Structural optimisation of free-swinging agrivoltaic fences

Abstract

Agrivoltaic fences enable farmers and ranchers to produce energy while maintaining profitable agricultural activity. They consist of vertical posts between which vertical solar panels are mounted. A significant part of the structural costs of these frames comes from their high wind load, which requires large diameter posts, often with wind bracing, and substantial foundations. This research focuses on free-swinging agrivoltaic fences, a new concept that allows panels to 'float' in the wind, an akin to clothes drying on a clothesline. In other words, the panels are suspended from hinged joints, allowing them to swing in strong winds. This study demonstrates that the internal forces in the posts are more than 8 times lower than those induced by fixed vertical panels and scales various parameters involved such as the height of the system, the wind force acting on the panel, its dimensions and weight. The results highlight the fact that the maximum forces generated in the posts of such a system are independent of the wind model considered and can be determined using only the weight of the panel, the height at which it is fixed and the position of the wind pressure on the panel's surface. Finally the study provides a much more reliable and safer design methodology than that used for vertical fixed panels. Design curves are established to provide designers with guidelines on what type of section to use, whether it is steel or timber.