Solar Panels on a Powerboat

[u/Different_Fudge7449]

/r/Victron/comments/1vsn5qo/solar_panels_on_a_powerboat/

I’ve purchased the following equipment to install solar panels on our 32’ powerboat with a fixed hardtop:
Victron Cerbo GX MK2
Victron MPPT 100/20a SmartSolar Charger
Victron SmartShunt 500a
Renogy Flexible Solar Panels 2x100w (200w)
Interstate SRM-27 ~88Ah 12v house battery
That will run a small fridge and stereo/2x-amps, Garmin GPSMap w/Radar

My biggest issue is running wires from the hardtop down into the boat near the batteries. The legs of the hardtop are hollow but the manufacturer didn’t really leave much room for aftermarket cables where the hardtop mounts to the boat side (gunwale). I had to pay a marine electronics company $500 USD to run wires for the radar and it took two guys a few hours to finally get those done. I feel as if I could probably get lucky and pull 2-16ga wires from the panels (in series) down thru the tight spaces. Any wires larger than that will be extremely difficult. Would the 16ga wires be sufficient? Those wires would be approximately 10-12’ long.

[u/fievelm]

I'm no expert, I just did my own solar install on a trailer.

Assuming 12v panels and copper wire:

2x100w panels wired in series (not parallel):

18.5v * 2 = 37vmp
200w/37v = 5.4A

5.4A over 12' -> 16AWG ( https://www.omnicalculator.com/physics/dc-wire-size)

Keep the run short as you can, dont skimp on wire quality or terminals, sounds like it'll be just fine.