Power Rating of a Novel Micro-CPV Module Concept and Operational Influences

Abstract

Micro-concentrating photovoltaic (micro-CPV) technology has the potential to contribute to the energy transition, facilitating the shift toward more sustainable and renewable energy sources by combining minimal carbon footprint and energy demand with low levelized cost of electricity. Micro-CPV modules utilize direct normal irradiance to convert sunlight into electrical power, necessitating precise solar tracking. The performance of these modules is influenced by their alignment toward the sun and prevailing outdoor conditions during outdoor operation. The spectral conditions, along with the ambient temperature, irradiance, and wind speed, influence the current–voltage characteristics of multijunction solar cells and the optical behavior of the lens. We have developed a novel micro-CPV module concept, which is based on low-cost and high-throughput manufacturing processes. In this work, we present a prototype module in a 10 × 6 array configuration (205-cm² aperture area, submodule class). We discuss outdoor measurements recorded over one year and the influences of various outdoor conditions. In an IEC62670-3 power rating, efficiencies of 36.0 ± 0.4% and 33.0 ± 0.4% at concentrator standard test conditions and concentrator standard operating conditions, respectively, are determined. Highest efficiencies, about 0.4% higher than at standard conditions, were attained at a more red-rich spectrum, namely at a spectral matching ratio SMR₁₂ of 0.94 ± 0.03. Using measurements at different temperatures, we show that the planoconvex silicone-on-glass primary lens has a negligible temperature dependence. Changes in the module performance over the course of one year are discussed. Despite employing commercially available low-cost components and high-throughput processes, no significant degradation was observed during the first year of operation.