Multi-year field trials in Italy show that agrivoltaic systems can support healthy potato yields without major losses. Strategic sun protection and dynamic light management during critical growth phases proved to be the key to maintaining productivity.
A research team led by Italy’s Catholic University of the Sacred Heart has completed a four-year field experiment on potato cultivation under agrivoltaic (APV) systems. The study analyzed how potato yields and traits respond to different shade patterns. “The potato crop, despite its global importance, is relatively underrepresented in agrivoltaic research, with only a handful of studies available,” the team said.
“The novelty of our research lies in combining multi-year field data with a physiological interpretation of crop responses under agrivoltaic conditions,” said corresponding author Michele Colauzzi. pv magazine. “Rather than just looking at yield reduction as a function of average shade, we focused on how the timing and distribution of light affects crop development. This allowed us to identify critical growth stages, such as tuber initiation, where light availability plays a key role in determining final yield.”
A surprising finding, according to Colauzzi, was that the yield reduction was not proportional to the overall decrease in radiation. “Moderate shade had limited effects, while higher shade levels caused a sharp decline in yield,” he said. “This indicates a ‘tolerance zone’, outside of which crop performance declines significantly. Shade timing was more important than the seasonal average, highlighting the role of crop physiology in the design of the APV system.”
The experiments took place in a large commercial APV facility in Borgo Virgilio, northern Italy. The solar park uses a REM Tec’s Agrovoltaico two-axis tracking system, equipped with 325 W monocrystalline silicon modules with an efficiency of 17%, with a total installed capacity of 2,147 MW.
Five shadow scenarios were tested in four independent field trials between 2021 and 2024. The full light scenario (FL), which represents standard potato cultivation without shade, served as a reference. Scenario ST1 corresponded to Agrovoltaico’s unchanged tracking system. In scenario ST2-2021, a 5 m x 12 m high-density shade net was installed horizontally beneath the PV panels, while in ST2-2022/2023 the team installed a 3 m x 4 m wooden frame covered with black polyethylene over the panels.
In 2024, an Anti-Tracking (ST1+AT) scenario was tested to reduce shading during the critical tuber initiation phase by rotating the secondary axis 90° against the sun. After tuber initiation was completed, the monitoring system resumed normal operation.
During the tests, the researchers monitored weather variables, including temperature, rainfall, radiation, humidity and wind. Solar radiation and shade patterns at ground level were mapped to quantify shade depth across the plots. Potato growth was monitored via plant height, leaf area index (LAI) and specific leaf area (SLA). At harvest, the salable yield (t/ha), tuber number per square meter, tuber size distribution and dry matter content (DMC) were measured.
The mean shadow depth for ST1 averaged approximately 20% per year. ST2 reached 37.5% in 2021 and 42.3% in 2022-2023, while ST1+AT averaged 17% in 2024. Marketable yields reflected these shade levels: 51.5 t/ha under full light in 2021 falling to 38.9 t/ha under ST1 and 28.0 t/ha under ST2. In 2022, yields decreased from 38.0 t/ha (FL) to 29.9 t/ha (ST1) and 24.6 t/ha (ST2). In 2023, yields were 27.4 t/ha (FL) and 16.1 t/ha (ST2). In 2024, yields under FL (30.3 t/ha) and ST1 (29.9 t/ha) were similar, with ST1+AT achieving 32.7 t/ha.
“The standard sun tracking configuration (ST1), with little seasonal shade (about 13%), caused limited yield damage (average -12%), while the higher shade configuration (ST2) led to reductions of more than 30%,” the researchers concluded. “AT management during early tuber development partially mitigated yield losses, demonstrating that dynamic light management can help balance agricultural productivity and energy generation in APV systems. Weibull-based modeling of tuber size distribution indicated a consistent shift toward smaller tubers under increasing shade, while tuber dry matter content remained stable.”
The research work was presented in “Potato production in agrivoltaic systems in northern Italy: a four-year case study on array arrangement, shading patterns and yield response”, published in Smart agricultural technology. The research team consisted of scientists from the agrivoltaic technology company REM Tec.
Recently, researchers from the University of Florence analyzed the impact of an agrivoltaic facility on potato production using a modeling framework that combines PV energy production, high-resolution shadow mapping, process-based biomass growth and economic analysis. Their findings showed that agrivoltaic systems can reduce potato yields by up to 15% compared to full light cultivation. However, early season moderate shade was found to slow soil moisture depletion, increase biomass accumulation, and improve water use efficiency.
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