Total radiation on a tilted surface

Good afternoon,

I’m running a solar radiation simulation by Ladybug. The total radiation for the flat vertical surface is much higher than the tilted surface. That does not make sense, since the sun should be vertical on the slanted surface. Can anyone tell me why I’m getting this, please?

Angle (405.5 KB)
USA_KS_Topeka-Billard.Muni.AP.724560_TMY3.epw (1.6 MB)

I think you might be shading the test surface with the surface you input as the analysis surface? Been a while since I used Ladybug.

No, I’m Not. I tried to unplug the context but the result is still the same.

Hi -

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