A power generation apparatus utilizing water current energy comprising:
- an installation base installed in the sea or a freshwater body,
- a rotary body mounted to said installation base and configured to rotate relative to the installation base, and
- a power generator generating power by rotation of said rotary body with respect to said installation base, and the power generator is provided inside of the rotary body, wherein
- a rotary shaft axis of said rotary body is set in a vertical direction being substantially perpendicular to a flow plane of water current in the sea or in the freshwater body where the rotary body is set,
- said rotary body has a plurality of mounting frames attached from the rotary body radially, said mounting frames having first ends of flat-plate-shaped pressure receiving plates attached to the mounting frames to be able to pivot at top side positions offset from said rotary shaft axis, and a specific gravity of said pressure receiving plates is set smaller than the specific gravity of the seawater or freshwater where the apparatus is set so as to enable generation of buoyancy in said pressure receiving plates in the sea or in the freshwater body,
- stoppers are provided for limiting ranges of angle of pivot of said pressure receiving plates,
- output power of said power generator is transmitted by cable to land close to said installation base or a ship on the sea or freshwater body,
- force generated at said pressure receiving plates due to tidal current or water current in the sea or freshwater body, the buoyancy of said pressure receiving plates, and said stoppers enable the rotary body to be reliably made to rotate and generate power,
- an angular range over which said pressure receiving plates pivot is 4° to 90° in a range downward from a locus plane when ends of the mounting sides of said pressure receiving plates rotate about said rotary shaft axis,
- a specific gravity of said pressure receiving plates, obtained by dividing the mass of said pressure receiving plates by the mass of a volume of pure water at 4° C., is made 0.95 to 0.99 of the specific gravity of the seawater or freshwater in which the rotary body is set, and
- said rotary body is structured as a circular cross-section vertical cylinder which is provided at said installation base so as to rotate relative to the installation base.