GaAs concentrator solar cell

Abstract
For terrestrial applications, the figure of merit for photovoltaic solar energy conversion devices is watts output per dollar of cost. AlGaAs/GaAs heterojunction cells have a very favorable watts per dollar figure of merit when used at high values of sunlight concentration. An experimental 1/2−in.−diam cell was operated in air mass 1.4 sunlight with an output power density of 4.52 W/cm2 at an effective concentration of 312 suns with a power conversion efficiency of 17.5%. The same cell was operated at 200 °C with an output power density of 3.45 W/cm2 at a 14% efficiency. The efficiency of the cell was 23% with a fill factor of 0.85 at a lower concentration ratio which is obtainable using simple concentrator schemes.