How to simulate a PV plant with 2 different pitch inside

[jonipa]

Hello,

I am currently analyzing a 1P trackers' PV plant. One side of the plant is configured with 6m pitch while other uses 5m pitch. As I enter the 3D scene using these two tracker separation I get the following error as PVSyst is not able to compute such scenario:

In blue and yellow the two different pitch we have:

Anyone some advise on how to deal in this case?

Thanks a lot!

[dtarin]

Model these as separate variants when using bifacial modules, combine post-pvsyst. 

[jonipa]

Thank you Dtarin,

Tried to do so. Succeeded for 5m pitch trackers but when entering the 3D scene for 6m pitch I get the following error. Any thoughts on what could be happening?

[dtarin]

Under field type select horizontal N-S tracker, not the one you have selected. 

[jonipa]

Also tried so but when modifying PVSyst needs to recompute the shading factor table. Then "field type" changes to "Tracking, tilted axis automatically" again.

Still haven´t found a solution.

[dtarin]

Maybe a bug or glitch. Set it to horizontal N-S tracker in orientation menu, save the variant, close and reopen PVsyst. 

[jonipa]

Had to set it to horizontal N-S tracker and just run the simulation without computing the shading table before. The shading table was computed while simulating and could get the results report. 

But after closing the results window the error pops up again.

[Sergio Jimenez]

Hi Jonipa.

A possible way to issue this error is go to the near shading scene>constructions/perspective and select all the trackers, then go to Tools>List and Management off objects (Ctrl+G) and modify the Tilt column to 0, this will erase all the tilt from the trackers (it is an aproximation because real trackers will have a little tilt when it will be implanted in the terrain) but should allow you to use correctly the bifacial scene for the modules.

In general if the you have multiple different tilts the bifacial parameters will show you an error if the have a average difference more than 2º (this value could be seen in the advance parameters).

 

I hope this solution could help you!

[Michele Oliosi]

Hi,

22 minutes ago, Sergio Jimenez said:

In general if the you have multiple different tilts the bifacial parameters will show you an error if the have a average difference more than 2º (this value could be seen in the advance parameters).

Indeed. Actually you can change the limit to a higher value (main window > Settings > Advanced parameters), in your case 3° is ok. It doesn't change anything to the calculation. PVsyst computes the backside irradiance as if your trackers were horizontal anyways, so there may be a very small uncertainty on your yield. I would say that for 3° the uncertainty is negligible.