Good tidings

A semi-submersible tidal power generator based on wind energy technology could allow the UK to meet a significant chunk of its electricity needs from deep coastal waters, according to engineers working on the project.

The TidalStream system, which has already been tested in the Thames, would harness power from the fast-flowing waters found at depths of 40m or more, where an estimated 63 per cent of the UK’s tidal energy resource is estimated to be.

Most tidal energy initiatives focus on shallow waters, which are technically less challenging to tap into, but yield far less power. Tides in the 60m-deep Pentland Firth off the northern tip of Scotland, for example, generate water flows of up to three million tonnes/sec, and tidal speeds averaging 1.5 to 2.2m/sec — some of the fastest in the world. By harnessing this, TidalStream believes this single location could supply five per cent of the UK’s electricity demands.