Mumbai University > Mechanical Engineering > Sem 7 > Power Plant Engineering

Marks : 8M

Year: May 2016

ADVANTAGES OF GAS TURBINE POWER PLANT

The economics of power generation by gas turbines is proving to be more attractive, due to low capital cost, and high reliability and flexibility in operation. Quick starting and capability of using wide variety of fuels from natural gas to residual oil or powdered coal are other outstanding features of gas turbine power plants. Major progress has been made in three directions namely increase in unit capacities of gas turbine units (50—100 MW), increase in their efficiency and drop in capital cost, (about Rs. 700 per kW installed). Primary application of gas turbine plant is to supply peak load. However gas turbine plants now-a-days is universally used as peak load, base lead as well as standby plants.

1. It is smaller in size and weight as compared to an equivalent steam power plant. For smaller capacities the size of the gas turbine power plant is appreciably greater than a high speed diesel engine plant but for larger capacities it is smaller in size than a comparable diesel engine plant. If size and weight are the main consideration such as in ships, aircraft engines and locomotives, gas turbines are more suitable.

2. The initial cost and operating cost of the plant is lower than an equivalent steam power plant. A thermal plant of 250 MW capacity cost about Rs. 250 crores. Presently whereas gas turbines plant of that same-size cost nearly 70 crores.

3. The plant requires less water as compared to a condensing steam power plant.

4. The plant can be started quickly, and can be put on load in a very short time.

5. There are no standby losses in the gas turbine power plant whereas in steam power plant these losses occur because boiler is kept in operation even when the turbine is not supplying any load.

6. The maintenance of the plant is easier and maintenance cost is low.

7. The lubrication of the plant is easy. In this plant lubrication is needed mainly in compressor, turbine main bearing and bearings of auxiliary equipment.

8. The plant does not require heavy foundations and building.

9. There is great simplification of the plant over a steam plant due to the absence of boilers with their feed water evaporator and condensing system.