I grew up on the banks of the Bristol Channel in England, and nominated the secluded Ladye Bay for Michael's slideshow of TreeHuggers' favorite nature spots. So I've always had mixed feelings about the proposed massive Severn Barrage, a project so huge that some claimed it would singlehandedly provide 5% of the UK's electricity needs with predictable, reliable renewable energy.
I'm not the only one with reservations.A report from the Royal Society for Protection of Birds previously argued that the barrage was too expensive to make economic sense, even before environmental impacts were considered. Other groups have touted underwater tidal fences as a lower impact alternative.
Now Business Green reports on a new paper from Regen SW and Marine Energy Matters which claims the Severn Estuary would have more generating capacity if the barrage were not built at all, but resources were instead invested into more distributed alternatives:
The report outlines how tidal range installations in the inner estuary that use a small barrage and tidal lagoons could contribute up to 5GW of capacity, while a further 1.25GW could come from shallow tidal stream devices, such as turbines arranged on the sea bed.
The Bristol Channel also already has the 1.5GW Atlantic Array offshore wind project in development and the report says new turbine technology could double capacity by opening up deeper waters for exploitation. Meanwhile, wave energy devices in the outer reaches of the estuary could then deliver more than 5GW of additional capacity.
Interestingly, the paper also argues that distributed projects would provide a provide a better return on the capital invested and produce more jobs.
What's not to like about that?