Hydro Electric Power Plant

HYDRO ELECTRIC POWER PLANT:

1 Components Of Hydro Electric Power Plant

2 Working Principle Of Hydro Electric Power Plant

3 Classification Of Hydro Electric Power Plant

1 COMPONENTS OF HYDRO ELECTRIC POWER PLANT:

Reservoir :

Water is collected during rainy season

•         It is stored in the reservoir.

•         A dam is built across the river adequate water head.

Penstock :

• It is a passage through which water flows from reservoir to turbine.

Surge Tank :

•           It is installed along the penstock (between turbine and reservoir)

•         To control or regulate the sudden water over flow and to protect the penstock from bursting.

•         It reduces the pressure and avoids damage to the penstock due to the water hammer effect.

•         When the load on the turbine is decreased there will be a back flow, which causes increase or decrease in pressure. It is known as water hammer.

•         Power House :

•           It is building that houses that water turbine, generator, transformer and control room.

•         Water Turbine:

•         Water turbines such as Pelton, Kaplan and Francis are used to convert pressure and kinetic energy of flowing water into mechanical energy.

•         Draft Tube:

•           It is connected to the outlet of the turbine.

•         Tailrace:

•           It refers to the downstream level of water discharged from turbine.

•         Generator :

•         It is a machine used to convert mechanical energy into electrical energy.

•         Step up transformer:

•         It converts the Alternating Current (AC) into high voltage current suitable for transmission.

2 WORKING PRINCIPLE OF HYDRO ELECTRIC POWER PLANT:

•         It uses the potential energy of water of water stored in a reservoir.

•         The water from the reservoir through a penstock and then forced through nozzle or nozzles before reaching the turbine.

•         The hydraulic turbine converts the kinetic energy of water under pressure into mechanical energy.

•                     The shaft of the turbine is coupled to a generator that generates electricity

•                     The electricity generated is fed to the step-up transformer to increase its voltage.

•                     Power is fed to the transmission lines for distribution.

•                     The output power of Hydel power plant depends on the head of water stored in the reservoir and the quantity of water discharged

3 CLASSIFICATION OF HYDRO ELECTRIC POWER PLANT:

Factors to be considered for the location of hydro electric Power

Availability of Water:

Adequate water must be available with good head.

Cost and type of Land:

Bearing capacity of the land should be good to withstand huge structures and equipments.

Storage of Water :

A dam must be constructed to store the large quantity of water in order to cope with variations of water availability through out the year.

Transportation Facilities :

The site should be accessible by rail and road for easy transportation of equipments and machinery.

Pumped storage facilities :

The pumping facilities to reuse the water should be possible.

Merits of Hydro Electric Power Plant:

•         Requires no fuels and hence pollution free.

•           Low operating cost.

•           Simple in construction and requires less maintenance.

•           Skilled personnel is required for construction.

•           High cost of transmission as plant is normally required far off from hilly areas.

•           Period of delay causes the delay in the commissioning of the plant.

•         Construction of new hydel plant may need rehabilitation of people and payment compensation for land acquisition.