Temperature coefficient of multijunction space solar cells as a function of concentration

Measurements of multijunction space solar cells were taken as a function of temperature for low intensity operation (down to 0.02 suns), and also at high intensities (up to 60 suns). Cells from two vendors were tested. The effect of intensity on the measured temperature coefficient was analyzed. The temperature coefficient of the short circuit current was directly proportional to the intensity, while the temperature coefficient of the open circuit current decreased proportionally to the open circuit voltage. Commercial triple-junction space cells were tested to temperatures as high as 400°C, showing a slight deviation from linear performance but no catastrophic degradation.