IT Power and other major marine energy players lobby for a Severn Tidal Fence instead of a Severn Barrage

A “Tidal Fence” would provide 1.3GW of Power and keep ports open

IT Power has grouped with  AMEC, BMT Group, Econnect, Edinburgh University, Marubeni Europe, NaREC, Pulse Tidal and others to form the Severn Tidal Fence Group (STF Group) to promote the idea of a ‘tidal fence’ in the Severn Estuary.

STF Group is lobbying Parsons Brinkerhof, the company undertaking the Government’s feasibility study into tidal power on the River Severn, to include a possible tidal fence as an alternative to a barrage.  A tidal fence would leave open major ports that might otherwise be forced to close if a barrage is built across the river. A tidal fence would also have significantly less impact on wildlife and reduce flood risks. 

A tidal fence is a continuous line of underwater tidal current turbines, installed in a way which forces as much flow to go through the turbines as possible. The STF Group believes this approach can offer a compromise between the interests of conservation, clean power generation, and the existing commercial interests in The Severn.

The STF Group’s preliminary investigation into a tidal fence in the same area as the proposed Weston–Cardiff barrage shows a fence would have a capacity of 1.3GW, or slightly more than Sizewell B nuclear power station, and provide around 1% of the country’s electricity supply.

Importantly, the fence would allow shipping to pass through and so keep the ports of Cardiff and Bristol open, whereas the barrage risks their closure.

The fence also allows the migration of salmon, and it would only slightly reduce the areas of mudflats which are an important habitat for migrating birds.  It would also reduce high tide levels upstream enough to significantly reduce the risk of flooding.

IT Power is working with Pulse Tidal on the development of tidal current devices and is currently installing a grid connected tidal generator in the Humber Estuary.