A condenser is a two-phase flow heat exchanger in which heat is generated during condensation process which is removed from the system by a coolant. Here key point is energy destruction which always associates with condensation due to difference between condensate temperature and inlet CW temperature. Thus it is very crucial to operate the condenser efficiently under the various operating condition to minimize the energy destruction and enhance energy efficiency. This paper focus on optimization of energy destruction with respect to different condenser pressures, mass flow rate of steam and inlet CW and environment temperatures with strictly taken into account that condensation of the entire vapor must within condenser. To find out the overall heat transfer coefficient, Bell Delaware method is used; all relevant geometric dimensions required are also mathematically found. In first case, it is found that energy destruction decreases with decrease of condenser pressure for given atmospheric condition and inlet CW temperature is also decreases accordingly. So it is better to operate the condenser at as low as possible pressure. In second case if steam mass flow rate increases then energy destruction is also increases and the inlet CW temperature required to be decreases to satisfy the condition of condensation of entire steam. Finally in third case, if coolant flow rate increases for given atmospheric temperature, energy destruction reduces which leads to increases inlet CW temperature.