Designing agrivoltaic systems for plant protection

This study investigates how the geometrical design of agrivoltaic systems, which integrate photovoltaic panels on agricultural surfaces, influences plant temperature during three typical weather-risk events: white frost, heat waves, and windy atmospheric conditions. It uses a novel numerical approach based on the dynamical coupling of a soil-plant-atmosphere continuum model and a computational fluid dynamics solver. First, a pilot-scale agrivoltaic system is numerically reproduced, and the evaluation of simulated versus measured plant temperatures over six diurnal cycles demonstrates the robustness of the proposed approach, with errors ranging from 1 °C to 3 °C for nighttime and daytime conditions, respectively. Then, the typical weather-risk events are numerically generated to emulate the effect of six geometrical designs of agrivoltaic systems on the microclimate and compare it to a baseline condition without panels, standing as control zone. The results reveal that the spatially averaged plant temperature in the simulated agrivoltaic zones often differs by more than 5 °C compared with the control zone. More presicely, the elevated design where agrivoltaic panels are 5 m above the ground is shown to protect the most against white frost and heat (up to 3 °C and 4 °C, respectively) by reducing the sky-plant view factor. Conversely, the vertical agrivoltaic design has the strongest impact under windy atmospheric conditions (4 °C), as it can break the airflow thereby limiting convective and evaporative transfers. All in all, this work highlights the importance to tailor agrivoltaic designs to the predominant stresses plants are likely to face, in order to maximize plant protection and, consequently, agricultural yield.