What parameter in 8760 to reference to identify near shading?

[Lucy]

Hello,

I want to identify near shading using the simulation output parameters in an 8760.

I have seen the column FShdBm used for this purpose. What does this parameter actually define? I see the definition on the PVsyst page but the referenced parameters in the definition are not defined (FShdBmNear shading factor on beam = BeamShd / BeamHrz). What does BeamShd and BeamHrz mean here?

How would one utilize this FShdBm to determine near shading? If this ratio falls below 1 then near shading is present? Or is this too strict and a more realistic way to use this parameter is to define when this ratio falls below 0.98(?) then near shading is present?

If FShdBm is not the best 8760 parameter to use to determine near shading, what other parameter is recommended for this purpose?

Thank you for any help.

[dtarin]

ShdLoss is the total near shading loss, which includes beam, circumsolar, diffuse and albedo components. FShdGl is the global shading loss factor, so 1- FShdGl will give the percentage value. If you wish to calculate from irradiance values, it is (GlobShd/GlobHrz - 1). If your model does not have horizon loss, GlobInc is the denominator. 

If you want to identify direct (beam) shading (i.e., from a tree or module), you would use ShdBLss or FShdBm; FShdBm is typical. How to use it depends on your application. For example in capacity testing, it is often suggested to use below 1.0; however, this may not be the best option depending on your plant, which month(s) the test is occurring, etc.