Michael Kelleher from Dundee (May 25) reckons that if we look in almost any river at this time of year we are likely to see a dried-up riverbed. I haven't seen the state of the Tay recently, but I can assure him that on the west coast the burns and rivers are providing an impressive spectacle of white water pouring, for the most part uselessly, towards the sea. This past winter I have seen the most intense and prolonged deluges I have ever experienced in over 50 winters.

His other point, that hydro has a profound impact on the ecological and environmental wellbeing of the locality is unarguable, but, then, the radioactivity of the beaches and waters around Dounreay and Sellafield also has a profound impact.

The hydro programme of the 1950s was an incredibly far-sighted investment in the future energy needs of Scotland and I earnestly hope that our current crop of politicians has the same ambitious vision. An expansion of the hydro scheme makes absolute sense, whether large-scale dam or run-of-the-river. Fast-tracking tidal and wave-power energy also makes sense.

The profound impact of the hydro programme was human, in cleared glens, as well as environmental but the legacy has been a secure energy source and recovered eco-systems (how does a beach or a local community recover from radioactive particles?) The people who keep saying: "No, we shouldn't do this" should be made to add: "This is what we should do instead." It's far too easy to be casually negative without suggesting alternatives.

Sandy Slater, 19 Lorn Drive, Glencoe, Argyll.

It's sad that the best Gerry Carlton (May 26) can do to extol the virtues of nuclear power is to try to imagine that if Alex Salmond put a wind turbine on his house "on average, it will produce half the power needed to boil a kettle in the dark".

Is it likely that "half the power needed to boil a kettle" will be the total power produced over the lifespan of the turbine? Or maybe just every year? Anyway, no doubt it would take weeks to get the device up and running at a working speed. And, of course, there's the well-known variability of wind which makes it so unsuitable. Just when Alex was standing by with the milk and sugar, the water would probably go cold again.

It is so blatantly obvious that opponents of renewable energy are just not capable of lateral thinking. The problem with using a variable power source such as wind energy lies in its storage, and the option most often mooted is pumped hydro. Of course, a larger grid of wind turbines spread over the country would tend to obviate the problem, since when one part of the country is calm, another will tend to be windy. A domestic turbine would likely be used to charge a battery and/or heat water.

I would refer doubters to Troen and Petersen's map of wind energy resources in Europe to see if they think they still need uranium plants to electrify the country. We hear constantly of how nuclear power is "clean" but, of course, it is not. Uranium still has to be mined and transported over long distances (often from Australia).

Large power stations (likely terrorist targets these days) have to be built and, at the end of the power cycle, the still-dangerous waste is basically "swept under the carpet". Of course, like all power stations, wind turbines consume energy in their production, but in operation they emit no toxins, acids or greenhouse gases.

Barry Lees, 12 Denholm Street, Greenock.