Theory of Thermal Power Station
The theory of thermal power station or working of thermal power station is very simple. A power
generation plant mainly consists of alternatorruns with help of steam turbine. The steam is obtained
from high pressure boilers. Generally in India, bituminous coal, brown coal and peat are used as fuel
of boiler. The bituminous coal is used as boiler fuel has volatile matter from 8 to 33 % and ash
content 5 to 16 %. To increase the thermal efficiency, the coal is used in the boiler in powder form.
In coal thermal power plant, the steam is produced in high pressure in the steamboiler due to
burning of fuel (pulverized coal) in boiler furnaces. This steam is further supper heated in a super
heater. This supper heated steam then enters into the turbine and rotates the turbine blades. The
turbine is mechanically so coupled with alternator that its rotor will rotate with the rotation of turbine
blades. After entering in turbine the steam pressure suddenly falls and corresponding volume of the
steam increases. After imparting energy to the turbine rotor the steam passes out of the turbine
blades into the condenser. In the condenser the cold water is circulated with the help of pump which
condenses the low pressure wet steam. This condensed water is further supplied to low pressure
water heater where the low pressure steam increases the temperature of this feed water, it is again
heated in high pressure.
For better understanding we furnish every step of function of a thermal power station as follows,
1) First the pulverized coal is burnt into the furnaceofsteamboiler.
2) High pressure steam is produced in the boiler.
3) This steam is then passed through the super heater, where it further heated up.
4) This supper heated steam is then entered into a turbine at high speed.
5)In turbine this steam force rotates the turbine blades that means here in the turbine the stored
potential energy of the high pressured steam is converted into mechanical energy.