Energy is the ability of the body or any system to do work. Energy enables us for doing work. Energy can neither be created nor destroyed but it can be transferred from one form to another.
In recent years, mankind has been using up non-renewable sources of energy at an ever-increasing speed. Our daily lives run on a gamut of gadgets, all of which require electricity to function. Is it any wonder then that an energy crisis is staring in the face of the human race, an energy crisis of a magnitude that is difficult to even contemplate?