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 and your neighbors house was recently 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, the number of loads of laundry, and hobbies that result in electricity use.
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.
The rate of heat transfer from your house to the outside, or vice versa, is dependent partly on the temperature difference between your house and outside. More heat is transferred when the difference is greater, so it takes more energy to keep your house at 72 degrees when it is 40 degrees outside than to heat your house back up to 72 degrees after you return. With air conditioning systems, the equipment runs at peak efficiency when it operates for long periods. Cooling your house back to the comfortable temperature will use less electricity than the unit would use cycling on and off for short periods to maintain the set temperature. If your house takes too long to get back to a comfortable temperature, you might investigate getting a programmable thermostat, and set it to start heating or cooling your house an hour or so before you return.
The best way to prevent drafts in your house is to stop the air from penetrating the outside shell. Typically, air comes in through cracks along the foundation, near the exterior of the chimney, water faucets and electrical outlets, and along doors and windows. A good quality outdoor caulk will prevent airflow through these areas. For cracks larger than ¼ inch, fill the gap with insulation or some other filler material, and then caulk over the area.
This problem is probably caused by disconnected or leaking ducts, which will reduce the amount of conditioned air reaching a room. Ducts can become disconnected or develop leaks in many different ways. One is accidental bumping, which happens when someone moves around the ductwork. In addition, over time duct tape can degrade and ducts can fall apart. Disconnected ducts are not only a problem in older houses, but also in new construction where the ducts can accidentally be jarred loose. Have your ductwork inspected and make sure any connections are airtight, and held together with sip ties, or sheet metal screws and mastic to create a good seal.
Typically, water heaters have three temperature settings — high, medium and low. These settings correspond roughly to about 160 degrees for high, 140 degrees for medium and 120 degrees for low. Most people have the temperature set to medium, or around 140 degrees. The most efficient setting is 120 degrees, or low. You will save about 3 to 5 percent in water heating costs for 10 degrees of reduction. You also might want to consider a timer for your water heater that turns it off when not in use and investing in a wrap that will help insulate the heater so it stays warmer longer.
Yes, there’s a new kind of fluorescent technology, called “electronic ballasts” that eliminate the annoying hum and flicker of traditional fluorescent lights and that emit a much warmer, natural light. When purchasing fluorescent bulbs look for the Color Rendering Index (CRI) and the Correlated Color Temperature (CCT). Bulbs with a CRI rating of 80 or higher will better render objects true color when compared to sunlight. The CCT refers to the color objects emit when heated to a certain temperature. The lower numbers correspond to reddish color and the higher ones to blue-white color. For color similar to incandescent lighting look for CCTs around 2700.