Module Technology for Agrivoltaics: Vertical Bifacial Versus Tilted Monofacial Farms

Agrivoltaics (AV) is an innovative approach in which solar photovoltaic (PV) energy generation is collocated with agricultural production to enable food-energy-water synergies and landscape ecological conservation. This dual-use requirement leads to unique cooptimization challenges (e.g., shading, soiling, and spacing) that make module technology and farm topology choices distinctly different from the traditional solar farms. Here, we compare the performance of the traditional optimally titled North/South (N/S)-faced monofacial farms with a potential alternative based on vertical East/West (E/W)-faced bifacial farms. Remarkably, the vertical farm produces essentially the same energy output and photosynthetically active radiation (PAR) compared with the traditional farms as long as the PV array density is reduced to half or lower relative to that for the standard ground-mounted PV farms. Our results explain the relative merits of the traditional monofacial versus vertical bifacial farms as a function of array density, acceptable PAR deficit, and energy production. The combined PAR/Energy yields for the vertical bifacial farm may not always be superior, it could still be an attractive choice for AV due to its distinct advantages such as minimum land coverage, least hindrance to the farm machinery and rainfall, inherent resilience to PV soiling, easier cleaning, and cost advantages due to the potentially reduced elevation.