Table 2. Summary of short-listed proposals Project construction Installed capacity Cost Shoots barrage 1.05 GW £3.2 bn Beachley barrage 625 MW £2.3 bn Fleming lagoon 1.36 GW £4.0 bn Bridgewater Bay lagoon 1.36 GW £3.8 bn Cardiff-Weston barrage 8.64 GW £20.9 bn