Agrivoltaic systems: Trade-offs on microclimate, physiology, yield and canopy thermal-spectral maps
Maryam Rahimi Jahangirlou, Johannes Wilhelmus Maria Pullens, Magnus Kamau Katana Lindhardt, Yannick Valentin El Khoury, Vita Antoniuk, Kiril Manevski, Carl-Otto Ottosen, Uffe Jørgensen
Abstract
CONTEXT Competition between solar energy deployment and cropland use is intensifying. Agrivoltaics (APV), which co-produces food and electricity, modifies the microclimate between panels, influencing plant physiology, yield, and quality. Comparative field-scale evidence across different PV configurations and crops is required to optimize APV design for both productivity and resilience. OBJECTIVE To evaluate how APV-induced microclimate alters crop physiology, canopy traits, yield, and quality over two years, with interannual weather variability and to determine system- and crop-specific responses that inform climate-smart APV design. METHODS Two bifacial APV systems (25° south-tilted and vertical east–west) were compared with an open-field reference in rotations of winter wheat, grass–clover, and soybean in a temperate climate. Measurements stratified by panel-relative zones (shaded, semi-shaded, open) included: (i) microclimate (air temperature, humidity, wind speed) used to derive VPD and ET₀; (ii) leaf traits (temperature, stomatal conductance, Fv/Fm) at key growth stages; (iii) UAV-based thermal multispectral maps (NDVI, surface temperature); (iv) yield and quality at harvest. RESULTS AND CONCLUSIONS Grass–clover biomass was consistently higher between vertical panels (5.8 and 14.8 t/ha in 2023 and 2024) than between tilted panels (4.3 and 14.0 t/ha, p < 0.01), and comparable to open field. Wheat yields were similar across treatments in the dry year 2023 (3.7–4.7 t/ha), but declined between panels in the wet year 2024 (6.0–6.2 vs 7.0–7.1 t/ha in reference). However, wheat quality improved under APV in both years: grain protein (9.5–9.8 % vs 8.1 %) and gluten (17–18 % vs 15–16 %, p < 0.01). Soybean yields were reduced in APV zones (3.25–3.50 vs 4.91 t/ha, p < 0.01), although dry matter content remained ∼35 %. APV reduced mean wind speed (vertical 1.19, tilted 1.58 vs reference 2.17 m/s) and ET₀, and lowered canopy/leaf temperatures while increasing Fv/Fm. NDVI and thermal maps partly reflected these physiological patterns. Responses varied with interannual weather: APV conferred greater shelter benefits in the dry year, particularly in the vertical system. SIGNIFICANCE By linking leaf-level physiology to canopy and landscape indicators, this framework enables systematic APV assessment across weather conditions and designs. Findings highlight vertical APV as a promising configuration for stabilizing yields under drought, supporting evidence-based decisions for land-efficient, climate-resilient food–energy systems.