First space concentrator prototype using III-V/Si cells

Concentrating PhotoVoltaics (CPV) can increase the efficiency of power systems in space while reducing their cost. This paper presents the first concentrator prototype using III-V/Si cells for space applications. This new approach will significantly reduce cost by concentrating sunlight then decreasing cell material, and in particular using III-V/Si triple-junction (3J) cells will allow the usage of Silicon, which is an abundant, twice less dense and low-cost material than the typically used Germanium. The efficiency of III-V/Si solar cells used is 25.7% @AM0. In our refractive module design, Compound Parabolic Concentrator (CPC), twelve 1.5x13mm2 cells are embedded in a Dow Corning® 93-500 silicone optics that provides an ∼8x concentration factor with an optical efficiency of 68%. Additionally, this linear-focus lens enables the use of single-axis sun tracking.