• DogWater@lemmy.world
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      8 months ago

      No it doesn’t. Watts do give a shit what percentage is voltage vs amps. You have to convert between AC and DC as appropriate as well as ensuring the voltage of a 12v battery is stepped if needed, but the watts are the same in any case. (Not figuring for system losses)

    • JohnEdwa@sopuli.xyz
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      8 months ago

      Watt hours are watt hours. Sure the compressor won’t run on 12 volts as is but the energy is there, just needs a converter.

      Fwiw, our 15 year old fridge uses around 1000Wh per day.

      • genie@lemmy.world
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        8 months ago

        Sure, buy an inverter and burn up 10% of your energy in the conversion if you’re lucky. That inverter will cost roughly as much as the contents of a standard fridge + freezer, by the way :)

        At that point just buy a well insulated cooler and always have some ice on hand. It’ll last much longer.

        • JohnEdwa@sopuli.xyz
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          8 months ago

          The question wasn’t “Is it efficient or cheap”, it was how much energy is in a battery, and if and for how long would it run a fridge. If you also want to add one more point to why you probably shouldn’t do it, car starter batteries don’t generally like to be deeply discharged, you’d want to get a marine battery for that use.
          As for how much the inverter would cost, depends on the fridge, but Amazon has a 1000W inverter for around $85, that should be enough for most. Ours could run from a 300W one, they cost around $30. Pretty handy devices if you want to run any kinds of electronics from a car anyway, I have one for when I want to charge my laptop and RC batteries on the field.