The current-voltage (I-V) curve for a PV cell shows that the current is essentially constant over a range of output voltages for a specified amount of incident light energy. Figure 1: Typical I-V Characteristic Curve for a PV Cell Figure 1 shows a typical I-V curve for which the short-circuit. The output power of the PV cell is voltage times current, so there is no output power for a short-circuit condition because of VOUT or for an open-circuit condition because of IOUT= 0. Above the short-circuit point, the PV cell operates with a resistive load. The efficiencyof a PV cell is the ratio of light energy falling on the cell to the light energy that is converted into electrical energy. It is expressed as a percentage, as shown in the. The fill factor of a PV cell is an important parameter in evaluating its performance because it provides a measure of how close a PV cell comes to providing its maximum theoretical. Several factors determine the efficiency of a PV cell: the type of cell, the reflectance efficiency of the cell's surface, the thermodynamic efficiency limit, the quantum efficiency, the maximum power point, and internal resistances. When light photons strike the PV.