The largest scheme being proposed would generate up to 7% of the UK's energy
The Department for Energy and Climate change has unveiled its shortlist of schemes to generate power from the tides in the Severn Estuary.
The largest scheme on the shortlist is the 8.6GW Cardiff-Weston Barrage which would generate 5-7% of the UK鈥檚 energy needs.
Two other barrages have also been selected: the Shoots Barrage, which would generate 1.05GW of power, and the Beachley Barrage, which has a generating capacity of 625MW.
The other shortlisted schemes are lagoon projects, which harness the tide of a section of the Estuary.
Bridgwater Bay Lagoon in England and Fleming Lagoon in Wales generate would each generate 1.36GW of power.
Minister for Energy, Ed Miliband, said: "The Severn Estuary has massive potential to help achieve our climate change and renewable energy targets. We want to see how that potential compares against the other options for meeting our goals.鈥