What is Energy

Most of the elementary texts on energy define it as “the capacity for executing work”. This is not severely right. It will be evident from considerations of energy “quality” via the second law of thermodynamics, which while high-quality energy is capable to complete (in the situation of electrical energy) or partial (in the situation of thermal energy) transform into work, the similar quantity of energy after “degradation” has less capacity for work. Equal quantities of energy do not possess the similar “capacity for executing work”. For illustration, 1kJ of electrical energy holds more capacity for doing work than one kJ of enthalpy of superheated system at high pressure that, in turn, has more capacity for doing work than one kJ of internal energy of the sea water. However, it is the capability of energy to do work that establishes its quality.

Energy can be fashioned into mainly other needs of life. Technology, nowadays, has advanced so far that there is nearly no resource which cannot be recycled or duly replaced for, given adequate energy and the means of safely dissipating the resulting thermal and other kinds of pollution.

It is only in the past 20 years or and hence the rigorously finite nature of the (“capital-type”) energy resources, and the inevitable pollution resultant from energy utilization have start to attract severe consideration by government, industry and the public.