Assessment of wave energy and tidal current energy resources at the sea north of Chudao Island

The National Marine Energy Test Site of China is located in the Yellow Sea, north of Chudao Island and about 2 km away from Shandong Province. It is mainly aimed at the deployment and testing of small-scale prototypes of wave energy and tidal current energy converters. In this study, wave energy and tidal current energy resources around the test field were evaluated using ocean models. A spectral wind-wave model and a two-dimensional hydrodynamic model were used to simulate the wave energy and tidal current energy, respectively. The simulation results were validated using the observations, and showed good agreement with the observed wave, surface elevation and tidal current. Further, wave characteristic and wave energy resources were analyzed and the results showed that the spatial distribution of wave field was nearly coincident with an isobath, and gradually decreased from the outer sea to the coastal zones. The 10-year averaged significant wave height in the sea was about 0.6-0.8 m, and wave energy density was 2.0-2.8 kW/m. For the latter, we observed a significant difference with the seasons, the energy density being stronger in winter up to 6.5 kW/m, and weaker in summer with no more than 1.0 kW/m. Evaluation of tidal current energy resources showed a micro-tidal zone, and relatively weak tidal current energy. Tidal current energy density of the test field closed to the island was relatively stronger than that observed in the north, with the maximum tidal energy density of about 125-200 W/m
²
, which could only be used to test small-scale tidal energy converters.