London, UK [RenewableEnergyWorld.com] The UK government has published a list of 10 proposed projects for a tidal “barrage” across the Severn Estuary that will be the focus of a newly launched feasibility study. Commissioned by Secretary of State for Energy John Hutton, the study will see a short list published later this year highlighting which preferred proposals could be taken forward for more extensive research.
Commenting on the development Hutton said, “Harnessing the power of the Severn Estuary could be an engineering project of breathtaking scale and we will look at the full range of technologies and locations.”
The list of ten options is:
1. Outer Barrage from Minehead to Aberthaw: this would be the largest barrage and would make maximum use of the Severn Estuary tidal resource.
2. Middle Barrage from Brean Down to Lavernock Point: most well-studied option, known as the Cardiff-Weston barrage.
3. Middle Barrage from Hinkley to Lavernock Point: as option 2 but lands at Hinkley.
4. Inner Barrage (Shoots Barrage): also known as English Stones scheme and studied in detail by the Sustainable Development Commission.
5. Beachley Barrage: barrage further upstream, smaller generating capacity than Shoots.
6. Tidal Fence proposal: a barrier constructed over part of the Cardiff to Weston line, with open sections, incorporating tidal stream turbines to capture energy from the ebb and flood tides.
7. Lagoon enclosure on the Welsh grounds (Fleming lagoon): one of the previously studied Russell lagoons from 1980s.
8. Tidal lagoon concept: a proposal for a number of tidal lagoons.
9. Tidal reef proposal: a concept that would include floating turbines and caissons.
10. Severn Lake Scheme: a 1-km wide barrage in the same location as the Cardiff-Weston scheme designed to allow the construction of a number of additional features, including a wave farm on the seaward side and four marinas.
The tidal range on the Severn is the second largest in the world and has the potential to provide around 5% of the UK’s current electricity demand. The feasibility study will run for two years and will be a two-stage process with a decision point at the end of each. The first stage work, likely to run until late 2008, will focus on high level issues and short-listing potential tidal power project options.