We propose a numerical procedure consisting of a simplified physical model and a numerical method with the aim of optimizing the performance parameters of dye-sensitized solar cells (DSSCs). We calculate the real rate of absorbed photons (in the dye spectral range) by introducing a factor in order to simplify the light absorption and reflection on TCO electrode. We consider the electrical transport to be purely diffusive and the recombination process only to occur between electrons from the TiO2 conduction band and anions from the electrolyte. The used numerical method permits solving the system of differential equations resulting from the physical model. We apply the proposed numerical procedure on a classical DSSC based on Ruthenium dye in order to validate it. For this, we simulate the J-V characteristics and calculate the main parameters: short-circuit current density , open circuit voltage , fill factor FF, and power conversion efficiency . We analyze the influence of the nature of semiconductor (TiO2) and dye and also the influence of different technological parameters on the performance parameters of DSSCs. The obtained results show that the proposed numerical procedure is suitable for developing a numerical simulation platform for improving the DSSCs performance by choosing the optimal parameters. 1. Introduction The technology and materials used for the third generation solar cells give the opportunity to obtain cells with high efficiency [1–5]. The solar cells based on dye-sensitized nanostructure with mesoporous metal oxides (DSSCs) have attracted considerable attention since the work of O’Regan and Gr？tzel [6], their manufacturing being environment-friendly and energy-efficient [1, 7]. Up to now, certified efficiencies over 10% under standard conditions or even higher (12,4%) at the laboratory scale were reported [7–10]. Based on the low cost of materials and the simplicity of fabrication process, DSSC can have lower fabrication costs than conventional silicon-based solar cells. Taking into account this advantage, the improvement of DSSC parameters for making them widely used appears as a strong necessity. Further optimization of the DSSC parameters requires a better correlation between interrelated processes of transport and accumulation of electrons in the mesoporous oxide phase and recombination of electrons with electron acceptors [11]. In order to understand the different processes governing the DSSC’s mode of operation and to enhance the DSSCs performance, modeling of processes and numerical simulation of the cells were carried out
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