Effect of illumination intensity on cell parameters of a silicon solar cell

The effect of illumination intensity P in on the cell parameters of a silicon solar cell has been investigated based on one diode model. The variation of slopes of the I–V curves of a cell at short circuit and open circuit conditions with intensity of illumination in small span of intensity has been applied to determine the cell parameters, viz. shunt resistance R sh , series resistance R s , diode ideality factor n and reverse saturation current I 0 of the cell. The dependence of cell parameters on intensity has been investigated for a fairly wide illumination intensity range 15–180 mW/cm 2 of AM1.5 solar radiations by dividing this intensity range into a desirable number of small intensity ranges for measurements of the slopes of the I–V curves at short circuit and open circuit conditions. Initially R sh increases slightly with P in and then becomes constant at higher P in values. However, R s , n and I 0 all decrease continuously with P in , but the rate of decrease of each of these becomes smaller at higher P in values. Theoretical values of open circuit voltage V oc , curve factor CF and efficiency η calculated using the cell parameters determined by the present method match well with the corresponding experimental values.