Numerical simulation of tidal current energy in Yangtze Estuary-Hangzhou Bay, China

Abstract

Tidal current power generation system extracts energy by transferring the kinetic energy of tidal movement to the motion of power turbines. The long coastline of China contains abundant tidal energy, but not all coastal area worth exploiting. It is generally considered that a mean spring peak tidal current of at least 2 m/s is required for tidal current power exploitation. Thus we choose to evaluate the tidal kinetic energy of East China Sea coastal area where 95 waterways contained, accounting for 78.6% of China's tidal kinetic energy. Considering the interaction between the Yangtze Estuary and Hangzhou Bay, a high resolution model with unstructured 3D grid system FVCOM (finite volume coastal ocean model) has been applied to simulate tidal motion in the Yangtze Estuary-Hangzhou Bay. The numerical results of the refined model has been validated with: (a) measured tidal currents data after harmonic analysis; (b) measured tide level hydrograph and velocity which were observed by China's coastal physical oceanography and marine meteorological special investigation on the East China Sea during August, 2014. It is also noticed that the area where power density larger than 10 kW/m2 are mainly distributed over North Port of Yangtze Estuary and north of Hangzhou Bay, and the maximal value of the possible maximum velocity of the tidal current reaches 3.0–3.5 m/s at Hangzhou Bay.