How is the sunpath diagram & shading factor calculated (UK only)?

Sunpath diagram

The sunpath diagram is calculated for every roof for UK customers on the page PV > Shading / snow losses:
  • From Solar API we have for every hours of the year, for every m2 on the roof if it's in shade or in sun
  • We deduce the sunPath from sun position at those hours
  • If googleAPI is not available or if the building is not built yet, we use roof orientation to define the sunpath

Shading factor:

The affected segments on the sunpath diagram get marked and counted. The shading factor is calculated 1 minus the affected segments (e.g. 1 - 15 = 0.85).