The importance of electric power cannot be denied. The convenience with which it can be transported from one place to other over long distances through a thin wire, the convenience with which it can be converted to light, heat, sound or mechanical energy with the help of simple appliances, the convenience with which it can be used simply by operating switches without any detrimental effect on the environment are some of the advantages of electrical energy.
That is why a large part of energy used by mankind is in the form of electrical energy for the generation of which other forms of energy are used, a practice which often involves much wastage. In India also the use of electric power has been rising ever since electricity generating units were first introduced in the country. From a meagre production of 5.1 billion KWH in the year 1950 it has shot up to 322.5 billion KWH in the year 1994.
Total installed electric power generation capacity in India is about 102.34 thousand megawatts. About 73% of this power comes from combustion of fossil fuels or thermal power which mostly uses coal to generate electricity. Oil contributes little of this power-generating capacity while the use of natural gas is only beginning.
Hydro-electricity contributes about 25% while nuclear power contributes about 2% only. The relative share of different forms of energy has not been the same over the past 45 years. In 1974 we had a total installed power generation capacity of about 16.66 thousand megawatts of which about 42% came from hydro-power, 54% from thermal power plants and about 4% from nuclear energy. Fig. 8.6 shows the growth of electric power generating capacity in India since 1970 with relative shares of different forms of energy.
ADVERTISEMENTS:
Both hydro-power and nuclear energy require heavy initial investment while there is a long gestation period after which the investment pays dividends. It is due to this reason that the growth of hydro and nuclear-power has been slower than the thermal power generation in our country. The share of thermal power which is most pollutive source of energy has been rising since last two or three decades.
This is not good as far as the impact of power generation on environment is concerned. Nearly 65% of the total coal production in India is used for generation of electricity. The enormous volume of oxides of nitrogen, carbon and sulphur and the amount of fly-ash discharged from power plants cause a number of problems. It is probably due to environmental problems caused by coal tired power plants that India has decided to step up the use of nuclear energy, hydro-electricity and power obtained from gas-based plants.
While nuclear energy and hydropower does not cause such environmental problems as are caused by coal, natural gas is also the cleanest and the least pollutive source of energy amongst all other fossil fuels.