Unplug that spare refrigerator in the garage and only turn it on when you truly need it - this seemingly convenient way to keep extra drinks cold can add 10-25% to your electric bill.
To check refrigerator temperature, place an appliance thermometer in a glass of water in the centre of the refrigerator. Read it after 24 hours. To check the freezer temperature, place a thermometer between frozen packages. Read it after 24 hours.
Don't set the temperature too low. A change of one degree can effect energy consumption by 5%. Freezers should operate at -15oC to -18oC while fresh food compartments should be held at around 3oC to 4oC.
Choose a cool position. Placing a fridge or freezer in direct sunlight or next to an oven or other heat source can increase energy consumption substantially.
Regularly defrost manual-defrost refrigerators and freezers; frost buildup increases the amount of energy needed to keep the motor running. Don't allow frost to build up more than 6mm.
Make sure your refrigerator door seals are airtight. Test them by closing the door over a piece of paper so it is half in and half out of the refrigerator. If you can pull the paper out easily, the hinge may need adjustment or the seal may need replacing.
Move your refrigerator out from the wall and vacuum its condenser coils once a year unless you have a no-clean condenser model. Your refrigerator will run for shorter periods with clean coils.
Make sure there's plenty of air flow around the back (>8 cm gap); if the fridge is installed in a specially built alcove or cupboard, make sure there's good ventilation out of the top as well. Restricting ventilation could add 15% or more to the fridge running cost.
Allow food to cool before putting it in the fridge (but don't let it sit at room temperature for too long – this could be a health risk).
Cover liquids and wrap foods stored in the refrigerator. Uncovered foods release moisture and make the fridge work harder.
Food should be placed slightly apart on refrigerator shelves for correct air circulation
In freezers, food packages should be scattered and should never be grouped or stacked together until they are completely frozen.
Turn off, empty, clean and leave refrigerator door open when you are away for an extended period.
Do not open the refrigerator or freezer door needlessly. By removing or replacing several items at a time, you can protect the cold air inside the fridge and save energy.
Choose a refrigerator or freezer that's right for your needs. Refrigerators and freezers operate at peak efficiency when filled to the correct capacity.
If you're going to throw out your old fridge, see if there's a chlorofluorocarbons (CFCs) recycler in your area. The government department which looks after the environment in your area may be able to help you.