Minimalist approach - OEM battery + solar?

[whitenoise]

Hey guys,

After some extensive searching, I feel like I could still do with some advice.

I have an LX470 aka 100 series Land Cruiser. It currently has the OEM Lexus battery with about 4 years left on the warranty, but I dont know its maintenance history. My power needs are middle-of-the-road - I have an Edgestar 80qt in fridge mode, recharging cellphone, tablet batteries etc. and around 50w worth of camp lighting for 2-3 hours a night. 2 days of power without starting the engine is what I'm looking for ideally.

I have a 5 day offroad/backcountry trip coming up in the Northeast next week and thinking about the simplest and most cost effective way to meet my needs. My options are:

1) Replace OEM with a Group 31 single (I can still use the OEM later on when I have time to make a dual battery setup)
2) Retain OEM and supplement with a Renogy 100w solar suitcase setup - about $275

Both are about the same cost-wise, and both add the same amount of weight (+30 lbs). The solar is a little more uncertain and weather-dependent. Is anyone actually using Option2 type setup?

 

[Yarjammer]

I'm running option 2 with my JKU and it has worked great so far this season, albeit with less loading. 50watts of lighting is quite a bit. I have LED light strips on my awning and under my RTT as well as on the rear of my rack. The LEDs consume 1.5watts per foot at full brightness and I usually keep mine at 25-50% since I'm not performing surgery. With all of my camp lighting on at 50% I'm drawing ~1.25amp/hr. My ARB 37qt is usually the one drawing the most power @ ~3amp/hr. During the day my 90watt solar setup can completely recharge my battery from the prior night while keeping my fridge running all day.

I'll be interested in seeing how my setup performs in the winter months where our nights are much longer than our cloudy days. My line of thinking is that I'll be okay since the fridge will have a significantly lower temperature delta to overcome.

 

[whitenoise]

Thanks for the reply. The 50w was really just based off of 2x27w work lights that I was planning to get. Agreed that it's a lot of lighting, maybe I should just get some rope lighting for constant on and just use the work lights when necessary.

 

[Haf-E]

The challenge of Option 2 is usually that you are driving during the daytime when the best charging occurs.

I've used option 1 on several vehicles with good results. The frig is the biggest consumer but, assuming you are driving for a significant part of the day - particularly when its hot out - you can possibly just run it when the vehicle is on and leave it off the rest of the time. This depends on the frig and what you put in it - but I often turn off my frig at night when I am sleeping to keep it quieter. Sucks when I forget to turn it back on though... should work up a special switch system that would power it if the engine is running even if I had turned it off...

 

[whitenoise]

But if you're driving during the day, you arrive with a full battery and should only need enough capacity until the next morning when solar kicks in, no?

 

[AndrewP]

Option #1 Could work. The reason is that a standard starting battery isn't really set up to discharge more than a few percent to get your truck started. Doing a fairly deep cycle will shorten it's life. Replacing the OEM with a battery capable of starting and some deeper cycle discharge.

I would also supplement that with the Renogy suitcase which works extremely well, and realistically can provide 35-50 amp-hours back into your battery. That way it stays topped up, and the panel will provide much of the real-time power to run the fridge. I have never thought turning a fridge off at night was a good idea. It kind of defeats the purpose, and you may forget to turn it back on and who wants warm beer?




You really should measure your loads, especially that big refrigerator. An inexpensive watt meter would tell you the power consumption pretty quickly and aid in planning your system. In the end you'll be most happy with a dual battery system, but that can take a while to install.

 

[228B]

If one battery in your expedition vehicle, then a Group 31 but preferably an Odyssey or SearsDieHard Platinum (Odyssey), because it's unique design and quality construction (99.99% pure virgin lead plates) contribute to it's ability to both deep cycle and start engines.

Add a solar panel and a charge controller, and you're in bidniss. You can have several charge sources connected at all times but it's better when only one is in operation, a setup you obviously can take advantage of in your situation. Driving = engine alternator charging. Parked = solar charging. Simple!

