Does an empty fridge/freezer require more power to stay cold than a full one?
The efficiency of a fridge/freezer is directly connected to the penetration of heat into its contents. Heat enters the fridge/freezer and the fridge/freezer has to pump it out. Pumping heat requires energy and the more ingress and egress takes place, the more energy the fridge/freezer requires to cool.
More stuff in the fridge/freezer gives it a higher heat capacity so that it doesn’t warm-up so much when the door is opened. However, it will take considerably more energy to cool it initially from room temperature. A full fridge performs ‘less’ cooling cycles over time.
A full fridge/freezer retains cold better than an empty one. when you open the door, the mass of frozen food will help keep in the cold and the unit won’t have to work as hard to cool an empty space. Do not jam-pack the fridge/freezer either since we need air circulation as cooling takes place.
The efficiency of a fridge/freezer will also be determined by how old or new the fridge/freezer is. Older fridge/freezer models will consume more energy than newer models. And when a fridge stops working, it will use more electricity as it struggles to maintain a cool temperature despite a malfunctioning compressor, a tired motor and leaky seals. Families that replace their old refrigerators notice immediate savings on their energy bills.