Wind turbines were very expensive years ago when first mooted as a viable source of electricity. Over the years, however, costs have fallen, and proponents argue that these devices provide power in a cost-effective and environmentally-friendly way.
They use an inexhaustible supply of energy constantly renewed by radiation from the sun, whose exploitation has none of the unpleasant side-effects commonly associated with the extraction of power from fossil fuels.
In addition, the enthusiasts say, land on which wind turbines are located can still be used for other purposes - for growing crops, for example, or for grazing sheep. And if the machines, for some reason, must some day be removed, no environment damage or unwelcome residues remain.
But there is, as always, another angle to the story. The nightmare scenario was graphically illustrated in the Dustin Hoffman and Tom Cruise film Rain Man, which featured panoramic views of a desert landscape peppered with a veritable forest of spinning wind turbines. The scene was the San Gorgonio Pass near Palm Springs, California, which hosts the third largest concentration of wind turbines in the United States, comprising well over 3,000 power-generating units.
The wind turbines of the San Gorgonio Pass were installed much closer together than they are in modern arrays, which tend to be well spaced out so one machine does not interfere with the wind blowing towards another.
Nonetheless, the scenes from Rain Man reinforce the point that wind energy is highly dispersed and diluted; it takes several hundreds - or as in this case, even thousands - of windmills to extract the same amount of energy from the wind as that produced by a single traditional power station. And a wind farm of several hundred machines will occupy a very substantial area and inevitably have a significant visual impact.
Unfortunately, too, the most suitable locations for wind farms as regards the availability of wind, are often those in the most scenic parts of any region - in Ireland's case along our western and northwestern seaboards.
Wind farms undoubtedly obtrude. But the other objections to their presence are not so convincing. Noise pollution is sometimes suggested, but modern turbines, we are told, are no more noisy than a car travelling at 50 m.p.h.; in an unpopulated area, this does not seem excessive.
There is little evidence to substantiate fears that damage to bird-life is a major problem. And alleged interference with radio signals can be eliminated by blades manufactured from suitable synthetic materials. But this, of course, increases costs - and so the argument goes on.