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cdn-bacon asked

Solar Array Configuration & MPPT

I'm currently researching a project to install flexible solar panels on my boat. I had planned to use (2) 100W flex panels however they would span over a Bimini SS tube frame and from what I've read that is a huge risk for microcracking and fire potential. This brings me to version 2 of my project, to install (4) 50 W panels which I can install between frames on the soft Bimini.

Boat House Batteries: 240Ah house battery (lead-acid), 12V system.

My question: Would I be better off to put the 4 panels in series and use a 150/35 MPPT controller or put 2 in series + 2 in parallel and stick with a 75 / 15 MPPT (which I already own).

I'm struggling to understand which would be better from a battery charging stand point? Neglect any pro/cons to shading as this isn't a factor for the panel placement (either they all will be in the shade or none will). I want to get the most charge potential out of the array.

Panel Info:

Renogy panels. 50W Vmp: 20.3V, Voc: 24.3V, Imp: 2.74A, Isc: 2.75A.


screenshot-2023-03-04-at-93839-pm.png screenshot-2023-03-04-at-93852-pm.png

MPPT ControllersSolar Panel
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1 Answer
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JohnC answered ·

Hi @cdn_bacon

In your instance there's no benefit to be achieved by stringing all in series. Unless you count the avoidance of wire tees and lower Amps. That's the realm of lazy installers. :)

With 12V batts there's no point, you have plenty of panel V with 2S2P config, and already have the 75/15.

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