THE SEVERN BARRAGE PROJECT

The Severn Barrage Project

The Severn Barrage Project

Introduction

The tidal range in the Severn Estuary is one of the highest in the world, reaching over 13 metres, so ideas for taking advantage of the Severn's high tidal range for energy generation have long been talked about by the public and energy specialists alike. Numerous studies focussed around an electricity generating barrage were carried out between 1974 and 1988 following which a scheme was drawn up. It was called the Severn Barrage project and is essentially the design which has been proposed since. Yet the scheme was then and has since been widely considered as economically unattractive and also gave rise to environmental concerns.

The Government's recent energy review sparked renewed public debate about the construction of this Severn barrage scheme following further publicity by barrage supporters. This was perhaps unsurprising as the urgent need to address global climate change by reducing fossil fuel use is becoming widely understood. Barrage supporters have cited new reasons for a re-examination of the barrage: rising world energy prices, 'low carbon' energy security, global warming related flood defence and coastal protection benefits, the potential for new habitat creation and the inevitable habitat changes due to sea-level rise, improved waterfront amenity, and a road and possible rail link between south Wales and the west of England. Perhaps more surprisingly, the Welsh Assembly Government in its 'memorandum' response to the energy review said that it supported a new feasibility study into the barrage scheme.

In July the Government announced its review findings in a document called 'The Energy Challenge'. It stated that the government will work with 'key interested parties to explore the issues arising on the tidal resource in the UK, including the Severn Estuary, including potential costs and benefits of developments using the range of tidal technologies and their public acceptability'.

History and Background

On 22nd January 2008, the Secretary of State for Business, Enterprise and Regulatory Reform (BERR) published the terms of reference for a feasibility study into the use of tidal power to generate electricity in the Severn estuary. This followed an earlier report by the Sustainable Development Commission (SDC) about tidal power in the UK. The SDC report had a specific focus on potential projects on the Severn, and in particular on the possibility of a Severn barrage.

These developments are bringing into focus a longstanding debate over the potential for the Severn estuary to be used as a source of electricity generation. In theory, the estuary contains natural conditions that could allow the generation of significant amounts of electricity (potentially up to about 4.5% of UK demand). Realising this, or smaller, levels of generation comes with some costs (e.g. in terms of construction, of the site specific environmental impacts) and some benefits (e.g. in terms of electricity generation that emits relatively little greenhouse gas). The extent to which the benefits outweigh the costs is subject to ongoing analysis.

The case for supporting renewables

There is a good case for providing additional support for renewables ...