The diagram below shows how electricity is generated in a hydroelectric power station. Summarize the information by selecting and reporting the main features, and make comparisons where relevant.

The diagram illustrates different steps of how the production of electricity is carried out in a hydroelectric power station.

It is clear that

there are several main stages in

this

process, beginning with water being taken from the river and ending with electricity being transferred to the national grid. As can be seen, in the first stage, water is brought from the river in the high-level reservoir via a dam's intake which is opened during the day and closed at night. In the daytime, it is controlled to flow directly to the reversible turbines located in the station in order to operate the generator .

Next,

electricity is generated and delivered through power lines to the national grid. Meanwhile, the left liquid

also

flows to the low-level reservoir.

Besides

, when it is nighttime, water from the lower area is transported back to those turbines so that it is pumped up to the initial high place in the river through the same route. The circulation

then

keeps running the same process.