Orientation error for bifacial panels on carport

[AHMED]

Hello, I'm working on ONE table on top of carport

Bifacial panels together with no distance in between therefore I consider as ONE shed 

what could be the right pitch value here?. it's one table!

I tried zero but system gives an error and when I try 2.3m as space from one panel end to next one

I find system later changes pitch value to 22 or 24 m !

also after running the simulation I find almost no impact of bifacial panels on output kw! although they're 2.5m high from ground with 0.3 albedo

 

Anyone could help and advice what would be the right value for pitch and band width in this case?

How to resolve this. Thanks

 

Pls see attached images 

 

[Linda Thoren]

Hi Alex,

The Unlimited Sheds field type is aimed for large regular systems with several rows assumed to be sufficiently long (unlimited) sheds so that we can neglect the edge effects. For only one table you must choose the field type Fixed tilted plane.

Indeed it is not possible to simulate a bifacial system with a single row, though this is on our roadmap. The bifacial calculation in PVsyst is based on a 2 dimensional representation, calculating how much irradiance is falling between the tables and how much will be scattered up on the back side, thus there has to be a pitch.

A possible workaround is therefor to create a 3D scene with your table and then duplicate this scene further away so that PVsyst can detect a pitch. Verify that the tables are well aligned so that indeed PVsyst detects the pitch in bifacial window.

Note that the amount of tables in the 3D scene will be double what you have defined in the system and this will create a warning. You can increase this limit in the advanced parameters. In the first PVsyst welcome window, click “Settings” and “Edit advanced Parameters” and find the parameter that triggers the error message – “Shadings: absolute maximum shading/field area ratio”. This will allow you to run the simulation

 

Kind regards

[AHMED]

 

Thanks Linda for your prompt response,

Appreciate that you've clarified it is not possible to simulate a bifacial system with a single row at present ) : 

I will go with that possible workaround you've kindly suggested. Thanks a lot and best regards 

[AHMED]

How about this scenario; consider my shed as very long shed and ignoring the reflection from tow side of the table 3,4. see attached image.

and regarding the pitch I use respectfully high value ( let say 10m ), so system read maximum value of irradiance reflection from both sides 1 and 2 towards panels backside.

Would this works? so I could simply use Unlimited Sheds field type and avoid making 3D and no need for reset error message.

 

What do you think?

[Linda Thoren]

Hi,

Indeed if you have no other shadings this solution would give a rather representative scenario of what you wish to simulate. 

[AHMED]

Thanks 👍