ENGINEERS from Hampshire have been appointed to help design a scheme to generate electricity from the powerful tides of the river Severn.

Giffords, based in Woodlands, near Totton, has been selected by offshore energy specialist VerdErg to provide engineering and cost estimation support for its proposed Severn tidal fence scheme.

Scientists have long dreamed of harnessing the power of the huge 15- metre tidal range of the famous river, which divides Wales and England, but despite the energy on offer, the proposals have been dogged by environmental concerns.

An alternative to the traditional proposals for barrage schemes that block the river, the fence makes indirect use of the powerful currents flowing up and down the estuary. An array of vertical and horizontal tubes exploits pressure differences to drive water at high speed through the horizontal connecting tubes to generate electricity, rather than use tidal power directly to drive turbines.

The design means that water flows normally, reducing the impact on the river habitats either side of the structure, one of the biggest potential objections to barrage designs.

VerdErg estimates that the tidal fence will produce 80 per cent of the power of a barrage but for two-thirds of the capital cost, with “vastly reduced” environmental impacts.

The idea has won funding from a range of authorities, including the Government and the Welsh Assembly.

Nick Clarke, technical director at Gifford, said: “This design has the potential to be used at many tidal estuaries such as the Mersey, as well as the Severn. It is also likely to be ideal for micro-hydro power generation on inland rivers and for openwater offshore installation. It is a very exciting development.”

Gifford has been involved in a succession of high-profile projects, from the so-called Blinking Eye Millennium Bridge in Gateshead to the bridge across Poole Harbour and Southampton’s proposed Heritage Museum.