To distribute 8GW of power would need at least two new long-distance 400kV transmission lines. And because the 8GW would be generated when the tidal level difference across the barrage was at its maximum and would reduce to zero for several hours there would have to be equivalent standby plant available elsewhere on the system.
We also concluded that the unit cost of tidal power would be about three times that from either nuclear energy or coal.
The environmental impacts were also seen as unacceptable. Not only would there be major changes in the inter-tidal areas above the barrage, but there would be effects below which could damage the Ramsarsite in Bridgewater Bay.
It will be interesting to see if the new studies come to the same decisions.
MICHAEL GAMMON (F), former head of generation development, CEGB, firstname.lastname@example.org