Now a day energy is a fundamental need of everyone and saving of energy is the main aim of an engineer. So more practical emphasis work should be carried out on main two approaches, to save the energy and keep the environment clean and human comfort is also a fundamental need in the present scenario. Vapour compression refrigeration system is widely used in small and big projects for cooling purpose. In vapour compression refrigeration system, Coefficient of Performance (COP) is very important factor. Keywords : Vapour Compression Refrigeration System, COP, Electricity Bill.