The dependence of InGaP/GaAs/Ge multi- junction solar cell model parameters on concentration and temperature are of interest to solar cell manufacturers. These parameters are related to cell processing and materials. In this work, the cell parameters were estimated by curve fitting of the experimental I-V characteristics to the single diode model equation of the multi-junction cell. The dependence of the cell parameters on light concentration and temperature is shown. Based on the estimated parameters, the performance of multi-junction cells and concentrated photovoltaic arrays under different solar irradiances and temperatures may be predicted. (C) 2014 Elsevier B.V. All rights reserved.