The ages of major appliances, especially refrigerators and air conditioners, can make a dramatic difference in your bill. In addition, if your house leaks air like a sieve while your neighbor's house was just weatherized and insulated, you will have much higher heating and cooling bills.

Other factors that can result in significant differences in bills are:

• The number and kinds of lighting fixtures;
  
• Thermostat settings for heating and cooling;
  
• The number of loads of laundry;
  
• Old refrigerators out in the garage;
  
• Hobbies which result in electricity use.

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