Component brands are up to you but why not "go big" as small systems go and use a 100-watt 36-cell panel and a nice little PWM controller. Be sure to use at least 12 ga stranded from panel to controller and preferably a minimum 10 ga stranded from controller to battery, with the controller as close as possible to the battery. If over 6 ft away, consider using #8 AWG stranded from the controller to the battery (but 10 AWG will do, but you'll have less system efficiency).

This opinion of mine posted here is specific to your original post. If it were a small solar electric expedition vehicle power system, I'd recommend the larger wire sizes.

 

[whitenoise]

Thank you all for the advice so far. I'm refraining from going the whole hog just yet. One reason is that this is a group trip and there will always be someone to help out if I run the battery down. I cannot justify the cost of a group 31 AND solar for this trip alone, so I want to do as little as possible that will get me by, while still keeping it "future proof". Just trying to think aloud as to which option is better bang for the buck from that viewpoint.

 

[228B]

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Yea that sounds like the way to go. Have fun! and keep us abreast of your system progress!
.

 

[AndrewP]

Thank you all for the advice so far. I'm refraining from going the whole hog just yet. One reason is that this is a group trip and there will always be someone to help out if I run the battery down. I cannot justify the cost of a group 31 AND solar for this trip alone, so I want to do as little as possible that will get me by, while still keeping it "future proof". Just trying to think aloud as to which option is better bang for the buck from that viewpoint.

In that case, I'd get the solar for your trip. It alone will mostly run your fridge and keep your main battery topped up. Plus, it's something you'll be wanting long term too and you won't be wasting any $$.

 

[Yarjammer]

Thanks for the reply. The 50w was really just based off of 2x27w work lights that I was planning to get. Agreed that it's a lot of lighting, maybe I should just get some rope lighting for constant on and just use the work lights when necessary.

That is how mine is setup. My two rear rack-mounted LED floods are primarily used for extremely dusty conditions on the trail, miscellaneous trail use, and very limited use while actually in camp. The strip lights are camp only. they are cheap enough on Amazon to give them a shot. I prefer the warm white which looks more like incandescent lighting.

 

[whitenoise]

That is how mine is setup. My two rear rack-mounted LED floods are primarily used for extremely dusty conditions on the trail, miscellaneous trail use, and very limited use while actually in camp. The strip lights are camp only. they are cheap enough on Amazon to give them a shot. I prefer the warm white which looks more like incandescent lighting.

Do you have a link to the ones you bought. Amazon is flooded with so many different varieties, its hard to narrow it down.

In that case, I'd get the solar for your trip. It alone will mostly run your fridge and keep your main battery topped up. Plus, it's something you'll be wanting long term too and you won't be wasting any $$.

Yup, I think that is what I'm going with for now. Is the renogy suitcase the only one to consider, or are there other alternatives I missed during my search? I dont want to mount to the roof but rather have it be a compact and easily portable package I can reposition away from the vehicle.

 

[AndrewP]

I've seen a couple of other folding panels on Ebay all around the same price. The Renogy unit is a good performer. I got it without the charge controller and used a CC from Morningstar.

 

[4x4junkie]

Do you have a link to the ones you bought. Amazon is flooded with so many different varieties, its hard to narrow it down.
.

I use these.
http://www.amazon.com/SUPERNIGHT-TM-Cuttable-Waterproof-Decorative/dp/B00F5N3U8Q

Very bright, yet soft white light (not the common cold clammy bluish-white LED color). There are dimmers available for them too, though I just use a little DC-DC buck converter I already had on hand to dim them.

 

[Ray_G]

I'd suggest #2 plus just a little insurance in the form of a microstart jumper...I have been very impressed by my XP10, having left it unattended in my truck for 2 months (in Abu Dhabi heat) and the other night at the airport a couple across from me came out to their van having left the lights on-not wanting to pull the jumper cables I decided to give it a shot and it started effortlessly.

On my LR3 I'm thinking of going along your option 2 route but already have the XP-10 as insurance.
http://www.amazon.com/Antigravity-B...TF8&qid=1438172053&sr=8-1&keywords=microstart