Low vs High Voltage PV

Something I’ve been wondering about now for a while: What is the advantages/disadvantages of a Victron-type MPPT with relative low voltage and something like a Goodwe with 500+V on a string?

I guess it is much simpler to “add” panels if you just string them together, but wouldn’t you also need a quite thick cable to prevent losses? Is more efficient to charge batteries with a Victron where it is more efficient to invert to AC with higher voltages?

Low voltage is great for charging batteries and storing power, but not so great in effeciency if you have to convert it to AC.

High voltage pv is the best when the majority power is used in daytime and for PV inverter setups. Converting DC voltage of 330 v and above to AC is most efficient.

That is the short of it.

And Victron’s solution to the “use most PV in daytime” would be to get a Fronius inverter?

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There’s pro’s and con’s to each approach.

High PV makes for simpler and thinner wiring. It also helps conversion efficiency in the inverter. But, the problem with long strings is shading: if one panel in a string gets shading, it affects the whole string. This is less of an issue with low PV as there are less panels in series per string

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More generically speaking: If you use most of the power during the day, you want to AC-tie your PV. Doesn’t have to be a Fronius, there are others that are supported as well. But only Fronius and ABB can be grid-limited, for technical reasons. And Fronius is such a beautiful and properly designed machine, that that is really the way you want to go…

Haha! For me it is really unnecessary, I was just wondering about it. Even with the efficiency losses of only batteries and MPPTs, I have more than enough PV available.