• News
• Sport
• Comment
• Culture
• Business
• Money
• Life & style
• Travel
• Environment
• Blogs
• Video
• Jobs
• A-Z

Tidal power

High water

The future of energy may lie somewhere in the sun, the skies and the moon. Solar and wind power use established technology but both have their problems: Britain is too cloudy, and wind schemes, although necessary, are unpopular and unpredictable. Could the pale moon, and the tides it causes on earth, help? No country is better placed than Britain to draw energy from the seas. The tidal range here is among the greatest on the planet, and the islands and river mouths of the north and west coasts offer tempting sites where each day vast volumes of water move back and forth on cue (with the Pentland Firth, off Orkney, being described hopefully as "the Saudi Arabia of tidal power").

The potential has been obvious for years. The obstacle has been part financial, part technical. Tidal energy schemes are easy to design but very difficult and expensive to make work in practice. That is changing. In May, tidal electricity, from a small experimental scheme in Scotland entered the national grid for the first time; last week a larger underwater turbine in Northern Ireland also began generating power. That second scheme is important: producing 150kw, still a tiny amount, it aims to expand to 1.2MW once completed. That is not much compared to the eight big nuclear plants that Gordon Brown wants to see built, each producing 1,200MW (or even a single good wind turbine, at 2-3MW) - but nor does it come with such a cost as nuclear. Last week the bill for the clean-up of existing nuclear sites rose by £10bn to £83bn.

One attraction is that much of the technology - unlike for wind energy - is being developed in this country. A small firm in Hull, for instance, is heading the design of a big tidal scheme planned for South Korea. But a bigger appeal is that tidal schemes, unlike wind, produce electricity reliably, reducing the need to keep replacement sources on tap. They are also much less visibly intrusive than wind farms. That does not mean they are harmless: the biggest tidal scheme of all, if ever built, the Seven barrage, would have a huge ecological impact, and even smaller underwater turbine sites may harm marine life. But they could be installed with little public protest.

The first commercial schemes are now being developed. This month the French energy firm EDF announced it would build 3-6 turbines off the French coast; others are being planned off west Wales. The technology is still not certain: there are advocates of all sorts of variants of floating and fixed turbines, oscillating columns, even osmosis. But it will work, will be affordable and Britain is the best place in the world in which to use it.

Close