Use natural daylight when possible. Avoid using small appliances whenever possible. Use small appliances instead of larger ones whenever possible. Use appliances that have a lower wattage. Be sure seals around refrigerator and freezer doors work properly.
Freezers work most efficiently when full.
Refrigerators should be full but not overcrowded. Air circulation is needed. Set the refrigerator and freezer at the highest possible settings that will still preserve food quality. Cool foods to room temperature before putting them in the refrigerator. Cool foods in the refrigerator before placing them in the freezer.