Practicality of using 12V Fridge when Boondocking

[WVrich]

Ok, I am being a little lazy here... I could do all of the research and calculations but I figured that this is what the forum is all about! - I have the 2020 Forester 3011 which has a 12V only refrigerator. I would like to boondock at a NP for a few days. I am wondering if anyone here has done similar - I can run the generator during certain daytime hours to recharge. I also have an extra 100 watts of solar re-charge to slightly help. It sure would be nice to have the fridge. I guess the other alternative is to pull the fuse on the fridge and just use a cooler for a few days. I wonder why they chose a 12V fridge versus a gas/electric model?

[Windjammin]

Last year we stayed in Denali NP for 7 days with no hookups. I ran my 2000 watt generator for 4 hours every afternoon to keep the battery recharged with no problems.

[WVrich]

Thanks! Can you confirm if you were using a 12V compressor type refrigerator?

[Windjammin]

Mine is 120 volt if power is available otherwise it resorts to propane and running the electronics off 12 volt.

[WVrich]

Thanks Again... My dilemma comes with the 12V powered refrigerator/compressor. I am not sure about the load from that beast.

[Reverse_snowbird]

I think you may have to resort to that cooler. Those are residential refrigerators and draw a lot of power. People really like the large residential refrigerators, but they don't boondock well.

[GravelRider]

WVrich is talking about a 12 volt only refrigerator. This isn't a residential fridge or a three way fridge.

I don't know which exact fridge you have, but I have a power-hungry Furrion 10 C.F. 12 volt fridge. I initially bought my trailer with an extra "upgraded" battery from the dealer and the 50 watt solar panel. Turns out it was actually a pair of cheap 75 Ah batteries. We mostly boondock, and that just wasn't cuttting it. Overnight, we'd always be below 50% battery life, and then spent hours running the generator in the morning to get some more battery life back and again at the end of the day to top off before the fridge sucked it down overnight. I swapped those batteries out for dual 6 volt GC batteries for a 215 Ah battery bank, and this made things workable. I still needed to run the generator daily, but doable. I was tired of always being reliant on the generator, so I upgraded my solar from 50 watts to 800 watts. I also bought another set of two 6 volt GC batteries. I haven't yet installed the batteries, but the solar alone is more than enough to keep up with the fridge.

So short answer, depends on your battery bank.

[TitanMike]

The consensus seems to be that if you have a 12 volt only refrigerator or even a residential refrigerator using an inverter three things are needed:

Plenty of Solar Power generation capability;

Larger battery bank;

Generator.

First thing I'd consider is upgrading batteries to "Lithium". More storage in same footprint possible due to ability to use ALL of the battery's capacity. Less weight so load is reduced or one can double the battery bank size for the same weight as lead acid battery bank they replace. Faster charging times on Lithium so smaller solar output is more effective than when trying to charge Lead Acid batteries. Ditto for charging with generator when run times are limited.

Camping in forests presents a solar power challenge due to shade. Only way to overcome is make solar array on the roof as large as possible, covering as much space as practical. OR Use a portable system that can be set up in the sunlight and moved as it becomes shaded due to sun movement.

Restricted generator run times can be problematic when using Lead Acid Batteries. By their very nature they can take 10 hours or more to FULLY charge, depending of course on charge rate and total capacity of battery bank. With Lead Acid batteries you are only charging the first 80-90% in the first 4-6 hours and then the remaining 10-20% can take the same amount of time to complete the "electro-chemical" reaction inside the battery. Lithium on the other hand is close to 100% efficient when charging. If batteries are down 100 amp hours, and you charge them at a 50 amp rate, two hours later the batteries are "full". Makes it very easy to fully charge batteries within the limited generator hours if that's all one has for charging.

Just something to consider to make life much easier with a 12 Volt refrigerator if you do a lot of dry camping/boondocking.

I made the change a couple years ago and I don't even have a 12 volt only refrigerator. Not having to worry about running out of power on a cold night, worrying about restricted generator hours or not enough sun, all make for a really relaxed time in the boondocks, NF Campground, etc.

[njfishing]

Great article on how long different fridges will run https://rv52.com/how-long-will-rv-fr...un-on-battery/

If DC only no very long - A standard RV fridge, while running on propane draws a negligible amount of current to power the electronic control panel up front- so if that’s the only power draw, your batteries could last weeks. Running it on DC electricity, though, will drain your batteries in about 3 hours. That being said, home refrigerators (compressor type) are more efficient on electric but will still exhaust your batteries in about 12 hours.

[tomkatb]

Math is real simple.

You need enough batteries and a way to recharge.

