A mini car fridge 12v is the ultimate in camping comfort. Menus can be expanded to include pretty much anything you can cook at home, as long as you can fit it in the fridge. These days, portable fridges are extremely popular additions to any camping and 4WD arrangement, and if you head out regularly they become well and truly worth the expense.
However, a fridge requires a fair bit of energy to run – it’s almost always the highest consumer and you need to get that power from somewhere. There’s a lot of focus on solar panels and batteries, but there are a number of things you can do to reduce the energy consumption from your 12V fridge.
How much power does a fridge need?
There are a lot of different factors that affect the energy consumption of a 12V fridge. Size, compressor style, ambient temperature, insulation thickness, the temperature they are set to cool to, what you are using it for, and the list goes on.
However, most will consume in between 1 amp and 6 amps (with 2.5 amps being fairly average) an hour when running. However, a fridge won’t usually run 100% of the time, so it only pulls that current when the compressor comes on.
Most fridges are loud enough for you to hear them within a few metres. Again, the cycle time varies considerably, but on average they run about 50% of the time.
Using the above example, where the fridge draws 2.5 amps when the compressor is on but only runs for 1/2 the day, it will use 30 amp hours of the battery capacity.
What battery should a fridge run off?
Fridges should never run off the cranking battery that you use to start your vehicle. The only exception to this is while you are driving if you absolutely must. The reason behind this is simple – your cranking battery is imperative to start your vehicle, and if you run it flat you can be in serious trouble.
The most common way to run a camping car freezer is with a second battery, which is isolated from the main cranking battery. The best option is a deep-cycle battery, which is designed (as the name suggests) to cycle from full to half empty and back again, anywhere from 1200 – 1700 times.
You can run them off a normal cranking battery, but they don’t like to be cycled and you will shorten its life substantially. Lithium batteries are also becoming more popular as they have several advantages, but they come at a pretty hefty cost.