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what does the cell in series and active area mean in the PhotovoltaicPerformance:EquivalentOne-Diode?

asked 2020-02-02 21:23:52 -0500

yannan's avatar

updated 2020-02-05 04:54:38 -0500

in design builder, there is "cells in series "and "active area" in the one diode model of the photovoltaic generator what's the meaning of them? does the 'cells in series" means that'' there are xx (numbers) of single modules in series " ? and if I want to put them in parallel, is there any options? what is the 'active area"? for a certain sized window, when I choose different kinds of photovoltaic solar cell like ASE300-DFG/50 or BPsolar 275, the active area is not the same. and if I change the window size, the active area is not change. is the "active area" which means the for every module, the active area is xx (m^2)?

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hi julien, thank you for looking my question. but actually I have already read that webpage and my question is still unable to solve.

yannan's avatar yannan  ( 2020-02-04 22:40:58 -0500 )edit

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answered 2020-02-05 04:49:05 -0500

updated 2020-02-05 04:50:15 -0500

Note: I'm answering purely from the E+ standpoint, as I can't comment on Design Builder specific things since I don't use it.

Generator:Photovoltaic is the one that specifies which PhotovoltaicPerformance:XXX object it uses (XXX can be one of three types: Simple, Sandia, or EquivalentOne-Diode), which constitutes a single Module and the arrangement of modules in series and parallel via the Number of Modules in Series and Number of Series Strings in Parallel fields, cf I/O.

The Performance:EquivalentOne-Diode object has a field Number of Cells in Series, which isn't the same... This one is used to determine the voltage. If you want to have a lot of fun, please be my guest and read the Engineering Reference for the One-Diode model (the TRNSYS model) here. The parameter in question is $N_s$, which is referenced only at the end of the "PV Section 1: Four-Parameter Model".

$$A = \frac{\gamma }{{{N_s}}}$$

It is not super clear and I can't match it to the source code (though that's perhaps because I don't want to spend a few hours on this answer...). Anyways, in this case I think the source code is more readable: basically the number of cells in series $N_s$ (in source code that's CellsInSeries) gets multiplied by the Semiconductor Bandgap value. cf Photovoltaics::CalcTRNSYSPV

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thank you a lot! that really helps.

yannan's avatar yannan  ( 2020-02-05 05:19:19 -0500 )edit

btw, I found that it is assumed that the solar panel is installed on roof top. but in my project, I choose that in window integrated. (sandwiched structure where the solar panel in central layer and two glass cover) will that still works the same?

yannan's avatar yannan  ( 2020-02-05 19:27:20 -0500 )edit

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Asked: 2020-02-02 21:23:52 -0500

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Last updated: Feb 05 '20