Balancing energy generation and crop productivity: A modeling and validation study on alfalfa agrivoltaics

Agrivoltaic systems (AVS) offer a promising solution to land-use competition by combining renewable energy production with agriculture. This study applied an integrated modeling framework linking the three-dimensional radiation and crop growth model GroIMP with PVsyst to optimize row spacing in a fixed AVS cultivating alfalfa (Medicago sativa L.). Simulations evaluated pitches ranging from 4 to 16 m to explore trade-offs between energy yield and biomass production. Dense configurations, such as 6 m spacing, increased energy output by 20% relative to the 8 m baseline with minimal impact on biomass (1% loss), whereas wider spacing, such as 10 m, enhanced biomass by 40% at the expense of a 19% reduction in energy. In conditions of limited water availability, as represented by half of the observed precipitation in 2023, the shading provided by AVS partially offset the drought stress, thereby transforming the energy-biomass tradeoff into a synergy. The 10-meter pitch resulted in a +12% biomass gain relative to the full-sun (FS) control, with a maximum gain of +14% observed at 16 meters. These findings demonstrate that AVS can simultaneously optimize renewable energy generation, crop productivity, and climate resilience, and that the proposed integrated framework provides a robust tool for guiding system design under variable environmental conditions.