Did you know that most of the energy used in your freezer is used by cooling the warm air that flows in when the door is opened. A way to deal with this is to keep your freezer filled to capacity so less air can seep in. If you are on the sparse side in the frozen food area, fill freezer bags with packing peanuts to make up for the barren areas and mold into the empty spots. You’ll save about $40.00 in energy costs per year with a full freezer.