Photovoltaic solar cells convert light into electricity, but they are also PN junctions. Consequently, they exhibit a transition capacitance related to the space-charge region and a diffusion capacitance associated with the accumulation and recombination of minority carriers. In the equivalent electrical model of the cell operating in the dynamic regime, the combination of these two capacitances constitutes the cell’s parallel capacitance. Theoretically, this parallel capacitance depends on the minority carrier density (transition capacitance) and the diode current of the cell (diffusion capacitance). In this work, we establish a coupling between the parallel capacitance of a photovoltaic solar cell, the intrinsic carrier concentration, and the diode (forward) current. The results demonstrate the predominance of the diffusion capacitance over the transition capacitance under forward bias conditions.