Explain Generating Stations or Power Plants
A power plant or generating station is an industrial location where electrical power is generated in a large scale. A power plant consists of prime mover coupled with alternator for production of electricity. Prime mover (or Turbine) converts energy from some other form (e.g. water, steam etc) into mechanical energy and electric generators convert mechanical energy into electrical. Electric generators used in power plants to produce AC electric power are popularly called as alternators. There are various types of energy sources which are used to generate electrical power. Most of the power stations use fossil fuels such as coal, oil or natural gas to generate electricity. There are others sources too, such as nuclear power, hydro power, renewable energy sources etc.
The Various types of Generating Stations are
- Hydroelectric Generating station
- Steam / Thermal Generating Station.
- Nuclear Generating Station.
- Diesel Generating Station.
Hydro Electric Generating Station
Hydroelectric power generation involves the storage of a water, conversion of the potential energy of the water into mechanical (kinetic) energy through turbine, and conversion of the mechanical energy to electrical energy through electric generator.
Hydro-electric Generating stations are generally located in hilly areas where dams can be built conveniently and large water reservoirs can be obtained. In a hydro-electric generating station, water head is created by constructing a dam across a river or lake. Water stored in a dam possesses potential energy. From the dam, water is led to fall on turbine blades, turbine starts to rotate.in this way water turbine converts the potential energy of water into mechanical energy. The turbine in turn drives the alternator (generator) which converts mechanical energy into electrical energy.
Steam / Thermal Generating Station (or thermal power plant)
Steam Power plant is generating station which generates electrical energy by burning of fossil fuels mainly coal. It is sometimes called thermal power plant. The steam power station works on the Rankine cycle In Steam generating station a fossil fuel such as coal is burned to produce heat. This heat is then used to boil the water and convert it into the super-heated steam. The super-heated steam is passed into a steam turbine. The Steam turbine are rotated due to the pressure of the steam. The Steam is mechanically coupled with the rotor of the alternator/ generator. with the rotation of steam turbine, the rotor of the alternator also rotates, Electrical energy is produced.
Nuclear Power Plant
in these power plants nuclear energy is converted into electrical energy. Nuclear energy is obtained by nuclear fission of heavy elements such as Uranium or Thorium in a special reactor called nuclear reactor. in these power plants the heat generated by the reactor, converts water into steam, which spins a turbine, which in turn rotates the generator, thus electrical energy is produced.
Diesel Power Plant
A generating station in which diesel engine is used as the prime mover for the generation of electrical energy is known as diesel power station. For generating electrical power, it is essential to rotate the rotor of an alternator by means of a prime mover. The prime mover can be driven by different methods. Using diesel engine as prime mover is one of the popular methods of generating power. When prime mover of the alternators is diesel engine, the power station is called diesel power station. The mechanical power required for driving alternator comes from combustion of diesel. As the diesel costs high, this type of power station is not suitable for producing power in large scale in our country. But for small scale production of electric power, and where, there is no other easily available alternatives of producing electric power, diesel power station is used.