Tide turns for sea power

Using tidal stream (ocean current) and tidal range technology the UK could supply at least 10% of its electricity (around 5% from each).

The Sustainable Development Commission has just published its long-awaited report on tidal power and this is its conclusion.

It says: "Such a substantial prize deserves very close attention as part of much wider action aimed at tackling the twin challenges of climate change and energy security", the goals of the Energy White Paper.

It says a barrage in the Severn Estuary could supply 4.4% of the above total (17TWh), generating electricity for over 120 years.

This is certainly four times longer than a nuclear power station.

But to mitigate its efects on the environment, they say it should:

• be publicly led as a project and publicly owned as an asset to avoid short-termist decisions and ensure the long-term public interest

• be fully compliant with European Directives on habitats and birds and with a long-term commitment to creating compensatory habitats on an unprecedented scale

• investigate a habitat creation that addresses the impacts of climate change over the long term.

The best tidal stream sites are in the north of Scotland, with significant potential also around north Wales (Anglesey where it could replace the power lost by the closure of Wylfa nuclear power station with marine current turbines), Northern Ireland, and the Channel Islands.

The tidal range resource is concentrated in the estuaries off the west coast of Britain, including the Severn, the Mersey and the Humber.

The UK is leading the world in the development of a wide range of tidal stream devices, several of which are at the testing stage. The UK must ‘stay the course’ in developing these technologies, as the export and climate change benefits are potentially very large.

Despite the encouraging progress made so far, Government could do more to assist these emerging technologies, particularly through flexible financial support, and by providing additional resources to the European Marine Energy Centre in Orkney.

On tidal lagoons, the SDC found that there is a lack of available evidence on the costs and environmental impacts, mainly due to the absence of any practical experience. We have called on Government to support the development of one or more demonstration project, which would help provide real-life data on their economic and environmental viability.

> Tidal Power report