S/Y Herminia going green

[Adelie]

I would go with several smaller controllers than 1 big controller.

Redundancy.
Deals with shading more easily.

[LoudMusic]

Shade on any panel will stop output for all panels in the group.

I would do multiple MPPTs. It's OK to group panels, but I would only group panels in such a way that you don't expect one of the group to receive shading while the others are exposed to sun, within reason. The cost and complexity certainly goes up, but the results are PROFOUND.

At a glance, I'd say your panel marked 1 should be on its own MPPT charger. The pairs marked 3 and 4 should have an MPPT charger per pair. The pair marked 2 (on the rails) will likely rarely have equal sun exposure. I would not group them with any other panels. OR, put an additional panel on each side and group only the panels on the same side.

My boat is a catamaran, so I have a bit more real estate for solar panels. We have six panels grouped into pairs with an MPPT controller for each pair. In this photo I've highlighted the pairings. You can see in the little blue box where the tip of the boom casts a tiny shadow onto one panel. This actually drops the output of the pair by quite a significant amount, rather than the tiny percentage that is covered. The red panels were probably making 80%+ and the yellow panels were probably making 10 to 15%. If they had all been on one controller I would have had production loss across all six rather than just the two.

Of course this does make wiring and controller mounting more complex, but you will definitely see greater performance output this way. No additional equipment is needed to have multiple charging sources. The Victron controllers periodically check the battery voltage and adjust their output accordingly. That's what the MPPT is all about.

Other than that my advice is MORE SOLAR You can never have too much. You'll always find more ways to use it We ran our salon air-conditioner for six hours on battery/solar recently.

[SoundOfSilence]

As already commented by several of you it’s better to have separate controllers to avoid the shading issue. That’s exactly what I experienced also with the 170W panels on each side. So, just as advised by LoudMusic, I removed both of them and installed 2x 120W panels on each side instead. Each side with it’s own Victron 75/15 MPPT regulator. This works considerably better. I now charge with total of 13amps/24V and also have much better performance morning and evening when only one side has sun.

I also installed the engine charging panel, but I installed it on the deck instead of on top of the sprayhood. This is a 30W panel with a Victron PWM regulator for keeping the engine battery fully charged when not using the boat.

I have changed my mind when it comes to the bimini panels because I found myself to regularly remove the bimini when sailing autumn and winter.

So all in all this setup as it is now is working well. However, I want more! And I have the 2x170w panels and the 30 amp regulator laying around. I am currently considering options for the next upgrade.

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