How Hydropower Power Plant Works

Hydropower power plant generates at least 20% of the world electricity supply. Also, according to the hydropower facts by the National Renewable Energy Laboratory, there are more than 2,000 of hydropower station operating in USA. It provides about 10% of the USA electricity, making water power as the biggest renewable energy resource in the country. But do you really know how the hydropower power plant able to generate electricity?

Well, the hydro power plant is utilizing the energy of the flowing water. A hydro power plant usually made up of several devices like turbine, generator, and transformer. These devices can capture the kinetic energy of water and convert it into electricity.

Continue reading this article to know the clear concept of how a hydropower station works and the description of each of its components function.

Hydropower power plant schematic

The schematic of hydropower station above show how the water flow can be used to produce electricity. For more information see the explanation of each component below:

Dam – most of conventional hydropower power plant use dam to block the water and keep them in the reservoir. If the dam built correctly, the reservoir should be able to used for recreational purpose like fishing or rafting.

Intake – the gates of the dam that only open to let the water flow through the penstock.

Penstock – the pipeline that leads the water flow to the turbine

Turbine – set of blades that shaped like a propeller. These large blades are connected to a generator by a shaft. Unless these blades are turning, the generator cannot produce the electricity.

Generator – when the turbine blades are rotating, so do the magnets inside the generator. This huge magnet rotates past a copper coil, causing a moving electron that generates the alternates current (AC).

Transformer – as the generator generates the AC, transformers convert it to a higher voltage current so the electricity current is strong enough to be transmitted through the power lines.

Power lines – a set of wires that are used to transmit the electricity. Usually consists of four wires; one is used as the grounding wire while the other three are used for the transmission.

Outflow – a pipeline that leads the used water flowing back to river.

The explanation of how hydropower power plant works

The reservoir stores the water. As the intakes opened, the water is flowing through the penstock. When the water flows through the penstock, it builds up a pressure that strikes the turbine and its kinetic energy turns the blades of the turbine. This process is causing the generator to turns as well, so it can produce the electricity. Transformers strengthen electricity and then they are transmitted through the power lines. The amount of generated electricity depends on the volume of the water flow and the height difference between the reservoir surface and the turbines.

What happen to the water that used to turns the turbine? They had finished their task, so now it is time to return them to where they belong: the river. The water is directed back to the river stream through the outflow, until the natural evaporation process brings them back to replenish the reservoir through the rain. This starts the cycle of hydropower power plant again to produce electricity.