[TRNSYS-users] mismatch between type 30a and type99

[Santeri Siren <santeri.siren1@gmail.com>]

Hello all,

I am trying to use type 30a to model collector array 
shading on my PV panel rows. I ran some test simulations and there seems
 to be a mismatch between type 30a and weather data file in the total 
radiation that reaches the surface. 

I set the following parameters to type 30 and to type 99 (weather data):

- slope of surface = 45
- azimuth angle of surface = 0

also in type 30:

-slope of field = 0

Then I set the row separation in type 30 to value 100 m. (there should be no shading between PV arrays)

When I log the total radiation on surface from type 30 and type 99 
there is a mismatch. The radiation level of type 30 is always a little 
lower than in the type 99. Does anyone know how this is possible? have I
 possibly made wrong connections?

Best regards. Santeri Siren

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