Inspired idea from the waters of the Nile

Peter Fraenkel, one of Britain's most respected pioneers of renewable energy, has been working on the idea behind the new tidal turbine for longer than 30 years and originally used the technology on the River Nile.

Trained as an aeronautical engineer, Dr Fraenkel joined the Intermediate Technology Development Group – inspired by E F Schumacher, the author of 'Small is Beautiful' – while working in Africa. He conceived the idea of "taking a windmill and turning it upside down" in 1976 as a way of using river currents to pump water to irrigate fields.

After first testing the turbine on a rig mounted on a motor boat on the Thames, he installed a current-powered pump on the Nile near Juba in Sudan, where it worked for years before the civil war caused the project to be abandoned. As concerns about global warming grew, he said: "It occurred to me that if the idea worked in rivers, it might work at sea."

He first tried it in 1994 on a raft moored on Loch Linnhe on the west coast of Scotland and found that – though the technology worked – the raft was continually shifting on its moorings.

He produced the Seaflow prototype, anchored to the seabed off Lynmouth in Devon, and then Seagen – only to be frustrated by delays in getting it operational, the latest of which was last week.

"We were beginning to think we were jinxed," he said last night. "The installation is not an easy thing to do and we are keeping our fingers and toes crossed over the weather. We're hoping all will go well and will see what happens."