# Thermal Power Plant Efficiency | Thermal Efficiency And Overall Efficiency Of Thermal Power Plant

## WHAT IS THERMAL EFFICIENCY OF THERMAL POWER PLANT?

Thermal Efficiency of Thermal Power Plant is the ratio of equivalent heat energy which is converted to mechanical energy flow to the turbine shaft to the heat energy of coal combustion.

The thermal efficiency of thermal power plant is nearly 30%. It means, if 1000 calories of heat energy is produced by coal combustion then only 300 calories will be flow to the turbine shaft. Maximum energy is lost by condenser and rest of energies are lost in flue gases, ash etc.

## WHAT IS OVERALL EFFICIENCY OF THERMAL POWER PLANT?

Overall Efficiency of Thermal power plant is the ratio of equivalent heat energy which is ultimately converted to electrical energy coming from turbine shaft to the heat energy of coal combustion.

The overall efficiency of thermal power plant is determined by the multiplication of the thermal efficiency of the power plant and the efficiency of generation or electrical efficiency.

The overall efficiency of a thermal power plant is nearly 29% and it is less than the thermal efficiency because some energy is lost by alternator. Now some heat sharing device is used in modern super-critical-pressure steam power plant to increase the overall efficiency and the efficiency is reached nearly 50% using this device.

## THERMAL POWER PLANT EFFICIENCY

Efficiency of thermal power plant is quite low. It mainly depends upon following three major factors:

### 3. Pressure in the condenser

A huge amount of heat is lost in the condenser due to various stages of the plant. Heat energy cannot be converted into mechanical energy without temperature difference and according to the thermodynamics law we know, greater the temperature difference, greater the heat energy is converted into mechanical energy. So, thermal efficiency increases with the increase in temperature and the pressure of steam are entering the turbine. The thermal efficiency is also effectively increased by decreasing the pressure in the condenser but if the pressure of the condenser is too low (nearly 0.04kg/cm2), the plant will run at low efficiency according to the thermodynamics law .