The relatively efficient refrigerators with Danfoss type compressor (Engle, Truckfridge, etc) probably would use about the same amount of power as that little 12V cooler, and would keep food as cold as you wanted it; they can even function as freezers. As far north as you are, you have a greater sun angle and probably a fair bit of cloudiness, so to support such a device you'd probably need 150-200W of solar
panels and you would benefit from having a pair of batteries to go with the solar
. I would not rely on the vehicle battery
, because it isn't made for that kind of usage (although while driving it would work out fine, just not while camped).
I have looked and thought and debated with myself, and over the years I have come around to the traditional ice chest cooler for extra cool-food storage. A basic Coleman Extreme is affordable and can keep stuff suitably cold for about 4 days (maybe longer with your cool nights). A rotomolded cooler like the Yeti will stretch that to about 6 days, for a price of course. How long you camp without access to more ice would dictate which one is better for you. For the price of a decent fridge
you can buy (or make!) a lot of ice. Here is a link to the recent thread about coolers here on FGRV... http://www.fiberglassrv.com/forums/f...hts-78692.html
cooling (not that you've indicated trouble), one easy thing to check is the tightness of the door gasket. I've read that if you close the door on a dollar bill and can pull the bill out with ease, the gasket isn't sealing very well. A new gasket shouldn't break the bank.