Mismatch Loss for Back Irradiance in Help Menu Example

[kjs55]

bifiMMF = Bifacial Mismatch Loss Factor

bifiCoef = PV module bifaciality coefficient

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v8 Help Menu: https://www.pvsyst.com/help/project-design/bifacial-systems/bifacial-systems-results.html

v7 Help Menu: https://www.pvsyst.com/help-pvsyst7/index.html?bifacial_results.htm

Suggestion #1: I suggest updating the v8 Help Menu loss tree to represent a PVsyst v8 loss tree.

Suggestion #2: For this (v7 & v8) Help Menu example, I suggest reporting the assumption used for Bifacial Mismatch Loss Factor, for the benefit of the PVsyst user.

Comment #1: It is difficult to reproduce the "Mismatch for back irradiance" value of -2.6% on the loss tree for this example without knowing the value from Suggestion #2. My best guess is the value of bifiMMF must be 16% when using PVsyst v7. NB: I don't think the example is accurate for the updated v8 calculation method.

Comment #2: In general, I think this loss value was calculated incorrectly in v7, as = (bifiMMF*GlobBak)/(GlobBak + GlobEff). I say "incorrectly" b/c a statement on the v7 Help Menu page says, "NB: Here, the GlobBakEn is GlobBak * Bifaciality factor." I don't think bifiCoef is used in v7 (I'm running v7.2).

Suggestion #3: If I'm correct, I would suggest fixing this comment re bifiCoef in the v7 Help Menu.

Comment #3: I think bifiCoef is now used in v8 as (accurately) described in the v8 Help Menu.

The difference in results between v7 (no bifiCoef) and v8 (bifiCoef) can be significant, esp. for large values of bifiMMF.

Please confirm it.

[Michele Oliosi]

I confirm essentially what you mention. Thank you for the review 🙂
You are right, there are some updates to be done in the help. For the V8 it's simple enough, not sure whether we can change easily the v7 one.