Cover liquids and wrap foods stored in the refrigerator. Uncovered foods release moisture and make the compressor work harder.
Don't overfill your refrigerator or freezer. Cool air needs to circulate freely. To make it work more efficiently, vacuum the condenser coils once a year (according to the safety instructions in your owner's manual) unless you have a no-clean condenser model. Your refrigerator will run for shorter periods with clean coils.
If you have a manual-defrost refrigerator or freezer, defrost it regularly - frost buildup increases the amount of energy needed to keep the motor running. Don't allow frost to build up more than one-quarter of an inch.
Make sure your refrigerator door seals are airtight. Test them by closing the door over a piece of paper or a dollar bill so it is half in and half out of the refrigerator. If you can pull the paper or bill out easily, the latch may need adjustment or the seal may need replacing.
Refrigerators use more energy than any other single appliance in your home. If your refrigerator is 10 years old or older, consider replacing it with an Energy Star-qualified refrigerator; it will use less than half the energy of your old unit.
Setting your refrigerator or freezer temperatures too cold wastes energy. For better efficiency, keep your refrigerator at 37 degrees Fahrenheit to 40 degrees Fahrenheit for the fresh food compartment, and your freezer at 5 degrees Fahrenheit. If you have a separate freezer for long-term storage, keep it at 0 degrees Fahrenheit.
When buying a new refrigerator, look for one with automatic moisture control - it prevents moisture from accumulating on the cabinet exterior without having to add a heater.
Your refrigerator cools food but heats your kitchen, so keep the door closed as much as possible.