Being off grid can be a lot of fun and it can be very relaxing, but modern conveniences like refrigeration can be difficult to deal with. Long road trips where you don't use a hotel room and you're running off of your car and gas can be fun, too, but eating out all the time can get expensive.
If you want to travel comfortably and be able to keep food cold in the car, you're going to want a portable fridge/freezer combo unit. The ARB portable fridge freezer fits this need quite nicely and is available in multiple different sizes for your convenience.
Instead of getting a $400 Yeti cooler that's incapable of cooling itself, pick up an ARB instead. Large, luxury coolers are great to have until all of the ice melts. After that, you're left with a 23lb brick that doesn't do anything but hold spoiled food.
The best thing about the ARB fridge freezer is in the name: it keeps frozen things frozen. It takes a while to freeze things that aren't already frozen, but it's designed to keep ice and frozen foods below freezing or in refrigerator mode, everything nice and fresh So, if you want to load it up with ice so you can keep drinks in it cold for days at a time, that's a great use. But, it's also great to keep sandwich meat, mayonnaise, etc in for road trips.