THERMAL POWER STATIONS
Thermal energy is the major source of power generation in India. More than 60% of electric power is produced by steam plants in India. India has large deposit of coal (about 170 billion tonnes), 5th largest in world. Indian coals are classified as A-G grade coals.
In Steam power plants, the heat of combustion of fossil fuels is utilized by the boilers to raise steam at high pressure and temperature. The steam so produced is used in driving the steam turbines or sometimes steam engines couples to generators and thus in generating electrical energy.
Steam turbines or steam engines used in steam power plants not only act as prime movers but also as drives for auxiliary equipment, such as pumps, stokers fans etc.
Steam power plants may be installed either to generate electrical energy only or generate electrical energy along with generation of steam for industrial purposes such as in paper mills, textile mills, sugar mills and refineries, chemical works, plastic manufacture, food manufacture etc.
The steam for process purposes is extracted from a certain section of turbine and the remaining steam is allowed to expand in the turbine. Alternatively the exhaust steam may be used for process purposes.
Thermal stations can be private industrial plants and central station.
Advantages And Disadvantages Of A Thermal Power Plant
Advantages of Thermal Power Plant
▪ Less initial cost as compared to other generating stations.
▪ It requires less land as compared to hydro power plant.
▪ The fuel (i.e. coal) is cheaper.
▪ The cost of generation is lesser than that of diesel power plants.
Disadvantages of Thermal Power Plant
▪ It pollutes the atmosphere due to the production of large amount of smoke. This is one of the causes of global warming.
▪ The overall efficiency of a thermal power station is low (less than 30%).
▪ Requires long time for errection and put into action.
▪ Costlier in operating in comparison with that of Hydro and Nuclear power plants.
▪ Requirement of water in huge quantity.
|Thermal power plant