API field
Ground albedo (bifacial system)
Albedo of the ground under the array; empty = site albedo
Unit – / 12 monthly values
What it is
The reflectivity of the ground the rear side sees, either one value or twelve monthly values. Empty uses the site's monthly albedo.
Typical values and how to get it
About 0.2 to 0.3 for grass or soil and about 0.6 to 0.8 for a white membrane; from an albedometer measurement under the array, else the site albedo.
API
bifacial.albedo