Storing beer in fridge through winter in garage?

Hey everyone, I have a garage without heat and I have a lot of pretty good beer stored in there inside a refrigerator. I just got this refrigerator this summer and I am worried that if the temperature gets too cold, up here in Wisconsin they can get down to 0°F at times, that the beer I have in there could freeze if it gets too cold. Does anyone have experience with this or had any advice? The temperature inside the garage doesn't quite get down to outside temperature, but it's pretty dang cold. Does the refrigerator provide enough insulation in itself to keep the beers safe. Most of these are bombers and are fairly high abv.

 

Thanks, i was thinking about unplugging it because it really doesn't need to run at all anyway, but my main concern was how much insulation the fridge provides when the outside temp is around 10 or under and how long it takes the inside to match the outside temp.