On 5 May, 21:16, Roger wrote: [snip]
But May 5th was a New Moon, so the tidal variation was at its maximum for the month. For Barry, just a week later, the values are 9.2/3.4, a
48% drop in range. For Hunstanton, which is inside The Wash, the values are 5.9/1.8, partly due to The Wash itself, but mostly due to it being sheltered from the Atlantic swell by the rest of the UK. This is hugely lower than is available in the Severn.To generate all the UK's electricity from tides, you need 20 areas as big as the Severn estuary with the same tidal range, or at least 50 similar areas of average tide height. I lost the reference for it, but ISTR that tidal barrages become less efficient as the tidal range decreases.
OK, so 50 x 185 =3D 9250, not 18000, but it's still an enormous area, requiring infeasible amounts of civil engineering compared with e.g.
30 nuclear power stations.TL