Thermal Power Plant part-1

Thermal power plant 

Thermal power plant converts the chemical energy of the fossil fuel into electrical energy
Thermal:- Thermal is a movement of rising warm air.
It is taken from Greek word 'Therme'  which means heat.
In thermal power plant we derive heat by burning coal so we refer it as a thermal power plant.

Why thermal power plant is also called as steam power plant ?
Because in this power plant we use steam of water of high pressure to drive the steam turbine which rotates the alternator.
Alternator is also known as synchronous generator which is used in thermal power plant due to its synchronous speed that is constant speed at varying input.

Sometimes thermal power plant is also referred as coal power plant, why ?
Because in this Thermal power plant we use coal as a fuel to convert water into steam and hence we refer it as coal power plant also.

Site selection of a thermal power plant

1. Availability of raw material 
2.  Nature of land 
3.  Cost of land 
4.  Availability of water 
5.  Transport facilities 
6.  Ash disposal facilities.
7. Coal handling facilities.
8.  Availability of labour and workers.
9.  Size of plant.
10.  Load centres near the power plant. 
11.  Future extension of Plant.
12.  Public problems and issues.
13.  Environmental effects etc.

 General layout of thermal power plant 

To understand working and General Layout Please open this link  https://youtu.be/Gab4wb1ZwyY

Working of thermal power plant

1. First the pulverized coal is burnt into the Furnace of steam boiler.
2. High pressure steam is produced in the boiler.
3. This  steam is then passes through the superheater where it further heated up using flue gases ( which is produced by the burning of coal it contains carbon monoxide and warm air etc.).
4. In steam turbine this steam force rotate the turbine blades that means here in the turbine high pressure steam is converted into mechanical energy.
5. After rotating turbine blades steam has lost its high pressure, passes out of turbine and enters into a condenser.
6. In condenser the cold water is circulated with the help of cooling tower through pump which condenses the low pressure steam.
7. Cooling tower takes water from Lake river sea or canal.
8. This condense water is then further supply to the Economiser where feeding water is applied through the feed water pump to balance the requirement of water which losses due to the different operations.
9. To burn the coal, air is necessary which is taken from the atmosphere through draught fan.
10. This atmospheric air is passes through the air preheater (in which flue gases passed from the Economiser) preheated the air and then passes through to the Furnace.
11. The flue gases (less warm) is then passes through the chimney into the atmosphere which is hazardous for our environment. It is the one of the main disadvantage or limitation of thermal power plant.
12. The steam turbine in the thermal power plant act as a prime mover of alternator which produces electricity.

Advantages of thermal power plant

1. Less initial cost. 
2. Require less land.
3. coal is cheaper.
4.  cost of generation is cheap.
5. They can respond to rapidly changing loads without difficulty.
6. They can be located very near the load center.
7. As this plant can be set up near the industry transmission cost are reduced etc.

Disadvantages of thermal power plant

1. Maintenance cost is high.
2. Operating cost is high.
3. Coal and ash handling is difficult.
4. Plant efficiency is Low.
5. Pollutes the atmosphere.
6. Required large amount of water and coal etc.