50 kW solar space power system

A photovoltaic space power system that provides improved overall operating efficiency is analyzed. The system incorporates high-efficiency, multijunction, multibandgap solar cells in conjunction with a concentrating solar array so that the cells operate at a concentration ratio of greater than 50:1 and exhibit an operating efficiency of 31% (beginning of life) at 91 degrees C. This results in an overall 50 kW system-specific power of 13 W/lb ( approximately 28 W/kg). The strawman design consists of two clam-shell-shaped wings, each 10.5 m by 10.8 m in size. Each wing has a series of small, flat mirrors mounted on a parabolic radiator structure, and the focal point is a linear solar cell cavity located along the two outer edges of the array. Solar cells of three different bandgap materials (AlGaAs, GaAs, and InGaAs) are utilized to convert sunlight to electric power efficiently, and the excess heat is collected in a heat pipe system to be redistributed to the radiator structure.