Distributed generation is an approach to power generation by low capacity systems. In this paper small wind turbines are investigated as distributed generation systems used to satisfy household/commercial and agricultural sectors demand. This paper explains a decision-making process during which consumers can easily define appropriate Wind Energy Conversion System (WECS), considering economical accordance by the amount of power consumption and climate condition of installation place. Rotor diameter and turbine hub height are distinguished as two main parameters affecting WECS, referring to consumption rate and climate circumstances of the place. Mathematical relation between Cost Per Unit (CPU) of generated power and these two, is determined with high correlation coefficient which will be applied during the process to easily nominate different WECSs. Having the amount of costs paid by a family per 1 kWh of electricity consumption, WECS characteristics can be conveniently specified using this relation. To examine the influence of each of the above parameters and increasing the validity of the results, turbines with different rated powers and hub heights, are used in four regions with various geographical circumstances. © Springer International Publishing Switzerland 2014.