A pioneering plan to create power from the waves suffered a major setback last night when the machine capsized off the north Suffolk coast.The seabed off Southwold was being used to test a new way of harnessing power from the waves which could ultimately generate electricity on a large scale.

A pioneering plan to create power from the waves suffered a major setback last night when the machine capsized off the north Suffolk coast.

The seabed off Southwold was being used to test a new way of harnessing power from the waves which could ultimately generate electricity on a large scale.

But as the experimental wave generator, weighing 80 tonnes, was being towed into position on a floating pontoon yesterday, the pontoon capsized. Local shipping had to be warned as the 18 metre (59ft) high generator was floating loose and drifting with the tide.

It was later connected to one of the tugs which had been towing the pontoon and towed to a safe location at Dunwich Bay, near the beach, where it was out of the way of shipping.

The drama unfolded at 12.30pm as it was being towed into position by two tugs. For reasons which are still not clear, the pontoon capsized, dumping its expensive cargo into the sea. None of the crew were hurt. It was not clear whether the machine itself was badly damaged or whether it will be able to be salvaged and put up as planned.

The wave energy machine was being put in place five miles off Southwold for a year-long sea trial, which was intended to gather detailed information on how the machine performed. It is planned as the forerunner to full-size wave farms which could power 60,000 homes.

Mario Siano, watch manager at Yarmouth Coastguard, said: “We are pleased to say there were no injuries sustained to any of the crew on board. There were no pollutants on board. The tugs remain on scene until a salvage operation is put into place.

“All appropriate authorities have been informed and the Maritime and Coastguard Agency counter-pollution officer is aware and is monitoring the situation.”

Southend-based Trident Energy and their wave energy plans were featured in Leonardo Di Caprio's eco-documentary, The 11th Hour, and were described last year by energy and climate change minister Lord Hunt as “a very exciting project by Trident”.

When the test model was unveiled in Lowestoft earlier this year, company founder Hugh-Peter Kelly said: “It's our aim to crack wave energy…We want to prove to the world that this works, and that Trident can produce grid-ready AC electricity.”

The machine's inventors say its strength is in its simplicity. No hydraulic equipment or air compression is needed and there are few moving parts. The machine stands on a giant pair of legs, supported by submerged pontoons anchored to the sea bed, to hold it above the waves. The framework for the machine has been built by Lowestoft marine engineers Small and Co.

Special floats move up and down with the waves to drive generators, which convert the motion into electricity. Special sensors to detect stormy conditions pull the floats up automatically and protect them from serious damage until the danger has passed.

Trident Energy could not be contacted last night.