Using the concepts of changes in state and transferability explaining the importance of energy Solution the energy transfer can be explained using the example of heat transfer, the change in the state of energies from one state to another like from mechanical energy into the electrical energy in turbines. The change of chemical energy to light or sound energy in the crackers. Change of solar energy to the electrical energy in modern solar plants.Change of wind flow energy in the electrical energy. Change of hydro energy in the electrical energies in hydro projects. this transferability of energy explains the importance of energy on wide spectrum.It further states the principle of law of conservation of the energies. .