I do not know. Mine are Uni-Solar panels that are much larger than the average panel, size wise. If there is power available the best bet is a grid tied system (read, no batteries, no rewiring to 12 volt). Costs for panels are hovering around about $1.00 per watt.
Kustom Koach Class C 28'5", 256 watts Unisolar, 875 amp hours in two battery banks 12 volt batteries, 2500 MSW watt inverter.
My experiment got interrupted but the results were clear.
Cool down time defined as fridge starts to cycle.
14 hours cool down time without external fans (4.2 kwh)
8 hours cool down time with external fans (2.4 kwh)
5 hours cool down time with external fans and "blue ice" bricks in the freezer. (1.5 kwh)
While I have not ran test on ours but I run propane and I usaly use Ice cubes in both freezer (1 gallon zip lock bag) and fridge (1 gallon zip lock bag 1/2 full) plus item we put in it, so using it as an ice chest at first more or less.. I usaly have about 2 hr pull down time to about 42 degrees. Also the Ice cubes in the freezer are used as ice cubes as they do not melt.. Most times however we start it in the morning when we come up with some reason to go and depart with in an hour of starting it..
We spent most of our money traveling... Just wasted the rest..