Agri-Photovoltaic technology allows dual use of land for tomato production and electricity generation

Agri-Photovoltaic (APV) systems combine electricity generation and agricultural production on the same land. The physiological impacts of the shading imposed on crops cultivated under such systems are not fully understood. This study evaluated the impact of APV shading on tomato physiology and productivity through two field experiments conducted in 2022 and 2023 at Bar Ilan University, Israel. Processing tomato plants (Heinz 1648, Heinz 4107) were grown in seven north-south oriented rows (T1-T7) situated between two photovoltaic (PV) panel arrays. The arrays consisted of 24 east-west-facing, single axis sun-tracking PV modules installed 1.7 m above the ground. Fruits were harvested 95-98 days after planting. Results demonstrated a strong positive correlation between total photosynthetic irradiance and tomato productivity. Shading imposed by the PV modules reduced chlorophyll content, total biomass, fruit yield, and fruit quality. Plants in the central row T4, receiving highest light availability within the APV system (1.96% less light compared to adjacent open fields), served as a control. Plants grown directly under the PV modules in rows T1 and T7 experienced the strongest shading and recorded the greatest yield losses (42% and 57%, respectively). Plants in rows with moderate shading T2 and T6 had yield losses of 13% and 20%, respectively, while plants in rows receiving near-full sunlight (T3 and T5) exhibited minimal losses (0% and 6%, respectively). Total fruit yield loss across all seven rows was 19.4% compared to conventional cultivation. Reducing the number of rows between PV modules from seven to six or five decreased yield losses to 13.0% and 7.2%, respectively, and improved the land equivalent ratio (LER). The PV systems generated ~ 29,000 kWh/1000 m² per growing season and ~ 70,000 kWh/1000 m² during the offseason. Notably, the annual net profit from tomato production under APV was 9.54 times higher than conventional agriculture.