Hydroelectric power device

A hydroelectric power device, comprising:

• a float being hollow or constructed of a buoyant material;
• a casing member having a water path formed by a channel that passes through the casing member from a water inlet opening on a water entry side of the casing member to a water outlet opening on a water discharge side of the casing member, and wherein the casing member is provided at a bottom side of the float and submerged in water;
• rotating shafts located substantially vertically within the casing member and passing through the channel, wherein a top end of each rotating shaft protrudes through the upper surface of the casing member and above the surface of the water through the float;
• a rotor with a plurality of rotor blades or vanes positioned within the channel and affixed to each rotating shaft;
• a power generator in mechanical communication with each rotating shaft;
• and
• a tapered portion located at the water inlet opening on the water entry side of the casing member and having a gradually decreasing width in a water width direction and depth in a water depth direction towards the downstream side, wherein the tapered portion is configured to accelerate water flow at a center of the channel to operate the blades or vanes located between the rotating shafts, thereby rotating the rotary shafts in opposite directions.