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CONVENTIONAL SOURCES OF ELECTRICAL ENERGY

Thermal (coal, gas, nuclear) and hydro-generations are the main conventional methods of generation of Electrical Energy. These enjoy the advantages of reaching perfections in technologies for these processes. Further, single units rated at large power-outputs can be manufactured along with main components, auxiliaries and switch- gear due to vast experiences during the past century. These are efficient and economical.

These suffer from the disadvantages listed below:

1. The fuels are likely to be depleted in near future, forcing us to conserve them and find alternative resources.

2. Toxic, hazardous fumes and residues pollute the environment.

3. Overall conversion efficiency is poor.

4. Generally, these are located at remote places with respect to main load centers, increasing the transmission costs and reducing the system efficiency.

5. Maintenance costs are high.

Out of these, only two such types will be dealt here, which have a steam turbine working as the prime mover. While remaining two use Internal Combustion Engines (I.C. engines) or Gas turbine as the prime mover, and these will not be dealt with, in this introductory treatment.

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