Solar powered adventure trailer

[DeMented Toys]

I've built my own "adventure trailer." It's been quite a project so far. I'm finally wiring up and trying to figure out my solar power, battery bank, and charging stuff. Here is a link to my build that also includes my solar power dreams.

http://www.expeditionportal.com/forum/showthread.php?t=59967

 

[DeMented Toys]

I've got a 60 watt panel, 8 sealed gel batteries and 2 marine batteries. So far I have wired the batteries together in parallel with 4" pieces of 4AWG wire. Right now I have a battery tender hooked up and plugged in and I have also hooked up my solar charge controller and my panel just to test it out.

 

[DeMented Toys]

The 2 marine batteries will go in a tongue box that will also house my solar charge controller, fuse box, battery charger to connect to shore power when available, and whatever else I need.

I want to run interior LED lights, an exterior LED flood light, charge my laptop and cell phone, power a HAM radio, an occasional coffee pot in the morning and maybe a fan.

Now, I just have to figure out how to wire it all in the best way, where to put which type of fuses, and such.

 

[DeMented Toys]

I have been googling and reading, and googling and reading more. It seems simple but there are so many options for solar controllers and hardware, then there are Amp hours, watts, Volts, DC, AC...... Holy crap. The more I learn the more complicated it seems. If anyone can break it down into plain English I'd really appreciate it.

I have the batteries wired in parallel. And if I'm reading right the red sealed batteries are 38 amp hours each? Is that right?

The 2 bigger 12v marine batteries don't have amp hour ratings on them.

 

[DeMented Toys]

My solar charge controller is a SunShield with an input rated at 12 Volt 8 Amp. This should work with the 60 watt panel, right?

 

[4RunAmok]

You are drawing power from your batteries incorrectly as pictured above.

In the bank, you should draw positive from one end of the bank, and and negative from the other end. Charging should be applied in the same manner.

This will ensure that all batteries drain and charge equally. As opposed to a really discharged one at the draw end and a fully charged battery at the opposite end. (I hope that makes sense)

 

[4RunAmok]

My solar charge controller is a SunShield with an input rated at 12 Volt 8 Amp. This should work with the 60 watt panel, right?

60 watt panel divided by 12 volts = 5 amps. So yes, an 8 amp controller is plenty. You have very little upgrade room left if you add or change panels, though.

 

[4RunAmok]

It's not shown in your photos, and not clearly stated in your descriptions, but I would not recommend pairing these 8 gel batteries with your two marine batteries. I know you did not list their specs, but I'm guessing the two marine batteries are much larger in size, and likely amp hours, cold cranking amps, etc..

You will want to use a charge controller that can handle multiple banks of batteries, two separate solar systems, or charge the tongue batteries with the vehicle's alternator by way of the trailer plug (or better yet, add a new plug at the bumper) while you're driving.

A single bank charge controller working on a single bank of dissimilar batteries will not charge any of them correctly. Enersys/Odyssey batteries are VERY particular when it comes to charging.

 

[DeMented Toys]

Thanks. I haven't hooked the two marine batteries up yet. I could just use them as backup and charge them from my alternator, like you suggested.

Thanks for the charging info too. So I need to hook to a positive on one end and a negative on the other end of the parallel 8 battery bank, right?

 

[loren85022]

Just curious, could you describe what you do and where that requires this amount of total battery volume?

 

[Jeff Wanamog]

Yes, I am curious too! That is an absolute ******t load of storage capacity. I have 200 AH in my trailer and even with all the components I run, parked in the shade for three days, I have never came close to using what I have.
One suggestion though, if you are going to use all of those batteries to run something that has a large amp draw, like maybe an inverter, you may have used too small of cables.

Jeff

 

[madmax718]

Curious as well.

with a 60w panel, thats a lot of reserve power. You'd be lucky to recover more than 3 amps per hour. The only times I've heard about people sizing batteries this way is if they have a very high initial draw, but then long periods of no draw- like a sump pump during a rain storm, remote radio transmitters due to power outtages.Other times I've seen much smaller batteries but a lot of them for short duration/high current operations-

This setup is like the best of both worlds, but its a heavy package.

 

[DeMented Toys]

Well, I got a good deal on the 8 batteries so I figured I may as well use them. . And my buddy gave me two new marine batteries ( series 24) that he had in a camper that he sold. I got the 60 watt panel for cheap too, otherwise I probably would have just charged them off my truck and via shore power.

I'm only going to be powering LED lighting, HF radio, my laptop and cell phone, a fan for cooling at night, and a coffee pot in the AM.

I have two propane tanks on the front for cooking....

Should I leave off the two marine batteries? I'm new to this whole solar/battery powered adventuring, so I'm here to learn.

 

[DeMented Toys]

Here is my marine battery setup. I just put them in the tongue box tonight. They are heavy and if they are overkill in addition with the 8 other 38 Ah batteries maybe I can find another use for them.

 

[loren85022]

The good thing is you can yank batteries until you get it right for your travels. For us, weight matters too. It's been known for us to trek down a dead end. And having to unhook and reposition made me realize, keeping things lean is part of the equation. Based on your description, I'd bet 2 healthy batteries and a few means of recharging will work fine.