Keep in mind, boats and any food / alcohol service have strict guidelines and regulations. You could probably get some large battery packs charged by a generator. Look at other people who have similar setups. You could probably find out a lot by looking at an ice cream truck.
I tell you what, first go find somebody that s already doing it, and ask your questions. You want to run a restaurant from a boat? Put a gas operated generator in your engine bilge, and drop your electric cords down there, you don t want the smoke/smell of generator wrecking your sales. You ll need a very large Solar panel to run a mini fridge! Go check your specifications.
