Solar Panels Controller Sorry

Stoshak

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I propose to fit solar panels on the hatch garage, and I understand that two are better than one from the point of view of shading.

But do I need two controllers, or do both panels feed into one controller?

Google has not provided the answer, so can someone help, please?
 
I propose to fit solar panels on the hatch garage, and I understand that two are better than one from the point of view of shading.

But do I need two controllers, or do both panels feed into one controller?

Google has not provided the answer, so can someone help, please?

Two into one is fine. Parallel for a PWM or simple switching controller, series for an MPPT one.
 
Two into one is fine. Parallel for a PWM or simple switching controller, series for an MPPT one.

If two are connected in series should they be fitted with bypass diodes to minimise the effects of one panel being shaded?
 
Two into one is fine. Parallel for a PWM or simple switching controller, series for an MPPT one.
That's how my panels are set up - I got two 20s rather than one 40 because of the risk of shading. They've worked fine for the last couple of years. Stoshak, I have exactly the setup you're planning. PM me if you'd like to see what I've done or discuss it further.

If you have separate starter and domestic batteries (or banks) consider a dual charger. Mine pushes 90% of the output into the starter battery until it burps, then turns its attention to the domestic. That way, if the lights ever get dim, at least I can start the engine.

If two are connected in series should they be fitted with bypass diodes to minimise the effects of one panel being shaded?

I'm pretty sure my panels have a diode each but, while a shaded panel won't be pushing many amps out, I don't think it'll bleed power from the sunny one.
 
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I have 4 x 20w panels in Parallel through an MPPT controller. It seems to work well why would it be better in series.
 
I have 4 x 20w panels in Parallel through an MPPT controller. It seems to work well why would it be better in series.

I think this may be because an MPPT controller can usefully work with higher voltages, so if your panels are individually only putting out say 12v each, a normal controller couldn't use that power, but an MPPT would be able to convert it to the appropriate charging voltage. I stand ready to be corrected!
 
Note that the larger sizes of Spectra semi flexible panels are already wired in two separate circuits.If the garage is curved you may well be using these.
 
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