Design improvements for the polyhedral specular reflector spectrum-splitting module for ultra-high efficiency (>50%)

Abstract

A spectrum-splitting module design, the polyhedral specular reflector (PSR), is proposed for ultra-high photovoltaic efficiency (>50%). Incident light is mildly concentrated (≤16 suns) and subsequently split seven ways by a series of multilayer dielectric filters. The split spectrum is directed into compound parabolic concentrators (CPCs) and each concentrates a given slice of the spectrum onto one of seven subcells for conversion. We have recently made significant improvements to the design, such as vertically stacking each submodule and rearranging the subcell order to increase the optical efficiency of the design. We optimize the concentration and composition of the parallelepiped prism (hollow vs. solid) and model designs with >50% module efficiencies including optical and cell nonidealities.