A numerical study of tidal farm efficiency in the Western Passage, US and Canada

Turbines are implemented in the regional ocean circulation model to determine the energy extraction efficiency of tidal farms. A power curve is determined for different values of flow blockage when 10 turbines are distributed evenly across the Western Passage in the middle 1/3 of the water column. A speed reduction coefficient of 0.6 represents the most efficient case with ~ 3.95% of the undisturbed in-stream energy being taken. Efficiency is also estimated for different densities and distributions of turbines. The optimum density for a single row appears to be one turbine in every three cells. When turbines are allocated on parallel rows in the direct shadow of one to another the efficiency is reduced because of the wakes, whereas in the lattice form the efficiency is benefited from the speed gain in turbine gaps produced by the neighboring rows.