Bifacial model

What it is

Selects the method that computes the light reaching the rear side of the modules.

Typical values and how to get it

Chosen on the Model tab.

Values

Empty (default): Unlimited sheds 2D for fixed tilt, bifacialvf for trackers · Unlimited sheds or trackers 2D (PVsyst) = sheds_2d: two-dimensional view factors between rows of unlimited length and the ground; fixed rows, or trackers on a level axis computed at 7 rotations · bifacialvf (Marion 2017) = view_factor: NREL's view-factor model with ground strips between the rows and six cell rows on the rear side; fixed tilt and trackers · bifacialvf 1° sectors (Marion 2017) = bifacialvf: the bifacialvf model of Marion and co-workers with the field of view of each of six rear cell rows cut into 1° sectors that see the sky, the next row's front side or the ground; fixed tilt and trackers · Infinite sheds (Mikofski 2019) = infinite_sheds: the infinite-sheds model of Mikofski and co-workers: view factors from the rear face to the sky and to the lit and shaded ground between rows of unlimited length; fixed tilt and trackers

References

1. Marion et al. 2017, A practical irradiance model for bifacial PV modules, NREL/CP-5J00-67847
2. NREL bifacialvf, Bifacial PV view factor model for system performance calculation, source code and documentation (github.com/NREL/bifacialvf, bifacialvf.readthedocs.io)

API

bifacial.model