Developed by British tidal energy company, Marine Current Turbines (MTC), the 'SeaGen' turbine works like an underwater windmill. More predictable than wind or solar power, the UK government has set up a £42 million Marine Renewables Deployment Fund to help firms develop these projects.

Situated in Strangford Lough in Northern Ireland, gravitational attraction of the moon creates some of the world's fastest tidal flows at speeds of up to 8 knots. A farm of turbines off the coast of Anglesey, north Wales, is expected around 2011/2012.

"Marine power has the potential to play an important role in helping us meet our challenging targets for a massive increase in the amount of energy generated from renewables," says secretary of state for business, John Hutton.

Strangford is a breeding ground for common seals but MTC says the turbines are unlikely to pose a threat to marine wildlife with rotors turning no more than 10 to 15 revolutions per minute. Turbines are also less damaging than constructing dams to harness tidal energy.