A feasibility study of 10 project options lasted about a year before the proposed five shortlisted alternatives were chosen:

• Cardiff Weston Barrage (8.6GW, costing £19.6B-£22.2B (US$27.6B-US$31.2B));

• Bridgwater bay Lagoon (1.36GW, generating 2.6TWh/year and costing £3.4B-£4.1B (US$4.8B-US$5.75B));

• Fleming Lagoon (1.36GW, generating 2.3TWh/year and costing £4.1B-£4.9B (US$5.75B-US$6.9B));

• Shoots Barrage (1.05GW, generating 2.7TWh/year); and,

• Beachley Barrage (625MW, generating 1.6TWh/year and costing £2.1B-£2.5B (US$3B-US$3.5B)).

The Department of Energy and Climate Change (DECC) has launched a three-month public consultation on all 10 projects and its proposed shortlist. The consultation ends 23 April. Following analysis, a final shortlist will be issued to go forward to the next stage of study, which will be followed by a further public consultation.

DECC said a final decision on the tidal power exploitation at the Severn is to be made next year.

The DECC also announced £0.5M (US$0.7M) to fund development work on technologies such as tidal reefs and fences.