Power efficiency analytical modeling of the tri-layer solar cells based on energy gap

The semiconductor materials adapted to the tropical zone according to their optoelectronic properties and especially their gap energies and their molar composition were chosen. To cope with the low efficiency encountered in single junction solar cells, these materials were used in the choice of a geometry of a Ga0.67In0.33P/GaAs/Ga0.70In0.30As tri-junction solar cell adapted to our area study. We have made the optimization of this solar cell efficiency by taking into account only the gap energies of the materials constituting the sub-cells and the temperature of the cell as the only design variables while setting the other parameters. An analytical model has been proposed for this purpose to determine the output parameters of the cell namely: the open circuit voltage (Voc), the short circuit current density (Jsc), the fill factor (FF) and conversion efficiency (ƞ).A conversion efficiency found after optimization of the tandem cell was reported and compared to that of literature. The influence of the temperature on these parameters was studied and a coefficient of variation of the voltage as a function of the temperature of - 6.7mV /° K and the decrease of the efficiency (ƞ) of - 0.072% / °K for the tri-junction solar cell were found.