How to Conserve Energy at Home

Here's a no-cost, minimal-labor tip that reduces air infiltration into and out of your house during both summer and winter. It also helps provide better security for your family. Lock your windows!

That's right. Just a simple trip around the inside of your house to be sure all the window locks are engaged can save energy. The reason? Most windows, both casement and double-hung types, are made with compressible weather stripping that helps seal out air infiltration along the edges and between the upper and lower sash. The locks on casement windows draw the sash closer to the frame (in the case of double-hung windows, they're closer together in the middle), and that compresses the weather stripping, creating a more airtight seal.

Windows are designed to provide light and ventilation. They should also seal well in order to prevent air and water leakage. If your windows aren't locked when they're not open, you're not using one of the features that contribute to their energy performance. Here are more ideas on how to conserve energy around the house.

Watch Water Heater Temperature Settings

The cost of heating water for your home may amount to as much as 15 to 20 percent of your entire utility bill. Setting your water heater's temperature in the 130-degree range instead of a higher one requires less energy to heat and to hold the water. Every 10 degrees you dial down the thermostat can knock 3 to 5 percent off your water-heating bill. In addition, a lower hot water temperature reduces the chance of scalding.

By setting your water heater to 130 degrees, you should produce 120-degree water at the tap, which is low enough to prevent injury but still hot enough to produce a satisfyingly warm shower or bath. There is always some heat loss in the piping between the water heater and the fixtures where the water is used, so that's why the water heater's temperature should be in the 130-degree range, which is also sufficiently hot to prevent bacteria from growing inside the water heater's tank.

Gas and oil water heaters can be adjusted easily by turning the dial thermostat on the front of the control box. There may be degree markings on the dial, but many have simple arrows that point the direction to "hot" and "not-so-hot" settings. You might have to experiment by gradually turning down the dial over the course of several days in order to arrive at a setting that feels comfortable to you and your family.

Adjusting the temperature setting on an electric water heater is slightly more complicated and may require removing coverings over the heating elements. Small screws attached to the elements can usually be turned to the temperature of your choice. Most have painted or engraved temperature reading marks on the screw housing. Both heating elements must be dialed to the same degree reading or one might never activate. Check your owner's manual before you adjust an electric water heater to ensure you're following the proper procedure for your particular model. Be sure to shut off the power before you remove any protective cover plates.

It may require a day or so for the water in any type of heater to stabilize to the new temperature setting after an adjustment has been made to the thermostatic control. Test the water temperature by running a tap until the water is hot, then fill a glass with the water. Put a thermometer in the glass, and take a reading.

There are other good reasons to dial down your water heater's thermostat. Higher water heater temperatures can contribute to early failure of the tank. Because chemical reactions are speeded up in hotter environments, rusting of the steel tank is accelerated under high temperature conditions. Plus, sediment (hard-water minerals) precipitates out of hard water more rapidly in hotter conditions. It collects at the tank's bottom and reduces the energy efficiency of the water heater. For energy savings, safety, and equipment longevity, dialing back your water heater thermostat to 130 degrees or so (about 120 at the tap) makes sense.

Dial Down the Thermostat At Night

While the concept of dialing down your house temperature a few degrees during your home's occupied hours is helpful in terms of energy conservation, it's at night and when you're away from the house that you can turn down the thermostat even more, thus significantly reducing your energy bill.

The question often arises, "How long does the thermostat have to be at a low setting in order to save enough energy to make up for what it takes to get the house back up to temperature when you dial the heat back up?"

Experts at the Department of Energy have determined that the amount of energy saved as the temperature falls in a house after the thermostat is dialed down is approximately equal to that used to get the house up to temperature again. The actual energy savings in a dialed-down session occur during the time when the heat is operating at its lowest setting. At that point the heating system does not have to work as hard to maintain a large indoor temperature differential compared to the outdoors.

In other words, the amount of energy saved by turning down the thermostat makes up for the energy used in turning it back up. Meanwhile, any hours spent with a smaller temperature difference between indoors and outdoors results in the system not having to come on as often; that's where the savings lie. And the lower you dial, the more savings you can realize.

HVAC experts estimate that for every degree the thermostat is dialed down, you can save 1-3 percent on your heating or cooling utility bill. And when you count up the many hours you're either in bed or the home is not occupied, there is considerable potential for savings.

Digital Thermostats: In recent years the marketplace has seen an influx of sophisticated, programmable digital thermostats that assist periodic dialing down, or temperature "setback." For an investment of $40 to $100, these thermostats can be programmed to automatically dial down the heat at a certain time at night or when you're away from the house and to turn it up again before you awake in the morning or arrive home. The automated features of a digital thermostat ensure that you will never have to dial back the heat at night manually, and you can wake up to a house that is up to its normal temperature in the morning.

Digital thermostats are also more accurate than the older-style mercury switch units; they can differentiate room temperature down to a fraction of a degree. This precision results in more exact control of the HVAC system, eliminating large temperature swings, and thus delivers better comfort -- as well as energy savings -- from the setback function. The programming features can also help in the summer when setting the thermostat to allow the temperature to rise in the house while you're away (in order to avoid having the A/C come on as often) saves energy.

Basic digital thermostats might allow you to program time and setback temperatures using two schedules -- one for the five-day work week and another for the weekend. Higher-end models pack more options and sophisticated features, such as the ability to program different setback and wake-up settings separately for every day of the week. This can be helpful if you need to rise at different times on different days. And all digital thermostats can be over-ridden at any time to accommodate a specific need, such as a house full of people you'd like to keep cool during a summer party.

If you're thinking of investing in a digital thermostat, be aware that there are several types to fit different configurations of HVAC systems. The thermostat must fit the system in order to work properly. You'll have to know how many wires run to your old thermostat in order to match it with the new digital model.

As a side note, if an old thermostat you're replacing has a mercury switch (look for a small glass vial inside that holds a silvery liquid), it must be handled carefully to avoid breakage and be disposed of properly. Mercury is a toxin and an environmental hazard! If the manufacturer of the thermostat you purchase doesn't directly engage in a recycling program, take it to your nearest hazardous material recycling center.

Manual thermostats: If you're not technologically inclined, or if your schedule is variable and you don't go to bed and get up at predictable times, there is another "digital" thermostat adjustment device available to you that works reasonably well. And it doesn't cost a thing! In fact, it involves using the digits on your hands.

Even an unsophisticated manual-type thermostat can be made to operate like a programmable one if you remember to set the temperature back every night and dial it up again in the morning. The one drawback is that your house will be cool when you wake up.

For many people, setting a manual thermostat up or down as they leave and enter the house, or go to bed and wake up, becomes a habit that is easy to remember. For others, the automated setback features offered by a digital thermostat make that option more convenient. Digital or manual, the main point is that any time you turn down the thermostat in your house (or turn it up in the summer), you save energy.

A fireplace can give the comfort of a crackling blaze in the heart of winter, but you'd be surprised to learn how much heat escapes and how much energy is wasted when you have a fireplace in your home. Check the next section for tips on making your fireplace help, not hurt, your energy bill.