You have to have the batteries. Likely 200 amps total. (I would want 400). Plus 100 watts of solar, and the generator every day for 4 hours. A standard dealer installed battery two years old will power the fridge for a few hours 4-5.

This is to only power the fridge. Add a cpap and moms coffee pot and maybe not.

[bikendan]

Originally Posted by Windjammin

Mine is 120 volt if power is available otherwise it resorts to propane and running the electronics off 12 volt.

The OP is asking about the performance of a 12v ONLY fridge, not about a 2-way fridge.

OP, the line on why they're installing 12v only fridges is cost. The 12v fridges are cheaper than the 2-way RV fridges. They are bigger also.

[Kenludwig]

I have the 12v ref really sorry I got it my unit is a 2019 just got back from a week away stayed 1 night Boone docking the best I found so far is having 2 series 29 batteries which are about 105 ah each. A 100 watt solar panel. And a 2500 generator. Problem is u are not running ref only u have your water pump and lights smoke and carbon detectors everything draws some of the 12v using both batteries at night solar panel during the day and generator a FEW hours a day u MIGHT make it...if we drive anywhere during the day I take one battery in the bed of my truck and hook it up to a connection I put in that will charge it while driving. ALL THIS COULD HAVE BEEN MUCH EASIER IF THEY WOULD HAVE JUST PUT A 2 WAY (110volt/gas) Refrigerator in... Last camper I buy with a 12v refrigerator....

[tomkatb]

To use a compressor fridge and boondock would take 200 amps of usable storage. 4 gc2 batteries or 2 Lithium 100's and 600 watts (150 amps) of solar. Plus a generator of some sort and lots of sun. Western states.

Yes fairly practical.

[Bob2019]

Originally Posted by bikendan

The OP is asking about the performance of a 12v ONLY fridge, not about a 2-way fridge.

OP, the line on why they're installing 12v only fridges is cost. The 12v fridges are cheaper than the 2-way RV fridges. They are bigger also.

Yet RV cost keeps going up several thousand a year and unless you don't travel far, have electric hookups every day, have lots of sunshine for solar, more batteries that add cost and weight, running a generator with polution and noise for 4 hours a day, more valuable RV space taken up with a larger refrigerator, this is what we are expected to put up with a 12 v refrigerator that will run on batteries for 4-5 hours a day. Sure they are bigger, but probably require more energy to cool more food. This is camping or RVing. You don't really need a huge refrigerator.

[jimmarako]

OK, this is not my thing. But I thought I'd pass along some info. On the Rockwood Mini Lite facebook page one of the Mods runs a blog (stressless camping). The had an interview with Josh the RV nerd. They talked about fridges and 12V was the future (even though they have been around for ever) and better than residential fridges. And even for boondockers they shouldn't be a problem.

Here is a video from Josh about test data from Furion. I'm sure the experts here will have a field day with it. But they claim running the fridge should not be a problem. A single 75 AH battery will give you 32 hours of time.

https://www.youtube.com/watch?v=HNCn...-3hhCBKenCnmSg

I'll see if I can find the blog posting as well.

Again I have no knowledge either way, just passing along info.

Jim M.

[larry2c]

I guess I don't get out much - never seen a 12V only fridge. Is it a compressor type fridge or absorption using a 12V heating element?

[jimmarako]

I think this is the podcast I was looking for. I can't view it at work. :-(

https://www.stresslesscamping.com/po...5aBg5bgKxdZ_RA

Jim M.

[tomkatb]

Deceptive data from the refrigerator manufacturer. People report seeing draws of 10 or more amps per hour.

No trailer matches the test condition.

Most fridges are not installed in rv’s following the installation instructions. An air space surrounding the units is required. Acts like a heat pump in a trailer.

You cannot run batteries over 50%

Josh also did a spot on never ordering another rv with a residential fridge!

Most folks who have them say two 100 amp wet cell batteries will not make it thru the night. Remember an rv has other loads.

The math says they could under un normal operating conditions.

Campers report that typically solar cells on their roofs produce at. 35% their rated output.

When we arrived in Texas the rv was over 110 degrees. They are temperature dependent.

Nothing wrong with them, but the are battery hogs. Batteries are the weak link!

[WVrich]

Sounds like there are a lot of different opinions and observations on this subject.

I think my best path forward is to simply try it and see! I will keep an eye on the batteries SOC >50%.

I will note the ambient temp and I will pre-cool the fridge while powered-up.

I think I will run this test in the evening as to isolate the fridge and just a few lights. I can always add back the 100w solar charging affect.

I am doubtful that we can expect this fridge to be able to run for even one night without the need for a generator re-charge in the AM.

[rsdata]

12VDC only fridges for a boondocking camper sounds like a step backward from the 12V/propane type... are they that much cheaper to make?