The diagram below shows how electricity is generated in a hydroelectric power station.
The picture depicts the stages involved in the process of producing electricity in a hydroelectric power station. Overall, what stands out from the diagram is that the process begins with water flowing from the river into the reservoir and ends with electricity being transmitted from the power lines to the national grid. Another interesting point is that water is channeled in opposite directions during day and night time.
During the day, the water channeled from the river is stored in a high-level reservoir behind a dam. When the dam opens, the water flows downhill into a power station where it turns reversible turbines to generate electricity. The power created is transferred to a generator and then to the national grid via the power lines. The water runs from the power station into a low-level reservoir and is kept there until night time.
At night, when the demand is lower, the water in the low-level reservoir is pumped back into the high-level one via the same route; it stays there as the dam is closed to be ready for the morning process.