# Mixed Parallel and Series Solar? (1 Viewer)

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#### pat100

Three 100W panels. Two connected in series and that unit connected in parallel to the third.
Is that a Truly Wonderful (Budget-ish) Idea to somewhat alleviate the occasional problem of shading while allowing reasonable output in weak lighting? And reasonable cables. Or not … ?

#### Lenny HB

LIFE MEMBER
You can't do that, the two in series will be generating 44v and the signal one 22v. If it works it would work like two panels effectively losing the output of one.
You need to connect the series ones to a separate controller to the single panel.

The gain you get from series is so small better just to connect them all in parallel.

#### autorouter

As Lenny HB says. However four 100W panels in series/parallel would work as you describe

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#### pat100

Oh no!
My Wonderful Idea crashes and burns!
This diagram from mowgli-adventures dot com seems to agree with you.
Annoyingly, I can’t understand WHY the overall voltage drops instead of increasing.

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#### pat100

Further trying to educate myself, I found this:
which goes even further in supporting Lenny HB 's answer.

#### Reallyretired

Certainly you shouldn't do as you planned, as it won't work as per lennies post above.
However I wouldn't expect the mowgli one to be correct. I would expect the voltage and current to be that of the series pair, the parallel one would effectively do nothing to contribute. Ie. Total current would only be 4.5A at 42.2v

#### Guigsy

It's not a perfect analogy, but look at it like water flowing down a river. The volume of water per minute is the current. The drop in height over the length of river is the voltage.

If the river splits in two parallel channels and rejoins, the amount of water flowing each route can be different and the total flow can be added together (add the current). But that drop in height must be the same (same voltage).

If one section of river is after the other in series, they might have different drops in height (voltage) but the amount of water that flows (current) will be limited by the tightest section. Also, if you clog one section (i.e put it in shade) it'll reduce the flow of all the sections.

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