43% sunlight to electricity conversion efficiency using CPV

A concentrator standard test condition (CSTC) efficiency of 43.4% for the direct conversion of sunlight into electricity is demonstrated with a subunit of a concentrator photovoltaics (CPV) module. This is the highest reported CSTC efficiency for CPV applications thus far. This test device consists of a four-junction solar cell and uses an achromatic full-glass lens for concentrating the sunlight. The high efficiency is made possible by the combination of a high-efficiency solar cell (46%) and a high-efficiency lens (95%). The I-V curve of the solar cell has been measured for varying distances to the glass lens and compared with the results for a silicone-on-glass Fresnel lens. In this manner, chromatic aberration effects on solar cell performance are discussed in this study.