As a result, the eminent biologist who runs the centre, Dr Robin Crump, was presented with a unique "before and after" study which is providing valuable information about the precise impact of oil on the life of the sea-shore.

BBC: News | UK | West Wales recovering from 'environmental disaster'

Now all 14 of its 'berths' - areas of sea connected by cable to the shore - are booked, a sign of growing interest in this fledgling source of power.

BBC: Tidal power gets a stormy birth off coast of Scotland

Above sea level, the offshore structure has been bolted together with a conventional offshore turbine of the sort used for near-shore wind farms that are bolted to the sea-bed.

BBC: Floating challenge for offshore wind turbine

Russia is rapidly developing the energy-rich Yamal Peninsula, on the eastern shore of the Kara Sea.

BBC: Russia explores old nuclear waste dumps in Arctic

Moreover, onshore production of floating turbines that are then towed offshore to be anchored in place should prove cheaper than the weather-restricted and costly off-shore construction of sea-bed turbines.

BBC: Floating challenge for offshore wind turbine