Consider an InGaP/GaAs/Ge triple-junction solar cell. If the short-circuit current densities produced in each subcell are given by Jsc1 = 16.3 mA/cm2 for the InGaP top cell, Jsc2 = 17.5 mA/cm2 for the GaAs middle cell, and Jsc3 = 16.3 mA/cm2 for the Ge bottom cell, the open-circuit voltage (Voc) for this 3-junction cell is equal to 2.56 V and the FF is 84.6%. (a) Calculate the conversion efficiency of this cell under AM0 conditions (Pin = 135.3 mW/cm2 at 28◦C), (b) draw the relative spectral response curves for the top, middle, and bottom cells, and (c) plot the photo-I–V curve using the data given above for this 3-junction cell.
