What do I need to mount on my truck camper?

[jacampb]

I plan to live out of the back of my truck travelling around for a year and I was wanting to hook up a second 12V battery. I've got a marine battery my grandpa gave me, was going to just hook it up to my other battery with an isolator and let the alternator charge it but my brother is telling me he'll buy me a solar panel if I want (a sub $100 amazon panel).

My options seem to be a 15W Amorphous panel by SunForce or a
20W Monocrystalline panel by Instapark or HQRP

My question is really this:

If this is going to be flat mounted to the top of my camper shell should I be getting amorphous or mono crystalline? I've read that amorphous does better in cloudy weather and indirect sunlight, whereas monocrystalline is so much more efficient.

As far as I'm able to discern, pro of the amorphous seem to be:
Better with indirect sun (how much better we talking here?) and clouds, since it'll be flat mounted, indirect the sun will be.
Con of the amorphous is that for the 15W it's 38"x13" and weighs a lot limiting my options for expanding.

Pros and cons of the mono are opposite.

Am I going to be able to significantly charge a 12V battery with 15W panel flat mounted if I'm just running little things off of it like LED overhead lights and charging my laptop and cell phone and maybe a little electric stove daily? If 15W will be enough, maybe I shouldn't worry about expansion and just get the amorphous. The monocrystaline is 1/3 the size though...

Thanks so much for your help. Also if you think I should just go the alternator route... don't be shy.

[Naptown]

Neither will do much for you on a daily basis. If you are moving around the alternator will be more than sufficient

[Mike90250]

For a $100 panel, unless it's over 100w. I'd not bother drilling holes in a sound roof, to mount it. It won't do much to stretch your power budget, and the holes may leak.

Sounds odd from a Solar Guru, but some things are not worth messing with. A relay type isolator, and you shoud be OK. Maybe a small 1,000 w inverter style, auto throttle genset & a beefy battery charger to run off it, is what I'd look at first, instead of cranking up the vehicle engine for recharge.

[jacampb]

I will be moving around but probably not more than a couple times a week, certainly not daily or even every other. That's all the worried me about the alternator idea. (i'm not sure how quickly my alternator would bring both batteries back to full charge).

If I stretch my budget to 120 (you're supposed to be the ones convincing me to stretch my budget! ) I could get a 30W but that's it. So 15-30W wouldn't keep a battery charged that's just got lights and battery chargers going off of it?

[jacampb]

another question. Do i really need a controller when we're talking about such a small panel? Is there really a danger of overcharging?

[Naptown]

I will be moving around but probably not more than a couple times a week, certainly not daily or even every other. That's all the worried me about the alternator idea. (i'm not sure how quickly my alternator would bring both batteries back to full charge).

If I stretch my budget to 120 (you're supposed to be the ones convincing me to stretch my budget! ) I could get a 30W but that's it. So 15-30W wouldn't keep a battery charged that's just got lights and battery chargers going off of it?

you need to do an energy survey of sorts. Determine what your loads are daily for lights charging etc. in watt hours Then figure that that 30 watt panel will produce maybe 30-60 watt hours a day. I think you will find yourself coming up way short.
What I would suggest is installing 2 house batteries on a three battery isolator and either run the camper for an hour or two a day or when you move. That much solar won't do much

[Naptown]

another question. Do i really need a controller when we're talking about such a small panel? Is there really a danger of overcharging?

Probably not if it is rated as a 12V Panel

[jacampb]

just to clarify and because I don't know if this will make a difference in alternator charging, but I'm in a 4cyl ford ranger with a cheap aluminum camper shell, not a camper. Will I be able to charge both batteries on relatively short drives?

Mounting a solar panel to the shell doesn't really worry me, since the shell is worth like 50 bucks. Maybe I'll just hook the battery to the alternator after all... shucks.

Another question, when charging a battery I read they give off hydrogen gas. Only place I've got for it is in the bed of the truck next to the bed of me. How does one remedy this?

Ok - back to original question - am I gonna be looking at comparable losses between amorphous and mono panels by mounting them flat or will the mono suffer more? Also without having to get a controller I could possibly swing a 50W.

Supposing I swung a 50W (or a 30W with a controller), I should expect to actually get 30w-60w charge per day with the way I'm mounting?

[Naptown]

how it is mounted, the season you are in and how you park are going to be the biggest factors. Flat on the roof in the south will work great in the summer. Same scenario up north during late fall early spring not so much. Winter forget about it anywhere north of Florida.

Read some of the threads in off grid living and you will get an idea of what you are getting into.

[Naptown]

just to clarify and because I don't know if this will make a difference in alternator charging, but I'm in a 4cyl ford ranger with a cheap aluminum camper shell, not a camper. Will I be able to charge both batteries on relatively short drives?

Depends on the alternator output and RPM of the engine during the drive but I would say a half hour would do it

Mounting a solar panel to the shell doesn't really worry me, since the shell is worth like 50 bucks. Maybe I'll just hook the battery to the alternator after all... shucks.

Good idea

Another question, when charging a battery I read they give off hydrogen gas. Only place I've got for it is in the bed of the truck next to the bed of me. How does one remedy this?

There are caps that will recombine some of the outgassing but I wouldn't smoke there while driving ( Impossible to do by yourself)



Ok - back to original question - am I gonna be looking at comparable losses between amorphous and mono panels by mounting them flat or will the mono suffer more? Also without having to get a controller I could possibly swing a 50W.

Depends on the voltage of the module and AH capacity of the Battery

Supposing I swung a 50W (or a 30W with a controller), I should expect to actually get 30w-60w charge per day with the way I'm mounting?

A little more but not much

Responses in red

[Sunking]

OK you need to be honest with yourself and ask yourself what will this really do for me?

Well with a 20 watt panel on the best of a summer days will generate about 60 watt hours of usable power to the battery, and that is stretching it a bit to make it sound good.

OK your Ford Ranger stock alternator is rated at 60 amps, and can generate 60 watt hours in 5 minutes. So armed with that info now answer the question: What will this really do for me?

Will the truth is it will cost you money and buy you nothing.