[TRNSYS-users] Problems with Type 30a

[David Bradley]

Matias,
  You might need to be careful about the diffuse sky model that you are 
using. I believe that Type30 assumes an isotropic sky and that your 
weather component (Type15 or Type109) needs to be set accordingly. I 
doubt, however, that the sky model would explain such a dramatic drop in 
power output so I would recommend that you send your input file to your 
distributor to see if they can offer you some assistance and check to 
make sure that there is not an error in the connections.

 I might also add that calculating the effects of shading on a PV is a 
bit complicated. The problem is that if you completely shade even a 
small part of a PV array, the shading creates an open-circuit in the 
array and power production drops off very dramatically. Type30 assumes 
that there is a linear behavior between shading and thermal performance 
(it was written with rows of solar thermal collectors in mind) and PV 
shading is very non-linear. If you have access to the TESS Green 
Building Library, there is a PV shading component in there that uses 
basically the same algorithms as Type30 but makes some improved 
assumptions about the effect of the shading on the PVs. It also allows 
some configurations if the PVs are oriented on a vertical field instead 
of on a horizontal field.

Kind regards,
 David


Matias Garcia wrote:
> Hi!
> I want to see the effect of the shadows produced by the collectors in 
> a photovoltaic installation. When I connect the type 30a to the PV 
> array the power I obtain from the array is incredible small, it could 
> have some common sense if I multiply it by ten. If I introduce in type 
> 30a a very big distance (800m) between the modules, the problem is the 
> same and the power comes very small (divided by ten). Only without 
> type 30a I obtain a normal power production.
> Can any one help me?
> I am new here so, hello to everyone!
> ------------------------------------------------------------------------
>
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Thermal Energy System Specialists (TESS), LLC 
David BRADLEY                      22 N. Carroll Street - Suite 370 
Partner                            Madison, WI 53703 
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