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Agrivoltaic systems, which achieve sustainable food and energy co-production (SFE) by installing photovoltaics (PVs) on farmland, offer a climate-resilient solution for meeting ”full Earth” needs while adhering to land limitations. However, limited research on major row crops, such as corn (Zea Mays), constrains the widespread adoption of agrivoltaics. To bridge this research gap, a two-step process was executed. First, extensive corn growth data was collected from neighboring regions, specifically segregating ”with-PV” (shaded) and ”without-PV” (unshaded) areas under real farming conditions. Using data from unshaded areas, the APSIM plant model was calibrated. Subsequently, an analytical shadow model was used to compute the spatiotemporal shadow distribution (SSD) for each row of corn between PV panels. This SSD data helped validate the APSIM model using the experimental corn yield data from shaded areas. 

Abstract — Photoluminescence Excitation Spectroscopy (PLE) is a contactless characterization technique to quantify Shockley-Reed-Hall (SRH) lifetimes and recombination velocities in direct band gap experimental semiconductor materials and devices. It is also useful as to evaluate surface passivation and intermediate fabrication processes, since it can be implemented without the need for development of effective contact technologies. In this paper, we present a novel experimental PLE system for precision-based quantification of the aforementioned parameters as well as a system for which absolute PLE characterization may occur. Absolute PLE measurements can be used to directly calculate VOC for new photovoltaic (PV) material systems and devices. Key system capabilities include a continuous excitation spectrum from 300 nm –1.1 μm, automated characterization, up to 1 nm wavelength resolution (up to 60x higher than prior work), and a reduced ellipsometry requirement for post-processing of data. We utilize a GaAs double heterostructure (DH) and an InP crystalline wafer as calibration standards in comparison with data from an LED-based PLE to demonstrate the validity of the results obtained from this new system. Index Terms – photovoltaic cells, photoluminescence, charge carrier lifetime, gallium arsenide, indium phosphide.