Power or energy resources are the basic components of economic development and the amount of energy production is often considered as an index of any country’s economic development. The importance of power resources is increasing day by day and development has nowadays become synonymous with energy use.
In primitive days all production processes which were necessary for existence of man, depended to a large extent on human muscular energy. Gradually, man used to adopt wood, wind, water, etc., for exploiting power.
It was with the onset of industrial revolution that steam engine came to be developed as a practical power plant. By 1860 coal and steam were unchallenged in their supremacy in the realm of applied power.
The introduction of petroleum as a source of power was another step in development of energy resource. Meanwhile the generation of electricity had been placed upon a commercial footing.
Electricity generated through the medium of the steam engine and steam turbine and then hydroelectricity power have come to replace to an increasing degree the direct use of mineral fuel.
The development of atomic energy and its use as power resource now has become an important source of energy in many countries of the world. Now some non-conventional sources of power have also been developed to a limited extent, such as solar energy, wind energy, tidal energy, etc.
Types of Energy Resources:
On the basis of the nature of availability and sustainability, energy resources can be classified into two types as under:
1. Non-renewable or Exhaustible Energy Resources:
Once these resources are used, they cannot be regained again; in other words, these resources are exhaustible. Such resources are coal, petroleum, natural gas and atomic fuels.
2. Renewable or Non-exhaustible Energy Resources:
These resources can be used repeatedly, e.g., running water, wind, tidal waves, solar energy, geothermal energy, biomass energy. The principal renewable resources are water, sun rays and wood.
Depending on the nature of energy, the three types are:
(a) Electrical energy
(b) Mechanical energy
(c) Nuclear energy
Another classification of energy is based on nature of use and its contribution.
The types identified are:
(i) Conventional or traditional
(ii) Non-conventional or non-traditional
The conventional or traditional sources of energy are those which are old forms and their uses were known to man for long, such as coal, petroleum, electricity, natural gas as well as nuclear power. While non-conventional energy sources are solar energy, wind energy, geothermal energy, tidal energy, etc. The present both conventional and non-conventional sources of energy.