Applying Photovoltaic Principles to the Design and Development of an Automated Solar Tracker

Abstract

Solar tracking systems dynamically adjust photovoltaic panel orientation to maintain optimal sun alignment, potentially enhancing energy harvest compared to fixed installations. This study investigates the design, construction, and performance validation of an automated single-axis solar tracker incorporating light-dependent resistor (LDR) sensors, servo motor actuation, and Arduino-based control. We quantified photovoltaic cell response with three key parameters: angle of incidence, spectral wavelength, and tracking versus static operation. The angle of incidence of incoming light was found to greatly affect the power output of the solar cell, which steadily decreased as angle increased; an orthogonal 0° had the highest output. We characterized the output of the solar cell on the spectral wavelength incident on the setup (630nm, 530nm, and 470nm wavelengths), and found discrepancies in the output power favoring longer wavelengths. A laboratory conducted experiment demonstrated nearly eight-fold power improvement (7.9 mW tracked versus 1.0 mW static). The field experiment that is conducted under California sun conditions over a full day (7:30 AM to 6:00 PM) revealed 53.92% increase to average power output (26.32 mW tracked versus 17.10 mW for static panel matched to altitude angle 36.95°). The tracking system maintained superior performance throughout the day graph other than at solar noon, where the power values converged to around the same magnitude as the sunlight reached the point where it was directly incident upon the static solar cell. Temperature control throughout experiments eliminated thermal effects as confounding variables. These findings establish that automated solar tracking provides significant energy harvest enhancement.