High autonomy is an important goal of most mobile systems, it can be achieved in three ways: reducingenergy consumption, increasing the capacity of batteries and replenishing battery energy over time.Another possibility comes from using an on-board generating system: in this context an embedded pho-tovoltaic system (PVS) is a feasible solution. To model the whole system and to evaluate its energy per-formance, a Simulink model in Matlab environment has been developed. Meteorological variables(radiance and ambient temperature) are essential inputs to estimate the power production of a PVS. Inthis simulator, measured, forecast as well as calculated values of radiation and temperature can be con-sidered. Once that the path followed by a mobile PVS (MPVS) is known, the Simulink tool calculates boththe energy produced by PVS and the energy consumption. Different scenarios concerning the optimiza-tion of the PV production, considering the path followed by the MPVS, its consumption and the availablesolar radiation, have been considered and simulated. This model can become a very helpful tool to esti-mate the power production of PVS applied to any mobile system in such a way not only to optimize theenergy performances but also to refine the sizing of the PVS. A mobile robot is used as test-bed.