What's the single biggest user of electricity in my house?

If your house has central air conditioning, the air conditioner will probably be the biggest user by far. Although used only a few months of the year, the annual cost can be much greater than the annual cost of your refrigerator, which is typically the next largest user. In hot climates, the annual air conditioner cost can exceed a thousand dollars. You can get a very rough idea of what your air conditioner is costing you by subtracting the electric portion of your bill in a spring month when you aren't using your air conditioner from the electric portion of the bill in the summer when you do use it. This gives you the monthly cost. Multiply this by the number of months you use your air conditioner to arrive at your approximate annual cost.

Refrigerators are typically the largest users in houses without air conditioning or in climates where the air conditioners are used only a few days of the month during the cooling season. If your refrigerator is more than ten years old should consider replacing it. New efficiency standards went into effect in 1992, and older refrigerators are typically two to three times more expensive to run than a new unit.

 

What's the most common mistake people make in trying to save energy around the house?

Common mistakes people make include:

  • letting the furnace or air conditioner salesperson sell them a unit that's much bigger than they need,
  • not getting the ducts checked for leakage when installing a new heating and cooling system,
  • thinking that "since heat rises, we only need to insulate the attic." Floors over a basement or crawlspace, walls and windows also matter.
  • not using ceiling and portable fans to improve comfort in the cooling season. They use very little electricity. Use them to circulate air in the house, tomake the house feel cooler by doing this, the thermostat setting for your air conditioner can be raised to 85°F, and still maintain the same comfort as the lower setting.

 

Why are my bills so high?

There are a number of factors that cause differences in energy bills, so comparing your bill to someone else's is like comparing apples to oranges. 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, and hobbies which result in electricity use.