2021/07/06 by Kevin Krisciunas, K. Krisciunas, Krisciunas, Kevin
Computer Science · Energy · Engineering · Physics and Astronomy · #FOS: Physical sciences #Instrumentation and Methods for Astrophysics (astro-ph.IM) #Photovoltaic System Optimization Techniques #Solar Radiation and Photovoltaics #Solar Thermal and Photovoltaic Systems #astro-ph.IM #solar cell performance optimization
paper · pdf · doi:10.48550/arxiv.2107.02876
28 pages, 11 figures
openalex publication_date 2021/07/06 · arxiv created 2022/06/08 · arxiv updated 2022/06/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We characterize the performance of a fixed grid of solar panels on the basis of data taken under clear sky conditions over 12 months. We confirm that the power output is linearly proportional to cos(theta), where theta is the angular difference of direction toward the Sun and the vector perpendicular to the panels. In order to confirm this we applied methods from astronomical photometry reduction. From late March through August we find that the median effective atmospheric extinction term is 0.145 mag/airmass. From October to mid-March the median extinction term is 0.081 mag/airmass. The proportionality "constant" scaling cos(theta) appears to be seasonally dependent, with the smallest scaling factors occurring when the extinction term is largest. Finally, we find that extinction-corrected power often underperforms the linear relationship late in the morning or early in the afternoon. This is most likely because the efficiency of solar panels depends on their operating temperature, and the panel temperature increases over the course of time on a sunny day.