pvperfsolar performance modeling

Reference

API field

Albedo

Reflectivity of the ground in front of the array, per month

Unit –, 12 monthly values

What it is

The albedo is the fraction of sunlight the ground reflects. The model uses twelve values, January to December, as fractions between 0 and 1, to compute the ground-reflected light that reaches the modules. Snow raises the albedo sharply, so winter months at snowy sites carry higher values.

Typical values and how to get it

Typical values: grass and soil 0.20, weathered concrete 0.30 to 0.40, gravel 0.15 to 0.25, water 0.10, fresh snow 0.70 to 0.85. The estimate button proposes 0.20 with a snow increase in months whose mean temperature sits near or below freezing. Replace the estimate with measured values when you have them. If not given: 0.2 in every month.

References

  1. Ineichen, Guisan & Perez 1990, Ground-reflected radiation and albedo, Solar Energy 44(4) 207–214
  2. Duffie & Beckman, Solar Engineering of Thermal Processes, 4th ed., Wiley 2013

API

site.albedo_monthly