A field-scale model for simulating the redistribution of solar radiation and water on the ground surface under solar panels in agrivoltaic systems

Agrivoltaic systems, which co-locate solar photovoltaic systems and croplands, can potentially optimize land use. However, current models cannot represent all key factors regarding solar radiation and water depth on the ground surface under solar panels. This study developed a field-scale model, AVS-Microclimate, that can represent the key factors focusing on redistributions of solar radiation, precipitation (rainfall and snowfall), melted snow (snow on panel and ground), and solar panel cleaning water on the ground surface under solar panels in agrivoltaic systems. The AVS-Microclimate model was demonstrated through three-dimensional simulations of an agrivoltaic site in Colorado, USA. The precipitation, melted snow, and solar panel cleaning water redistribution module were parameterized using observed data, which showed a strong alignment for water distribution (percent bias: −1.64%, coefficient of determination: 0.95, and Nash-Sutcliffe efficiency: 0.95). The redistribution of solar radiation and water depth (precipitation, melted snow, and solar panel cleaning water) on the ground grids varied greatly for different weather conditions, grids, and/or times (dates and times of a day). The AVS-Microclimate can assist decision-making by assessing how layouts (inclinations, azimuth angles, heights, spacing) and sizes (lengths/widths) of solar photovoltaic panels affect solar radiation and water depth under solar panels, which are critical for crop production in agrivoltaic systems.