Solar for my Jeep

[comptiger5000]

I'm looking at throwing a couple of panels on the roof of my 98 Grand Cherokee. The available space is about 34" by 54" to not interfere with the sunroof. I'm thinking of running 2 of these: http://www.amazon.com/ALEKO®-80W-80...1436293125&sr=8-12&keywords=aleko+solar+panel

That would get me 160 watts and mostly fill that space. For the rest of the setup, I'm looking at the small 15 amp Morningstar MPPT charge controller. I've seen a few cheaper MPPT units, but none that support a remote battery temp sensor (battery is under the hood, controller would be either in the cargo area or under the back seats).

What are your thoughts on the setup and what parts could be chosen better?

 

[dwh]

Looks fine. PV module only has 3 feet of wire though, so you'll need some more and also a couple of Y connectors to parallel the panels.

 

[228B]

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(battery is under the hood, controller would be either in the cargo area or under the back seats).
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What are your thoughts on the setup...

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Ideally, the controller should be positioned as close to the battery as possible, to limit volt drop. You're not putting the controller under the hood for the obvious reason that it's a high-heat environment unsuitable for most solar charge controllers (which are designed primarily for static, non-mobile application). So...
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Please consider investing in some serious wire, in your case at least #4 AWG due to the length of the run. If you can place the charge controller far closer to the firewall, then #6 or #8 will be sufficient. Reason being that due to voltage drop from insufficient wire size, your battery may see sufficient current but insufficient voltage in order to become truly fully-charged. If you're depending on one battery only, this is a most important consideration.
Fortunately the battery remote temperature sensor you're thinking of pairing with the SS MPPT 15L comes with something like 30' of wire so you're good to go, there (and it's just #22 AWG and not an issue w/ volt drop because it carries no real current).
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[dwh]

/.Reason being that due to voltage drop from insufficient wire size, your battery may see sufficient current but insufficient voltage in order to become truly fully-charged.

That's a common misconception. Voltage drop when charging isn't much of an issue. It won't prevent the battery from reaching full charge, it just makes it take a bit longer.

Voltage drop is a function of load. As the battery state of charge rises, the amps flowing goes down. As the amp flow goes down, the voltage drop also goes down. By the time the battery approaches full charge, the voltage drop is pretty much gone because there are only a couple of amps flowing.

 

[comptiger5000]

I've already got a run of 2ga to under the back seat for the power inverter and a run of 4ga to my aux panel in the back. Having big enough wires to feed the 10 - 15 amps of solar charge current through isn't an issue.

The only reason the charge controller will end up back so far is that those are my 2 available spaces to put it without getting in the way and they're fairly close to where I'll likely end up bringing the solar wiring into the cabin.

And yes, the setup is just a single battery at this point. Even if I run a fridge in the thing, I won't need to run on battery power for more than about 12 - 14 hours before the sun comes back up to charge the battery or the Jeep gets driven. It shouldn't take dual batteries to do that and still have enough juice to start the motor. Worst case, if I weren't going to drive it for a day and it was cloudy and I were worried about having enough power, the AGM battery will soak up a ton of current and the Jeep has a 150 amp alternator, so I can bulk charge a good bit of current into it pretty quickly with the engine running at high idle (it burns just under 1 gallon per hour at high idle, so this isn't something to do frequently, but it's feasible to run it for an hour to charge up if I really needed to).

 

[4x4junkie]

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Please consider investing in some serious wire, in your case at least #4 AWG due to the length of the run. If you can place the charge controller far closer to the firewall, then #6 or #8 will be sufficient. Reason being that due to voltage drop from insufficient wire size, your battery may see sufficient current but insufficient voltage in order to become truly fully-charged. If you're depending on one battery only, this is a most important consideration.

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This is very sound advice. You want the best chance of the battery actually completing it's charge while the sun is still up in the sky. Anything that "makes it take a bit longer" will only cause your battery to die that much sooner. Having #2 wire on your setup, you should be good to go.

 

[228B]

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^ ^ ^ Indeed.
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comptiger5000
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Worst case, if I weren't going to drive it for a day and it was cloudy and I were worried about having enough power, the AGM battery will soak up a ton of current and the Jeep has a 150 amp alternator, so I can bulk charge a good bit of current into it pretty quickly with the engine running at high idle (it burns just under 1 gallon per hour at high idle, so this isn't something to do frequently, but it's feasible to run it for an hour to charge up if I really needed to).

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See! You've got it wired! lol.
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dwh
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By the time the battery approaches full charge, the voltage drop is pretty much gone because there are only a couple of amps flowing.

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As long as the battery sees to the tenth of a volt what the peak voltage that the controller intends to send during any absorption phase, better yet the voltage that the battery really wants according to it's manufacturer, he's good to go. For example, EnerSys/Odyssey/DieHard Platinum AGM batteries, according to Odyssey, anyway, should see 14.7 volts during absorption. i r xyctd cuz I've tuned up my Morningstar SunSaver MPPT 15L to do just that, and with a 13.6 float, just like the EnerSys' OMAX 50A 1B charger. Remember, I'm the no0b in town, here...

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[CaliMobber]

I almost have one of those panels on my car My 85w panelwith a morning star pwm charger. Its a great panel and I highly recommend it. In the sense of easy, I went against all my advise and I just put my controller in the back of the car next to my fridge 12v plug using the 6gauge wire running back to the batteries. I did this since it was the simplest and cleanest way to get my wires into my car and I had a good place to mount it.

For the wires, I just opened the back panel and removed the wires that came with it and put my own on since im not a fan of the aluminum wires they come with .


I was pretty resistant at first from reading handybob but DWH is fully right , it will still full charge, just in theory would take a little longer but I think in a cars situation its a non factor since when we drive, we are charging at 150amps (in your case) and with 160w you will be more than fine in any weather. My edgestar is set to 40deg and it lives in my car always. My car will sit for up to 10 days some times with solar keeping the system nice and healthy.