Tracking-free adaptive contact concentration photovoltaics

Abstract

Adaptive Contact Concentration Photovoltaics (ACCPV) is outlined as a scheme to access CPV efficiency improvements without mechanical tracking. This could allow CPV to play a role in applications where maintenance-free reliability and compact size are essential requirements. Conversion efficiency enhancement using sunlight concentration in multi-junction or potentially single junction solar cells due to the well-known increase in the Shockley-Quessar limit are enabled by replacing a tracking system with an array of switchable electrodes. Cell electrodes are segmented and are connected employing a switching system that adapts to sunlight conditions. Unlike CPV systems, the ACCPV concept allows for effective operation in diffuse sunlight conditions. System losses that must be considered in order to determine whether a net benefit for ACCPV exists for a given solar cell type include optical losses, series resistance losses, and Auger losses. The ACCPV concept is clearly presented and relevant system losses are discussed. A 3% absolute increase in triple junction cell efficiency is projected.