Diffuse on ground / diffuse ground fraction in bifacial

[ynesse]

Hello PVSYST community ! 

I have you are fine , I want ask about diffuse fraction on ground , how it's only depended on geometry of system as said Dr.André mermoud in FAQ simulation 

thanks

 

[Michele Oliosi]

In PVsyst, the diffuse component is considered isotropic. Therefore, it is sufficient to know for every point on the ground what portion of the sky (top hemisphere) isn't covered by other tables. This can be integrated for all positions on the ground. This fraction is purely geometrical, and is then to be applied to the total diffuse irradiance.

[ynesse]

Thanks Michele for your reply ! now I want know the diffuse acceptenance and it relationship with diffuse fraction on ground 

[Michele Oliosi]

To my understanding, the diffuse acceptance is for a point:

16 hours ago, Michele Oliosi said:

what portion of the sky (top hemisphere) isn't covered by other tables

The diffuse fraction on ground is what you get once you integrate all points of the ground.