Abstarct: Arid and semi-arid of Iran country have made the use of cooling devices inevitable. More than 50 percent of domestic consumers use evaporative coolers to cool their house. Due to the low efficiency of the driving electric motor of these types of coolers and a large number of consumers, the strucure change of the electric motor and increase of its efficiency are vital. AFPM motors can be a suitable alternative for induction motors used in evaporative coolers due to appropriate performance characteristics such as high efficiency and power density. Because of the use of permanent magnet materials and power electronic devices in these types of motors, the manufacturing costs of evaporative coolers increase. Considering that one of the main factors in executable of any plan is its initial cost and profit, in this thesis it is tried to introduce the methods of returning primary capital to replace the induction motor used in evaporative coolers with AFPM motor. According to the conducted surveys in this field, four methods for returning primary capital have been introduced as follows: 1- Reduction of peak load caused by each household, 2- Reduction of environmental pollution, 3- Reduction of consumed kWh of each household and 4- Increasing the comfort level of consumers Then the amount of increasing initial cost of evaporative cooler manufacturing due to the use of AFPM motors and the amounts of returning initial capital by each of four introduced methods are calculated that the difference between these two is the obtained profit. Maximizing the obtained profit as the optimization objective function is considered in the design of an AFPM motor to maximize the obtained profit from this replacement. By calculating the profit obtained from these four methods, it is observed that at the end of each year a significant profit obtained for households that have replaced their common evaporative coolers with improved evaporative coolers.