@pookysimslover You can store food in any refrigerator off the grid, I was able to do it no problem. None of the refrigerators say they can be used off the grid, but they can...somewhat. You'll be able to 'cook' regular salad and fruit salad, that's it, and store food. If you have one of the stoves that say they work off the grid, you can make a couple dishes (eggs & toast and I think grilled cheese is what it showed, but perhaps you can make more with higher cooking skill. Her Sim was brand new) when you 'cook with gas' on them. You need a fridge to use it though or else you can't do anything with the stove for some reason.
I saw a YT by the UKSimmer that showed this information about the stove. My Sim didn't have a stove, he just ate salads and fresh produce. I haven't had him use the grill yet since he's a vegetarian. Although, he could make grilled fruit on it I guess. :)
EDIT: Obviously you need a counter to prepare the food as well.
Source: She realizes she can use the refrigerator and cook dishes around the 19:40 mark, so towards the end if you don't want to watch the entire video.
https://youtu.be/EAyIIxO7prw