How Is Hydroelectricity Produced Step by Step?

How Is Hydroelectricity Produced Step by Step

You know that hydroelectricity is a clean and safe form of energy, but you’re not sure how it all works. This article will explain exactly how is hydroelectricity produced step by step to understand this fascinating technology!

Hydropower is the primary source of renewable energy. The environmental benefits and the unlimited potential of the falling water make hydroelectricity a reliable power source. 

The basic energy generation principle is based on converting falling water’s kinetic energy to mechanical energy by the turbines coupled to the generators. The hydroelectric generators then convert the turbine’s mechanical energy to electric power in the hydroelectric power plant.

Key parts of hydroelectric power plant


Refers to the dam or reservoir that is used to store water temporarily. The size varies depending on the size of the power station. Reservoirs or barriers can be used for other purposes such as recreation and water supply. Spillways are channels that help discharge floodwater safely when dams are full. 

Intake structure

The purpose of the intake structure is to direct water into the penstocks, which are large pipes that direct water from the forebay to the turbines. Debris is prevented in the intake structure by constructing a rash rack. The flow of clean water is key to the continuous functionality of the turbines.

Surge chambers

The surge chambers execute pressure control close to the powerhouse. The cylindrical tanks minimize abrupt disruption of the power generation by controlling the acceleration of water through pressurized air.  


Turbines are devices with circular blades that convert the kinetic energy of the water into mechanical energy. The movement of the turbine is attributed to the high speed of the water from the reservoir that is channeled through the penstocks. The turbine’s shaft is connected to the generator that produces electric energy. 


A generator is a device that produces alternating currents by converting mechanical energy to electricity. The process is attributed to a rotating turbine that causes the spinning of magnets past copper coils, leading to the production of alternating current. Hydropower generator’s size varies depending on the size of the power plant


The powerhouse guarantees the protection of the mechanical, electric, electronic, and other components in the power station. The turbine and the generator are firmly fixed to the foundation of the powerhouse. Additionally, electronic and communication devices such as computers, the internet, and the supervisory control and data acquisition (SCADA) system are located in the powerhouse.  


Tailrace is the pipes used to direct the used water to the river. Tailrace is connected to the turbine by a draft tube connected to the exit point of the runner. The outflow is important in discharging the water and avoiding the destruction of the turbine, generator, and other components.

Hydroelectric power generation principle

1. Water cycle

The first stage in understanding the operations of the hydroelectric power station is the assessment of the water cycle. Sun radiation heats water bodies such as lakes, oceans, and rivers, leading to water evaporation. Subsequently, the condensation of the water vapor leads to the formation of clouds that precipitate in the form of snow and rain. 

The precipitation accumulates in water bodies leading to a continuous water cycle process. The collected water in the rivers is diverted and tapped in dams for power generation.  

2. Elevation difference and hydropower Generation 

Secondly, the height difference is key to hydropower energy generation. The dams are located on the raised side, while the powerhouse is on the lower area. The water storage system allows for the gravitational flow of water to the turbines on the lower side of the reservoir. The fall, also known as the head, allows water flow, leading to electricity generation. The elevation determines the amount of electricity generated.  

3. The turbine and generator in hydroelectric power

The penstocks allow the water to move faster from the reservoir to the turbine due to the elevation difference. The fast-flowing water from the reservoir via the penstock rotates the turbine plates converting kinetic energy to mechanical energy. Consequently, turbines spin the generator’s rotor, leading to the production of alternating current electricity from the turbine’s mechanical power. The conversion of water energy flowing from the forebay by the rotating turbine coupled to hydroelectric generator yields electric power.  

4. Faraday’s law and hydroelectric power generation 

The operation of the generator is based on the Faraday law of induction. According to the scientist, electricity flow is caused by the movement of magnets past an electric conductor. For that reason, the electromagnetic induction principle in the generator leads to the alteration of mechanical energy to electric energy. 

The revolution of the rotor at the fixed speed leads to the development of field poles past the copper conductor attached to the stator, leading to flow of energy and voltage development at the output terminals of the generator.

5. Factors determining power generated

The two main factors that influence the amount of electricity produced are the distance of the waterfall and the volume of the falling water. Large dams have large falls, leading to more energy generated. Similarly, the volume of water hitting the turbine is directly proportional to the electricity generated. Bigger rivers have large reservoirs leading to higher energy generation than smaller rivers. 

6. The step-up transformer and power transmission 

The voltage of the generated electricity is inadequate for transmission, necessitating suitable transformers to step up the voltage. Extra high voltage is economically desirable over long distances due to minimum power losses. The practice reduces the overheating associated with a high electric current in the transmission line. For example, a 400,000 volts transitions line is used to evacuate power to the substation and finally to the consumers. 

7. Power Station Control Room

An on-site or remote-control room is essential in maintaining hydroelectric power generation. The purpose of the facility is to enhance efficiency through effective decision-making. Key aspects in the control room include monitoring operations and initiation of commands to manage the situations at the facility. Internet technology and computerization are critical to effective power management. 

Additionally, futuristic technologies such as robotics and artificial intelligence allow for automation. Adopted control room technology depends on the size of the plant and financial resources.


A hydroelectric power plant is a renewable energy that converts water energy to electricity. Hydropower dams are used to store water used to turn turbines coupled to hydroelectric generators. 

However, critical concerns associated with hydroelectric power include displacement during reservoir construction and ecosystem alteration. Plants and other living organisms are affected in the generation process. The ecological problem is vital to the point of contention for conservations

Hydroelectric power is the most reliable form of renewable energy despite the environmental dilemmas. The zero carbon footprints and limited ecological degradation make water energy best in powering homes and industries. The source minimizes the pollution associated with carbon-based fuels promoting environmental sustainability.

Do you want to learn more about hydroelectric power? You may want to check out our ultimate guide on the advantages and disadvantages of hydroelectricity.

Recommended Reading:

Scroll to Top