Is it more efficient to run a fridge freezer using 12v DC rather than the 120v AC? I imagine using the 120v AC on a portable battery requires inverter power. Is this a thing or no?
fridge freezer battery question
- Thread starter Tommy B
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perhaps I should be more specific. I have an ARB 63q fridge freezer. Would my battery last longer using the 12v DC or 110v AC plug?
The experts will weigh in soon, I hope, but it is much more efficient to use 12V DC. Running through an inverter to get to 110V AC and then reverse it for the fridge creates losses.
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In an ideal world it wouldn’t matter. In reality stick with 12v only. Going the other route you have conversion loss in your inverter and in the transformer for the fridge. It’s a lose lose.
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Much larger gains will be realized by keeping the fridge as full as possible and only putting warm items in if you are driving. Cold items and minimal empty space will keep run time to a minimum.
I unfortunately haven't tested this battery/ solar setup i have. Going on a 10-12 day trip. Waiting for the eco flow r600 that's still in production. Just had to pickup a cheap Rockpals 300 and solar panel. I need to use it all next week. I'm trying to find ways to keep this smaller battery maximized...it's just for powering the fridge. I can't bring myself to pay $140 for the insulating transit bag...seems way overpriced for what you get.
On a side note, Here is a fridge slide I made. I'm going to mock it up tomorrow to see how it works.
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Sweet. I didn’t realize they made a double slide like that. I used their slides in my teardrop galley.
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You lose energy in the conversion using a inverter to go to 110 AC, then back to 12VDC. Stay with 12VDC! Does you Fridge/freezer have a low voltage cut out, to save your vehicle battery? Use it and my guess you can go all night fine. But may have to start and run your vehicle each day and charge everything back up. Also, if you do use the inverter going AC, you will loose the low battery cut off built in to the Fridge/ Freezer, unless your inverter has that option built in also. Vance.
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I wrote the first sentence wrong. You loose in the conversions of energy from 12VDC. To 110 ACV. Sorr y for the confusion! Vance.
Here's the fridge slider i made
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Well done on the slide. I just installed the Smittybuilt 52 Qt fridge and it uses around .7ah which was much more efficient than my last one. I believe your ARB will be close to the same draw. I looked at many options including solar and and isolator to charge the second batter from the alternator, which is what I had in my last rig. I ended up with an AGM battery that seems to be lasting 18-27 hours before getting down to 12.2 volts. I have it set up to charge via a NOCO charger, through the truck's inverter while driving. I had to do the 400 watt anytime mod and I installed an outlet in the rear of the center console. I've had this on for 2 weeks now and it seems to work perfectly. For me, I wanted it to remain cold while the truck sits for at least 12-18 hours. I didn't want to run a DC-DC charger, (needed for the Toyota alternator), or install solar. It looks like this will work well and when I get home, it's easy to remove and set aside.
To answer your original question, and hopefully to help others with the same question: Running a 12v fridge on 120v (AC) will incur inverter losses of around 20% give or take the quality of the inverter.
It will most definitely be better to run on 12V (DC) rather than 120V (AC).
It will most definitely be better to run on 12V (DC) rather than 120V (AC).
