Last year, the newly installed Conservative-Liberal Democrat government put the most ambitious of the shortlisted schemes, an 8.6GW barrage project, on ice, deeming it "high cost and high risk in comparison to other ways of generating low-carbon electricity" such as wind power, and arguing that it was "unlikely to attract the necessary private investment in current circumstances".
Power scheme that has spanned the decades
Visions of a span across the Severn Estuary have been occupying minds since at least Victorian times. In 1849, civil engineer Thomas Fulljames' drew up plans for a 1.6km-wide barrage as part of a large shipping harbour, while providing road and railway connections and flood protection - but no electricity.
6 January 2011 23:00 GMT
Updated
25 November 2012 15:18 GMT
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