A computer simulation program is adopted to assess the performance of PV pumping systems in the Kuwait climate. The program consists of component subroutines for each system component. This program takes into account the effect of solar source variations on the system performance. A new motor–pump model is developed to determine the characteristics of the pump and the motor. Comparing the present simulation results with the corresponding results using available software programs and the manufacturer data sheet validated the developed model. Based on the simulation results reported in the present study, the following conclusions can be drawn: