Solar charging for camping.

[Cactus Red]

Our initial solar charging system for a single ARB 47L fridge/freezer was a Goal Zero Escape 30W Solar Panel Briefcase unit and Guardian 12V Charge Controller. It did OK, but voltage still dropped to where after a full day in hot weather, we needed to augment it with starting the truck for about 30 minutes before dark. So we added a second Boulder 30W Solar Panel for a combined 60W peak charge. This worked great for multi-day stays without starting the truck.

We're now using two ARB's for food and beverages. Both are powered via the trucks electrical system that consists of a G31 DiaHard Platinum and a G65 DieHard Platinum battery. That should provide roughly 100 A/H before the batteries drop to 50%. Previously the G31 has been isolated from the starting battery, but with the two ARBs, I'm leaving the two combined. In cool weather, the two panels did OK, but still lagged at the end of the day. Recently we spent three days in moderately hot weather (86 to 90 degs) in zero shade. The fridges ran pretty much continuously, and 60W was no where near enough to maintain a charge. After 13 hour days in the heat, voltage was down to 12.06. To bring it back to 12.6, I had to run the truck for nearly 40 minutes.

So it's time to upgrade. After looking online for info, and doing some easy calculations, I selected a new 100W setup from Renogy.

http://www.amazon.com/gp/product/B00HR8 ... UTF8&psc=1
http://www.amazon.com/RENOGY%C2%AE-20ft ... B00B96HSHC

This should be easier to use, has a better charge controller, and with the addition of a 20" extension, allow us to remain in the shade if there is any, while the panels are in the sun.

Mark

[azracer]

I get most of my solar panels from these folks. https://www.solarblvd.com/ They have been great to deal with for my orders. I have purchased a little over 8000 watts of 24v panels from them when they had panels by the pallet sales. I got mine at 0.52 cents per watt delivered to a commercial address!

This link has similar to what you are linking to but with more watts and at a lower cost. 6.17A on Amazon vs 7.3A for this one

https://www.solarblvd.com/product_info. ... ts_id=2756




.

[Cactus Red]

That's a nice unit KP!

I am constrained by size to have fit into the camper for storage, and the Renogy will with ease. The one above is too wide - all the panels above 50W are.

The Renogy also has a charge controller and 15' wiring w/ battery clips included.

[Takingatrip1]

I've got the same renogy set up. Great quality, used it to charge my trailer battery

[azracer]

When I had a pop-up (1984 Starcraft Starflyer 19') I put my 4 120 watt panels on the front bed mattress facing down and put our heavy quilted winter blanket on them for folded camper transport. My 30 amp charge controller was on the inside where the camper battery was as the voltage drop is minimal between the panels and the controller (@20+ volts) but is very critical between the controller and the battery where it is regulated down to 13.8>14.2 volts. I had 30' of cable to the controller from the panels and about a foot or two to the camper battery. I left the truck hooked up to charge throught the trailer plug to both truck batteries through my isolator/controller. I quite literally had no issues with daytime power use and started every night with fully charged set of batteries. I designed it with cloudy days in mind.

As you know I have an electrical background and designed and built my entire off grid system myself and yes I had to get my plans approved by the county.

[Cactus Red]

Yup, I know you've got the knowledge and the experience KP. Glad to have you share it with us!

[azracer]

Was only trying to justify/clairify the fact that I have experience in these systems. Was not bragging LOL.

I can't fix your space constraint problem but can help design a system to give great bang for the buck. I bet 6.17 amps will likely do the job on hot sunny days but it will be close for sure when clouds show up on a 90 degree or hotter day.

As for your propane fridge in the RV I used a 6" and a 3" 5V PC cooling fan that I powered with a dual USB to 12V cigarette lighter power adapter. I put the 6" fan in the heat exchanger outside compartment in the top exhaust vent to assist with exhausting the heat. The 3" one I mounted inside the back corner of the fridge on the side and up near the cooling coils. I mounted it with spacers behind it to help move the air around inside the fridge. Made it work as good as the home refrigerator! I just unplugged the dual USB adapter at night to conserve battery power is all. Those fans made it go from a useless fridge to an awesome freezer/refrigerator appliance.

[Mule]

Are you dead-set on a solar option, or are you willing to consider a generator/charger?

My sled trailer has a 25k BTU propane-fired furnace with a 12v blower (~7A) and 12v lighting. From a full charge, I can easily go overnight, even through a weekend if it's not super-cold out.
Then there's all the stuff I use through the day that usually needs recharging - Phone, camera(s)/gear, flashlight, GPS, radio(s), laptop, etc.
I have a 2kW Generac suitcase gen that'll run for about 3 hours on a tank (1gal) of fuel. With the 20A charger pumping current into the trailer batt (or trailer+truck if I flip the disconnect switch), it'll put a pretty good charge into the trailer and hardly even break a sweat, along with charging everything else I have. If I need light (like from a 600W halogen) to work on a broken sled, I have the ability to do that.

Solar's great and all, but ... I think it gets more credit than it should. You need a *LOT* of surface area to actually do stuff with it. For maintaining RV batteries while it's in storage, solar is a perfect solution.
Pretty easy for me to fire up the gen for a couple hours while I'm getting the sled ready for the next day, changing out of riding gear, cookin dinner, and processing photos from the day.... shut the thing off later in the evening. A good Honda or Yamaha 2kW unit will set you back about $1k... and you get electricity whenever you want, regardless of time-of-day or cloud cover.

Trailer in snowmo-camp-mode


Generac ix2000


Gen chained in the bed, extension cord from gen to trailer.

[Cactus Red]

Don't short yourself KP. You've got way more time and effort into solar than most of us ever will.

The three way in our camper is used for storage. I'm looking at removing it completely to add some more space for stuff. It's small too - the ARB's have more capacity.

A generator is 100% out. We camp in remote locations to get away from the RV crowds in the summer. Most of our favorite spots require 4x4 to get to - that's why we use the StarCraft 10RT trailer, it will go almost anywhere the truck will, yet gives us a 21' camper when we get there.

Dennis Miller "You can't order black coffee anymore. It's un-creamed..."

[BigRed2007]

I run 2x 50W panels to power my Whynter fridge, CB and HAM radios. I use a Morning Star Sun Saver Duo to charge the house battery and trickle charge the starting battery (both optima yellow tops). The batteries are on a TMAX battery management system and generally isolated. I have never had a problem with the house battery not keeping up over night (fridge has been running for months). Running more than a couple 100W from the inverter requires the batteries be linked and the truck be started.

The only issue I have had is with mounting the panels to the truck while making it look good and be secure. I want the panels mouted to the truck most of the time, we are tent campers, so I used magnets for 18 months before and 80MPH cross wind removed the panels for me (I wasn't even running the fridge, I should have removed the panels). Now they are bolted to my unitsrut rack and it doesn't look the greatest but works awesome.