Engineers try to tap tides in two ways: one involves building barrages across tidal estuaries that use tidal differences
in sea surface elevation, so that the flowing waters turn turbines in a similar fashion as hydropower installations.
The protection system can span widths of up to 60 metres, sustain large tidal differences
and be resistant to wind, currents and corrosion (seawater), according to the statement.
Capt Steve Gobbi, Peel Ports marine director, said: "The Mersey has one of the UK's largest tidal differences
The smallest tidal differences
, called "neap tides," come at the first and third quarters of the lunar month, when the forces exerted by lunar and solar gravity do more to cancel each other.
There are no planned or existing tidal power projects in the United States; in the United States only Alaska and Maine experience the large tidal differences
that are necessary to make such plants feasible.
of up to 30 feet and the intricately convoluted shoreline of the Korean peninsula's west coast contribute to the existence of extensive and very rich tidal flats.