There are two types of All-Electric Compressor refrigerators
One is the typical RESIDENTIAL type 100-300 watts running. Starting can be over 500 to 1000 watts.
The other is the high effiency or "Danfoss class" (Danfoss is one of the companies that make this type of compressor. there are others as well)
Norcold and Dometic both offered units of this type.. As do other companies in other formats.. For example I have an aux freezer that is 13 years old and of this type (it is a chest freezer about the size of a 35-40 gallon ice chest type cooler but not as big inside) These units typically run on 12 or 120 volt via a power conversion system and inverter on board.. Typically draw 30 to 50 watts running As I said mine is 13 years old. I run it on 12 volts. unless there is a issue on the 12 volt side of life than I run it on 120.
Very happy with it.