Oxford academics have pioneered tidal fence technology to harness the power of the sea in the Bristol Channel. In 25 years, tidal power might even account for 15 per cent of Britain's electricity supply writes Helen Massy-Beresford. 

Above: Tidal fence technology developed with Oxford engineers

By Helen Massy-Beresford

A combination of Oxford engineering know-how and lightweight carbon composite materials means a new tidal turbine being developed by Kepler Energy should soon be harnessing the power of the sea. 

The tidal fence technology in the Bristol Channel uses a rectangular format instead of the circular shape used for wind turbines, explains Peter Dixon (Corpus Christi, 1968),chairman of Kepler Energy, a private company which was spun out in 2010 through Isis Innovation. It exploits technology developed by three academics – Professors Guy Houlsby, Martin Oldfield and Malcolm McCulloch – at Oxford’s Department of Engineering Science and the University still holds a stake in Kepler Energy. 

Bristol Channel
Above: Kepler Energy is aiming to install a tidal fence, just under a kilometre long, in the Bristol Channel

'What the professors spotted is that the physics of operating under water is quite unlike the physics of working in air,' Dixon says. 'It’s much better to have a rectangular shape presented to the tide because you capture a larger area of water. The power output of these machines is probably two or three times higher than you would get from putting a series of propeller type machines in the same area.'

Dixon is confident the company will have the funding and permission it needs to have the tidal fence, which is just under a kilometre long, up and running by 2020-21. 

Professor Guy Houlsby, Professor of Civil Engineering at Oxford’s Department of Engineering Science and leader of the Tidal Energy Research Group is one of the academics who came up with the idea. He says the project has sparked broader research at Oxford into the potential of the tides. 

'The tides are a much more subtle resource than wind power. The larger part of my tidal group is working on understanding how we can exploit and quantify tidal resources and optimise their use.'

Severn Bridge
Above: Tidal barrage technology could one day be introduced to the Severn Estuary as well

The UK has some of the best tidal resources in Europe he says, estimating that tidal power overall could potentially contribute around 15 per cent of the UK’s electricity supply in 25 years’ time, with barrage technology, which could one day be installed in the Severn Estuary. It could account for around half that, and the rest could come from tidal stream technology, Kepler’s area of expertise. 'It’s not a magic bullet but it could be a useful contributor,' he says.

Image courtesy of © Shutterstock and Kepler Energy


By Phil Bowers

Any chance of getting some information on this? I am amazed how little there is in the article. It is not even clear if anything rotates in this system!