double basin?

Question

does someone know what it si ?
I only know it is used to generate power by pumping up water ,but someone said this tidal plant can release a 'constant 'flow to generate power
can someone explain how it works ?

Answer 1

Double basins provide a way to maintain continuous tidal energy output that a single-basin design cannot. With a single basin, the basin and ocean levels must be equal at least twice during each tidal cycle, and during periods of near-equality (low head) no appreciable power can be generated.
From the reference, "With two basins, one is filled at high tide and the other is emptied at low tide. Turbines are placed between the basins. Two-basin schemes offer advantages over normal schemes in that generation time can be adjusted with high flexibility and it is also possible to generate almost continuously. In normal estuarine situations, however, two-basin schemes are very expensive to construct due to the cost of the extra length of barrage. There are some favourable geographies, however, which are well suited to this type of scheme." ("Barrage" is the barrier or dam that impounds the water.)
I would imagine additional power could be generated during the filling of the high basin and the emptying of the low basin, although the head may not be enough to make installation of the added generating equipment practical.