Nuclear power still inspires nameless terrors and, until recently, few western politicians dared to discuss it. They preferred to tilt at windmills or peddle visions of backyard power stations running on refuse. Useful as alternative energy systems - and conservation - may be at the margin, they cannot replace the need for big new power stations. As Sir David King, the UK government's chief scientific adviser, insists, that must include nuclear.

This vie­ reflects a global revival of interest in nuclear power, including in the US, where a nuclear moratorium has lasted almost three decades. Some 24 new reactors are now being built worldwide, mostly in Asia and eastern Europe. A further 41 are planned or on order, and another 113 are under consideration. In total, this would equal 40 per cent of the world's present nuclear capacity.