THE CHARACTERISTICS OF TIDAL CURRENT AND TIDAL POWER GENERATION ENERGY AROUND GOTO ISLANDS

Abstract

 Tidal current energy is one of the promising ocean renewable energies to help Japan from energy shortage. The straits around Goto Islands in Nagasaki Prefecture are well known as the high tidal current velocity area and therefore are good candidate for the demonstration field and the prospective commercial tidal farm.
 The field surveys of the tidal current, the bathymetry, etc. were conducted at the Experimentation Fields set by Nagasaki Prefecture in Naru Strait and Tanoura Strait. Numerical simulation was also conducted for modeling the tidal current and the tidal energy features during a year, and the results were validated with the measured data. High tidal currents exist in both straits with the peak current velocity exceeding 2.7 m/s at the spring tide to generate 1MW by a planned tidal turbine. High current energy density areas suitable for the installation of turbines were confirmed in overall consideration of the tidal current energy and the sea bottom conditions.