Comparison of Gas Turbine and I.C. Engines

Sr. No.

Gas turbine

I.C. Engines

1.

The weight of gas turbine per kW power developed is low since the
working pressures are low required lighter construction.

The weight of I.C. engine per kW power developed is high since the
working pressures are high requiring heavy construction.

2.

Since there are no reciprocating parts, it is vibration free and
perfectly balanced.

Due to heavy reciprocating parts, these are subjected to vibrations
and balancing is not perfect.

3.

It required less floor area and lighter foundation.

It required large floor area and heavy foundation.

4.

The installation and running cost is low since it can use cheaper
fuels.

The insulation and running cost is high since it use costly fuels.

5.

The flywheel is necessary since it is a steady flow rotary machine
and uniform torque is produced.

Heavy flywheel is needed since the torque produced is not uniform.

6.

No internal lubrication is needed and ignition system is simple.

The lubrication system are complex and required complicated ignition
system.

7.

Part load efficiency is poor and it is less efficient.

It is efficient and their part load efficiency is high.

8.

The performance of gas turbine at high attitude is not much affected.

The output of I.C. engine decreases at high attitude due to ratified
air.

9.

The exhaust of gas turbines is free from smoke and less polluting.

The exhaust I.C. engines is more polluting.

10.

Its mechanical efficiency is high due to the absence of reciprocating
parts.

It has low mechanical efficiency due to large number of reciprocating
parts.

11.

It does not required elaborate cooling arrangements.

It requires elaborate cooling arrangements.

12.

The starting of gas turbine is difficult and needs complex
arrangements.

Starting of I.C. engines is simple.

14.

It needs low maintenance.

It needs high maintenance

15.

The expansion of gases can be carried out up to atmospheric pressure.

Gases cannot be expanded upto atmospheric pressure inside the
cylinder.

16.

It has flexibility of operation since compression, combustion and
expansion by gases takes place in separate component can be tested and
developed individually.

It does not have any flexibility of operation since all processes are
carried out in the same cylinder.

17.

From metallurgical consideration the maximum temperatures are limited
to 1300 K.

In I.C. engines the temperatures up to 2250 K can be used.