By Andi Anderson
A research team led by scientists from Purdue University has developed a groundbreaking model designed to optimize corn yield in agrivoltaic systems, which combine agriculture with solar energy production.
This innovative approach uses a spatiotemporal shadow distribution (SSD) model to balance crop growth with solar power generation, ensuring that both can be maximized effectively.
The model is built on the Agricultural Production Systems Simulator (APSIM) plant model, which operates with finer temporal resolution and has been validated by existing literature.
The SSD model considers the shadows cast by photovoltaic (PV) panels, integrating data from the National Renewable Energy Laboratory (NREL) to simulate real-world conditions. These data were then calibrated and validated through field experiments conducted at an agrivoltaic farm at Purdue University in West Lafayette, Indiana.
In the field experiment, two different PV panel arrangements were tested: one with 300 W modules placed adjacent to each other, and another with 100 W modules arranged in a checkerboard pattern.
Both setups utilized single-axis trackers and were tested from April to October 2020. The research team collected data from 12 plots, comparing corn yields from areas with and without PV panels.
The results showed that corn yield in the area without PV panels was 10,955 kg/ha, while the yield in the PV area was 10,182 kg/ha. These findings closely aligned with the model’s predictions, which estimated yields of 10,856 kg/ha for the no-PV area and 10,102 kg/ha for the agrivoltaic field.
Further analysis using the model explored the impact of various factors on corn yield, including tracker height, distance between PV arrays, panel angle, and the timing of the tracking system’s activation.
One key finding was that reducing the tracker height, as long as it does not hinder farm machinery, had a minimal impact on overall yield. However, variability in yield between corn rows increased as the tracker height decreased. Additionally, increasing the distance between PV rows beyond 9.1 meters did not lead to significant yield improvements when total land power output was maintained.
The researchers also discovered that implementing anti-tracking (AT) during solar noon could increase corn yield by 5.6%, though this benefit must be weighed against a reduction in solar power production.
This research, published in Cell Reports Sustainability under the title “Optimizing corn agrivoltaic farming through farm-scale experimentation and modeling,” offers valuable insights for improving the efficiency and effectiveness of agrivoltaic systems. The study was conducted in collaboration with academics from Denmark's Aarhus University, further emphasizing the global interest in sustainable farming practices.
Photo Credit: purdue-university
Categories: Indiana, Education