Refrigerators for cabins and RVs can be LP gas or electrically-powered (ideally by solar). Cabins usually have roof space for the 200-300 watts solar capacity required. Also feasible are portable solar modules placed outside when you use the cabin. RVs less available space for solar modules. Buy only the efficient monocrystalline.
Solar That Really Works!
Solar that Really Works! covers the design, installation and use of solar in cabins, camper trailers, caravans, fifth wheelers, campervans and motor homes.
Any bookshop, whether online or bricks and mortar, can order copies of Solar That Really Works! Just ask.
Caravan & Motorhome Electrics
The essential handbook for anyone with an RV of any kind. Everything you need to know to make the electrics in your rig work for you.