I am not sure exactly how many watts are drawn in a time period, but I do know that it is not energy start compliant, so it uses more energy that a normal miniature fridge. It is also thermoelectric cooled, so it has metal plates that get cold, not cold air circulation.
There is a device that can be purchased from a hardware store that will tell you exactly how much power this lil fridge/cooler is pulling.
hope this was helpful