On boats, the compressor fridge is the standard. Mostly for safety concerns.
I have a couple chest type compressor fridges. Essentially the size of a large cooler. They work very well, but average 1-2 amp/hrs. Yes, they are idle a good bit of the time, but that is the average consumption.
The trend in the Class A market is these huge residential style fridges. Their consumption is much higher and requires a huge battery bank. You can do a search and read about all the issues. Primarily draining down the batteries, etc. The fridge itself is reliable, but the users usually screw up and run their batteries down. I just don't get the desire for a ginormous fridge.
Of course in the B class,such appliances are not possible. What you can get is similar to what you get on boats. So 2 to 3 amp/hr on average, depending on size. As long as you have a big battery bank, and some management skills, refrigeration is not really an issue. It's when you add cooking and using air conditioning to the mix, you are really pushing a DC system to the max.
