Components of Hydro Electric Power Plant

Hydro electric power plant:

• Plant from which hydroelectricity is produced
• Hydroelectricity is the term referring to electricity generated by hydropower
• The production of electrical power through the use of the gravitational force of falling or flowing water. 
• It is the most widely used form of renewable energy.

Components of hydroelectric power plant:

Mainly, there are six components in the hydroelectric power plant.

1.Dam
2.Water Reservoir
3.Intake or control valve
4.Pen stroke
5.Water turbine
6.Generator

Dam

• The dam is most important components of HEPP.
• It should be built at a location where the height of the river is sufficient to get the maximum possible potential energy from water.
• This is civil component.

Water Reservoir

• The water reservoir is the place behind the dam where water is stored. 
• The water in the reservoir is located higher than the rest of the dam structure. 
• The height of water in the reservoir decides how much potential energy the water possesses. 
• The higher the height of water, the more its potential energy. 

Intake or control gates

• These are the gates built on the inside of the dam. The water from reservoir is released and controlled through these gates.
• These are called inlet gates because water enters the power generation unit through these gates. 
• When the control gates are opened the water flows due to gravity through the penstock and towards the turbines. 
• The water flowing through the gates possesses potential as well as kinetic energy.

The Penstock

• The penstock is the long pipe or the shaft that carries the water flowing from the reservoir towards the power generation unit, comprised of the turbines and generator. 
• The water in the penstock possesses kinetic energy due to its motion and potential energy due to its height.
• The total amount of power generated in the hydroelectric power plant depends on the height of the water reservoir and the amount of water flowing through the penstock. 
• The amount of water flowing through the penstock is controlled by the control gates.

Water turbine

• Water flowing from the penstock is allowed to enter the power generation unit, which houses the turbine and the generator.
• When water falls on the blades of the turbine(in rotor) the kinetic and potential energy of water is converted into the rotational motion of the blades of the turbine. The rotating blades causes the shaft of the turbine to also rotate.

 The turbine shaft is enclosed inside the generator. 

• In most hydroelectric power plants there is more than one power generation unit.
• There is large difference in height between the level of turbine and level of water in the reservoir. This difference in height, also known as the head of water, decides the total amount of power that can be generated in the hydroelectric power plant. 
• There are various types of water turbines such as Kaplan turbine, Francis turbine, Pelton wheels etc. The type of turbine used in the hydroelectric power plant depends on the height of the reservoir, quantity of water and the total power generation capacity

Generators

• It is in the generator where the electricity is produced. 
• The shaft of the water turbine rotates in the generator, which produces alternating current in the coils of the generator. 
• It is the rotation of the shaft inside the generator that produces magnetic field which is converted into electricity by electromagnetic field induction. Hence the rotation of the shaft of the turbine is crucial for the production of electricity and this is achieved by the kinetic and potential energy of water. Thus in hydroelectricity power plants potential energy of water is converted into electricity