# Planning a small isolated refrigeration system



## koyote (12 mo ago)

Hi! new here- I'm just getting started on a fresh off grid build in NW Arizona.Not my first time off grid, but it's different every time!

I've got a septic in, which ate up a lot of the budget (but now the county doesn't care what I do) - I can get by pretty primitive on most things, but it's an hour to a paved road, probably 2-2.5 hours to grocery shopping. Two of us up here- mostly eating meat, so I need a freezer set up pretty much immediately.


I want to do this, for now, as a standalone isolated system- not intended to supply anything for lights or charging devices.

There is NO grid up here, so it's not a backup if the power goes off. The nearest pole line is something like 7 miles thataway. 

So I'm looking at the newer low power compressor 12 volt refrigeration units. The prices are all over the map, and the sizes are pretty limited. I can get something uselessly tiny for $179 or a commercial rated 90 quart 2 zone stainless unit for $1400- and everything in between

But a decent 5-7 cubic foot household AC chest freezer is gonna cost me $450. Plus inverter (which has to be beefed up for the AC compressor start, so it's going to probably be a 2500 or 3000 watt not harbor freight one) , plus apparently a larger battery bank. More consumption.

I can save some of that with timers- not running the fridge for 12 hours out of the day.

The new generation 12V (or 24v) larger (60 liter) units seem to draw 65 watts or less, 12V 5.5 amps max rating on some, 5 on others, etc. - no inverter, and about as simple a setup as you can get for an isolated solar install. (couple panels, 300-400ah battery bank, cheap charge controller, fuse.)

The problem is, again, you are looking at... mostly 2.1 cubic foot (60 liter) units.


that's gonna range from $350 to $500 for the unit. I am starting to think it would be cheaper to get two of those and see if I can store enough- I SHOULD be able to store 6 days meat per cubic foot. However, with anything less than 7 cubic feet i can't really take advantage of opportunistic sales or butcher shares.

Our current fridge until I get an initial deck laid out for the yurt (while I build something) is in a 1995 roadtrek- and it gets about a week and a half on the onboard propane, and is even smaller! (and I need to sell the roadtrek)

I don't want to spend $2000 on this right away - and I have 2x100 watt spare panels plus 400 watts of movable panels for the jackery 1500 system we have been using for camping.

In any event, I'll be adding an inch or more of rigid foam insulation to the outside. That's the easy hack.

Other considerations:

I can power the 12vot one (or two) directly off a vehicle or the main power (jackery) if I need to in an emergency. 

But- I'm not sure how trustworthy these units are.


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## paraquack (Mar 1, 2013)

For what it's worth! I purchased a Norcold AC/DC fridge capable of going down to zero degrees in 85 degree ambient temperature, back in 1972. It was a open box/return item at the local Montgomery Wards return center. Cost me $99. I don't use it very often any more, but it is waiting in the garage, sitting on the bench waiting to be pressed into service. I only use it as a backup and when I find a fantastic deal on meats. My recollection is 4 amps at 12/volts. Just for giggles, I pulled it out and connected it to my car. Fired right up. Are today's units as good? Who knows. Wish you luck.


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## Chiefster23 (Feb 5, 2016)

You can install a ‘soft start’ system on the compressor that will reduce the starting spike amperage on starting.


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