Tide-power generator rolls in on a wave

It is made of 800 tons of steel, and was launched yesterday on the river Clyde, but it is not a ship: Osprey, as it is called, is the world's first commercial power station fuelled by wave energy.

For Allan Thomson, managing director of Applied Research and Technology, in Inverness, the hollow 20-metre- high structure represents a substantial personal triumph over a government which has provided barely any funding for a project that is both environmentally friendly and, potentially, a huge export earner.

Osprey - which stands for Ocean Swell Powered Renewable Energy - is being towed to a site near Dounreay in northern Scotland. It should arrive there by Sunday, where its ballast tanks will be filled with sand to sink it 350 metres offshore.

There, it will produce energy from the ceaseless ocean swell: on average it will be able to generate an average of 2 megawatts, enough to power 2,000 homes. A wind turbine attached to the top of the structure will generate another 1.5 megawatts, which will all be fed back to shore by an undersea cable.

While this is small compared to onshore power stations, the seas around Britain could generate up to 12,000 megawatts. "We hope to get a provisional export order within a year, following trials in winter," said Mr Thomson, a former welding engineer.

"It will probably come from the Caribbean or America. But we have had interest from North and South America, China, India, New Zealand and Africa."

He added: "I think it will be a viable technology and that it will compete with power stations powered by fossil fuels."

The generator works by letting the swell compress and push air trapped in a half-submerged chamber, which Mr Thomson likens to "an artificial offshore cave", up through turbines to create electricity.

The cost per kilowatt-hour will be about 6p from the pilot plant, but he expects this to fall to 4p. This is expensive compared to many British generating systems but cheap compared to others in the US, where it could quickly pay for itself. The plant has an expected lifetime of 25 years.

The project has lasted five years and cost about pounds 3.5m, including free steel from British Steel. But it received just pounds 50,000 from the British government, for preliminary tests of a model in a water tank.

In March 1994, the Minister for Energy, Tim Eggar, announced that the Government would not fund any more research into wave energy, blaming its "limited potential to contribute commercially to energy supplies".

Mr Thomson said: "Like any new technology, wave energy needs a long time to become mature, and other energy industries have received significant funding. I hope that the Osprey will get the Government to review its position. But it's all tied up in politics."

Funding for wave energy projects has also been held up by government financing rules, which assume inflation will run at 8 per cent, and so in effect penalise systems with high capital costs and low overheads.

Instead the project has been funded by a combination of private and public money, including AEA Technology, Scottish Hydro Electric, the Highlands and Enterprise Network, GEC Alsthom, Cegelec of France, and the European Union's Joule programme.

One of the biggest benefits, according to Mr Thomson, is that once built, the plants can have a positive environmental impact, becoming artificial reefs which provide living space for fish and sea creatures. "We are talking to some people in the US about growing lobsters on them," he said.

Another possible benefit, if export orders take off, could be to revive a form of shipbuilding on the Clyde. Osprey took six months to build and larger versions could provide employment for construction workers for up to a year.