Hydroelectric (hydel) power plants convert the energy stored in a water into electrical energy by the use of water turbines coupled with generators. The water from a height (water head) is allowed to fall on the blades of a turbine through long pipes or tunnels called penstocks. This causes the turbine blades...

Alternating Current (AC) — An electric current that reverses its direction many times a second at regular intervals.                                                        ...

The process of generating electricity follows a sequence that takes charge from the ground and works on it to produce energy. This energy is expressed in terms of voltage. The energy is transported through a system of distribution making use of energy and dumping the charge that has been spent back to the earth...