes. First is the oft-stated claim of 100 per cent renewable energy by 2020. This actually refers solely to electrical energy which happens to be only 18 per cent of Scotland’s power usage.
Secondly, wind turbines have a life of only 25 years so soon we will be faced with starting a multi-billion pound waste disposal and renewal programme which no-one seems to have addressed.
Thirdly, we do not actually produce energy. What we do is energy conversion, which is not a 100 per cent process. The much-vaunted pumped hydro is not a means of producing energy but, being a three-stage process (source to electrical energy to pumped storage to output electrical energy), a means of rapidly consuming it and is useful only as a means of energy management.
If we could get a reliable 30 per cent of wind turbines working simultaneously (the usual most optimistic claim) then, at 70 per cent conversion for each of the remaining two stages on an on/off 50 per cent cycle we would require 3,000 land turbines to produce 1 GW of “direct” consumer-usable electrical energy and 1 GW of pumped storage energy. However, the uncertainty of wind power means that back-up equivalent to the required 3 GW would still be needed. A 2 GW nuclear system coupled with pumped hydro would produce the same result for at least 50 years without this back-up, at a fraction of the cost and with a fraction of the required expensive and unsightly distribution network.
Scotland’s total electrical requirements would be almost entirely satisfied by only three such systems together with existing “conventional” hydro installations. A bit of marine power on top would do the rest. Who needs wind, which was more or less abandoned in the 19th century, as a reliable energy source? Does Mr Salmond, with his usual bravado, really want Scotland to “lead the world” in this direction?
Dr A McCormick, Dumfries