This is an interesting thread for a solar newbie like me and timely too as I will be camping for 4 nights next week and trying solar for the first time. I'm sure some of what I will be using is "wrong" and that I'll learn from the experience. No doubt I'll be making some adjustments for a similar trip next month.
I would like a dual battery set up but I camp with 2 different Jeeps, my LJ or XJ, and I don't want to modify both if there is an alternative. I take I of 2 trailers. My tear drop has a Group 31 deep cycle battery that I charge ahead of time and while I driving. It has run the trailer just fine up to now (basically LED lights, nothing else). I have just added a water pump for an on demand water heater. The water pump needs 12V DC power - the heater doesn't. I'll also be running a 12V DC 40 litre cooler. A "real" 12V fridge is in the future. I precooled the cooler and ran it for about 6 hrs. yesterday off of a 12V car battery hooked up to a 100W solar panel. I was able to maintain 38*F with no draw down on the battery.
I also have a 2,000W 700 amp power box that I'm going to try out today. It can be charged using the same solar panel. I'm hoping this will come in handy as a back up and for day trips that I take. If it's useful in lieu of a dual battery set up in the above 2 Jeeps plus my MJ for day kayaking trips … great!
I usually pack my dry food in a large plastic ammo box. This time I'll be using a Coleman cooler. If my 12V cooler can't keep up or simply fails, it will become the dry food storage bin and I'll be looking for some ice for the cooler!
I really need to map out all of my power sources and demands and try to make sense of it. I found
thomat65's post very helpful in that regard. I should probably take a calculator with me next week. One with its own battery of course.