Electricity supply

While Les Reid’s letter yesterday in response to Prof Ponton (6 September), correctly identifies the severity of the problems facing Scotland (and the UK) in re-establishing a reliable and economic electricity supply, his proposed solution of building large hydro schemes cannot provider the answer.

A large hydro scheme requires a large catchment area at a high level (to collect sufficient water with significant potential energy) and there are almost no such areas remaining for development.

Indeed, it is already the case that nearly all the water that falls on high ground in Scotland already passes though several turbines on its way to the sea.

Even so, the total installed capacity of despatchable hydro in Scotland is some 1,400MW, which has to be compared with a peak demand in Scotland of some 5,000MW and ten times that in the UK.

But there is a solution which is economic, can be constructed reliably in some five years and of which we have had over 50 years of satisfactory experience – and that is nuclear.

But there is nuclear and nuclear. Any engineer with experience of constructing and operating our nuclear power stations would have ruled out the French design proposed for Hinkley C even before the tender stage – the evidence shows that it cannot be built to time and the costs to consumers would be unacceptable – unlike our existing stations at Hunterston and Torness which were built to time and produce lowercost electricity than even the 2,400MW Longannet burning Scottish coal.

This is not the time for gambling on our energy future; we need proven and reliable generation and this is available in the shape of the Westinghouse APWR and the GE Boiling Water Reactor, proposed for sites at Sellafield and Anglesey. Westinghouse was sold off by the Blair government to the Japanese and the APWR is now being built successfully in large numbers throughout the world; while the GE reactor also has a good record.

Indeed, it is vital with an economy of the size of the UK that we concentrate our resources and expertise on a limited number of designs rather than adopt the scattergun approach of the Cameron/ Osborne era which repeats the errors of the early years of our nuclear development when government insisted, in the name of competition, on no less than five contractors and designs.

The Theresa May review will do well if it recognises these facts. Government should facilitate the construction of these projects by guaranteeing the funding and perhaps even by participating directly in the financing. The profits will then accrue to the UK taxpayer rather than to foreign governments.

SIR DONALD MILLER Former chief engineer, North of Scotland Hydro Electric Board, former director of engineering SSEB/ Scottish Power

Les Reid is correct in that UK energy provision, whilst driven by politics rather than scientific principles, is chaotic, particularly in Scotland. However, I would question his suggestion that building more hydro dams would do much to alleviate the disastrous situation we will soon face.

Direct hydro power depends on rainfall, catchment area and the height of this above sea level. I did the fairly simple calculations some time ago which, as I recall, showed that we could no more than triple our current very modest performance, ie, to about 5 per cent of UK present needs.

Norway, because of topography, climate and very low population density, is in fact the only European country which has sufficient hydro power. Our secondary, or pumped storage hydro, as Professor Pontin (Letters, 6 September) has pointed out is of insignificant magnitude and could again only be about tripled (at enormous expense) and of course needs a sufficient and reliable pumping system from some other primary energy source.

There is only one non carbon energy source of sufficientpotential and on-demand reliability to satisfy our needs. Nuclear, unfortunately, has been banned in Scotland because of rather irrational safety fears.may I point out that as many people lost their lives in providing our modest little hydroelectric installations as perished in the Chernobyl accident – but for Aberfeldy hospital I would have been amongst that number.

All forms of country-sized energy production carry risk.

The experience of, as I recall, about 1,500 reactor-years of operation, including Chernobyl, has shown that nuclear is in fact the safest.

DR A MCCORMICK Kirkland Road Dumfries