Pontoon Boat Solar Panel System

[sanfordturbo]

75HP 2-cycle engine, 2x12v batteries on a Perko switch (1,2,all,off), LED navigation lights (green,red,white), 3xLED house lights, and RADIO (max 7amp draw).

GOAL: I want to be able to run my radio for 8 hours without draining my batteries to the point where they won't crank the engine to start up. It may take 30-45 seconds of cranking to get that old sucker fired up. (not continuous cranking, but off and on while fiddling with the choke) The boat sits at my dock all day long during the week in direct sunlight, so the system should charge it up and trickle afterwards.

My brain is swimming after reading all day about solar panels, MPPT vs PWM, inefficiencies, formulas, blah blah.

I have completely confused myself and need some assistance to get my equipment ordered.

1. Want some kind of battery monitor so I know how much juice is left - (like a cell phone does)
2. I have a flat upper deck to mount the panel. 2x5 is not an issue. I plan on mounting this thing FLAT.
3. waterproof - did i mention this is for a boat?
4. max budget is $600
5. forgot what kind of batteries on the boat, but will gather that intel

Can someone help recommend products?

I am leaning towards something like this: http://www.solarpanelstore.com/solar...at.info.1.html

[bcroe]

Past RV apps have used 2 batteries with a splitter, one for cranking, and one you can safely run down. Bruce Roe

[ewarnerusa]

In an RV setup, I'd say go for 200 watts of solar minimum. I don't know boating, so I don't know how that impacts how much solar you'll need. 200 watts will keep those 2 batteries bursting full during storage, but may fall behind if you're cranking the stereo for 8 hours straight in poor sunlight. But I doubt the stereo pulls 7 amps full time when on, probably just that much potential peak amps with volume cranked.

At this small of a setup, I wouldn't worry about the more expensive MPPT controllers. Of course MPPT won't hurt anything and no one complains about having maximum amperage potential when it's needed.

True battery monitoring systems cost a lot, the RV world loves the Bogart Engineering Trimetric 2030 which runs $200+. This requires installing a shunt on the negative battery terminal and it monitors all incoming and outgoing current as well as logging amp hours. http://www.bogartengineering.com/products/trimetrics/
I recommend just getting a cheap volt meter and having an idea of the battery SOC based on voltage.

I've never heard of a solar panel that wasn't water proof, they are designed and intended to be used outdoors. You'll want your charge controller to be installed away from the elements though.

The kit you posted to is over priced, although they do look like nice components. I like Solar Blvd for 12V panels. https://www.solarblvd.com/index.php?cPath=1_272