Vertical agrivoltaics for forage crops, animal grazing

US-based startup Sunstall has installed an agrivoltaic system based on its proprietary racking solution for vertical PV installations.

The solar array is part of a research project conducted by New Jersey's Rutgers University. The south-oriented system consists of 18 rows of 21 panels with a total output capacity of 170 kW.

“Rutgers selected ZnShine 450 W bifacial solar modules with a bifaciality rating of 70%,” the company said. “Panel orientation was varied throughout the system, allowing for a determination of the optimum orientation. Power optimizers were installed so that the output of pairs of panels could be tracked, ensuring optimal energy generation and efficiency.”

Sunstall used two different row spacings and panel mounting heights were used in the experimental design.

“Researchers will plant a forage crop in April and will start grazing beef cattle in September,” said the company. “The objective is to study the impacts of the agrivoltaic system on forage production and animal grazing, including any behavioral changes the animals may exhibit when grazing among the panels.”

According to the manufacturer, the Sunzaun racking system can ensure up to 120 cm of clearance from the ground and is able to endure a maximum wind speeds of 167 km/h. It can be deployed a flat areas and areas with a slope up to 15 degrees.

The racking system is designed to accommodate bifacial solar panels in a portrait module orientation. The design uses holes in the module frames to make a simple attachment to two piles, negating the need for a heavy racking system.

The vertical orientation of the panels leads to a grid-serving production curve, avoiding the midday production peak of traditional utility-scale arrays. It has other dual-use benefits, like providing shade to crops and saving irrigation water.