In this work, an investigation and evaluation of harvested energy by solar air collector equipped with offset strip fin absorber plate is carried out under different climate conditions of Algeria. The so called isopleths maps of harvested solar energy by solar air collector of typical main city each representing a given climate region (Alger, Tlemcen, Chlef, Batna, Ghardaïa, Adrar and Tamanrasset) are elaborated. A Matlab code has been developed to solve the mathematical model and determine isopleths maps in order to clearly identify strong contrasts between different climate regions. The simulation results are presented for each city and was found that the studied solar air collector is competitive in all cases and even more economically beneficial in case of hot regions. These results stimulate our desire and drive our ambition to implement this solar air collector system for drying process through all regions especially in hot seasons.