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

The diagram illustrates a hydroelectric power plant and its process of generating electricity.

Overall

, the process can be divided into two major steps: riverside and the power station which both can function differently

according to

the time of the day.

Firstly

, there is a dam constructed to accumulate

water

which has a narrow passage beneath

that is

only open during the day for

water

intake.

This

natural flow of liquid generates electricity in the daytime. Afterwards, it finds its way to the generator which consists of reversible turbines that operate before night-time and are connected to power lines and the national grid. At

last

, the

water

would be discharged into the low-level reservoir.

However

,

this

process is reversible during the night-time which begins with the flow of

water

from the lower level part of the river into the turbines which pump it upwards, initiating it to pass along the previously-mentioned narrow line beneath the dam, into the high-level reservoir.