Modeling any bifacial solar panel array configuration on sloped terrain: Generalization using a precursor formulation

Recent numerical models assist in photovoltaic (PV) farm design and techno-economic assessment, and create digital-twins for efficient operation and maintenance. Several approaches in literature model the techno-economic output of PV-systems over horizontal surfaces. Although a considerable portion of global land is sloped, there is no model for analyzing the more recent bifacial PV-systems on such terrains. In this paper, we develop a precursor formulation to existing PV models that generalizes analysis of PV arrays on hilly terrain for any slope and orientation. The formulation includes recalculating the sun-path and irradiance for ‘an observer on a sloped surface’– these are sent as inputs to a conventional PV model. The updated inputs ensure that the overall outputs are that for a PV array on a sloped surface. Our approach therefore appends a precursor to existing PV models to design and analyze PV farms on slopes– a complete reformulation for bifacial panels on slopes, for example, would be very involved and complicated. For validation and new predicted results, we combine our precursor on the outset to a farm model (PV-MAPS). We showcase the combined model’s capabilities by demonstrating the first documented results of yield (diurnal, monthly, annual) and ground light pattern (relevant for agrivoltaics) for bifacial panel arrays on various sloped surfaces. This combined model can potentially be used for the analysis of mono/bifacial single/multijunction fixed-tilt/tracking solar farms, agrivoltaics, etc. • Novel approach to analyze bifacial PV on sloped terrain for any configuration. • Our precursor formulation generalizes existing PV models for PV-on-slope. • Our approach does not require any reformulation of existing PV models. • First predictions of yield and ground light patterns for bifacial PV on slopes. • Applications in fixed-tilt/tracking bifacial PV, agrivoltaics, etc. on slopes.