Optimal inverter and wire selection for solar photovoltaic fencing applications

Abstract

Despite the benefits and the economic advantages of agrivoltaics, capital costs limit deployment velocity. One recent potential solution to this challenge is to radically reduce the cost of racking materials by using existing farm fencing as vertical photovoltaic (PV) racking. This type of fenced-based PV system is inherently electrically challenging because of the relatively long distances between individual modules that are not present in more densely packed conventional solar PV farms. This study provides practical insights for inverter selection and wire sizing optimization for fence-based agrivoltaic systems. Numerical simulation sensitivities on the levelized cost of electricity (LCOE) were performed for 1) distance from the fence to the AC electrical panel, 2) inverter costs, and 3) geographic locations. The results showed that microinverters had better performance when the cross-over fence length was under 30 m or when the system was designed with less than seven solar PV modules, whereas string inverters were a better selection for longer fences. The cross-over number of modules depends significantly on the cost of the inverters, which is a parameter that influences the system's design. The capital costs for a fence retrofit are far less than for any form of conventional PV racking. In addition, the LCOE of the vertical fencing solar agrivoltaic system can be competitive with conventional ground-mounted solar PV for the niche of farmers. Especially, when they are located between the latitudes of 10° and 50° in either the northern or southern hemisphere, and coupled with their ancillary benefits they represent a great alternative for conventional PV systems.