The basic principle of a hydroelectric power plant lies in the spinning of a turbine using the force of water in tandem with gravity. The water held back by a dam or in a pumped storage lake has potential energy. As water passes through the penstock it builds kinetic energy which is then used to spin the turbines.
Tidal power plants also work based on gravity, however it is the action of the moon's gravity that powers them. As tides go out and pull water from estuaries, they create a current which spins the turbine. As the tide rises, a current forms in the opposite direction and again propels the blades of the turbine.
Tidal power plants also work based on gravity, however it is the action of the moon's gravity that powers them. As tides go out and pull water from estuaries, they create a current which spins the turbine. As the tide rises, a current forms in the opposite direction and again propels the blades of the turbine.