Energy is derived from two kinds of resources namely, renewable and non-renewable resources. For our automobiles and industries we use fuels like coal, petrol, diesel and kerosene. These cannot be renewed as easily as wind or hydro energies. It is estimated that in about two hundred years, the world's petroleum and coal resources would become completely depleted. We use electrical energy for several purposes. If the world's energy fuels are lost, thermal electricity would become impossible.

It may be argued that we can harness solar, wind and water resources for generating electrical energy. But it must be realized that conservation of electrical energy is also equally important. At present we are using electric power for entertainments like cinema and T.V. In case the monsoon fails, there would be an acute shortage of hydro-electric power.

People should realize that energy of any form should not be wasted. It should be utilized for the welfare of mankind. One cannot imagine a world starved of energy. It is our duty to think about the future generations of mankind. It is our duty to conserve energy for the future. Conservation of energy is as important as trying to find new methods of generating energy.