The term water mills has commonly designated run-of-the-river mills situated on waterways where there was/is no tidal current. The terms sea mill, and later tide mill, designated mills that took advantage of the tides with or without retaining ponds. There were thus tide mills that took advantage of the ebb and/or flood current. Some such […]

The tidal current was used by water mills on Evrepos Strait, in Cephalonia, in the floating tide mills on the Danube, Tiber, Seine and Russian rivers. A plant func­tioned briefly in northwestern Iceland and another has been mentioned for the Faroe Islands. The Danube tide mills used undershot wheels since Roman times to harness the […]

Twenty years ago, it was felt that a scheme most suitable to attain an acceptable, favorable benefit to cost ratio (“rentability”) would be one in which rotors would be anchored, but suspended in mid-water—precisely to avoid wave influence—and let drive hydraulic pumps, while conversion to electricity would occur at a central facility servicing several rotors; […]

Major tidal currents are encountered in the Arctic Ocean, the English Channel, Irish Sea, Skagerrak-Kattegat, Hebrides, the gulfs of Mexico and of St Lawrence, the Bay of Fundy, such rivers as the Amazon and Rio de la Plata, the straits of Magellan, Gibraltar, Messina, Sicily, Bosporus. The tidal range is observed as far as 800 […]

To calculate Pf(region) or linear potential for a specific region, requires to know the elevation above sea-level of the individual basins (Hi) and the mean run-off of sev­eral basins; an estimate of the theoretical linear value of the per annum potential, in millions of kWh (kWh.106), is now possible (Pf). Taking Hmed as the median […]

Flow-of-the-river potential is directly proportional to elevation above sea level and precipitation run-off. If a “sector” is the distance between two successive confinements—about 10 km—the linear potential of a river is given in the eq. (8.2) Pf = 9.8xQmXH (8.2) wherein H is the elevation difference, expressed in meters, above sea-level, between points of origin […]

The tide phenomenon is the periodic motion of the waters of the sea—and is ob­served upstream of several rivers—caused by celestial bodies, mainly the moon and the sun. The tide results from the gravitational pull and the earth’s rotation. Tide and tidal currents must be differentiated, for the relation between them is not simple, nor […]

8.1 Introduction With at least sixty major papers in print and several international conferences on the subject, over the last decade, it appears that, contrary to assertions made in some trade-and-news journals, interest in tidal power—using barrages—is far from being on the wane.1,2 This is particularly true in the Far East, viz. China, Japan, Korea.3 […]