Revamped Osprey is set to sail again

Wave-power pioneers hope for success second time around

Osprey, the sea-based generator intended to harness power from the waves, which sank off the Scottish coast at its 1995 launch, has been redesigned and could be relaunched next year.

A second version of the Ocean Swelled Powered Renewable Energy machine is about to go into production, said Inverness-based Applied Research & Technology, which coordinates the EU-sponsored project.

Osprey 1, a 2MW wave generator – with enough capacity to power 20,000 homes – cost £7m to build, after five years in development from 1990.

It was destroyed while it was still being stabilised in the Pentland Firth off Dounreay, Caithness, following a massive swell.

The 850 tonne unit suffered holes in two of its nine ballast tanks, which are filled with sand and water to keep it in position on the seabed.

Although fully insured, the company salvaged the turbines and generators from the sea.

The ballast system has been improved and the efficiency of the turbines – driven by air expelled from the rising of waves captured in an oscillating water column – has been improved by remodelling the blades using supercomputers.

Opsrey works by trapping the swell of the ocean inside its collector vessel. As the swell rises and falls inside the collector, air is pushed out and sucked in through the top of the structure, turning a Wells turbine. The device connects to a generator which feeds the Grid.

A 500kW wind turbine has been added on top of the wave generator, to give a total output of up to 2.5MW for transmission to shore by submarine cable.

Other project participants along with Applied Research & Technology are Scottish Hydro Electric, British Steel, Cegelec and Cegelec Projects of France, GEC Alsthom and the Atomic Energy Authority.