I suggest the OP goes on line and finds the handbook for the Fridge (the model number is usually found on a label inside the fridge low down on one side.) This should say exactly how much gas it uses. The important thing is to keep the fridge as full as possible, then it will use significantly less gas when the contents are frozen (or near that.)
From an electrical point of view, under counter fridges usually draw about 120W, tall fridges pull more in the range 160-180W. However on mains they are thermostatically controlled so the power draw may be much less than continuous.
From an electrical point of view, under counter fridges usually draw about 120W, tall fridges pull more in the range 160-180W. However on mains they are thermostatically controlled so the power draw may be much less than continuous.