Saving Energy

With energy bills skyrocketing in recent years, the need to save energy has become more important than ever, according to the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE).

Saving energy translates into money savings for homeowners. In addition, saving energy is beneficial on a global scale, since the world faces dwindling energy reserves.

As homeowners struggle to keep their homes warm and comfortable, saving energy becomes more difficult. Space heating accounts for 49 percent of the energy used in residential buildings in the United States. According to professionals in the design community, there are fairly easy ways to save energy.

Set thermostats at 68°F (20°C)
when the house is occupied during the day and at 60°F (15°C) at night. Programmable thermostats can do this automatically and easily. They are inexpensive, reliable and easy to install.

Do not set back a heat pump’s thermostat manually if it causes the auxiliary heating to come on (or disable the auxiliary heating). This type of heating, which is often used as a backup to the heat pump, is more expensive.

Clean or change furnace filters once a month or as needed, and have the system maintained according to manufacturer’s instructions. Dirty filters, coils and fans reduce airflow throughout the system, which decreases performance and can damage your system.

Check ducts for air leaks. Look for sections that should be joined but have separated, then look for obvious holes.

If you use duct tape to repair and seal your ducts, look for tape with the Underwriter’s Lab logo to avoid tape that degrades, cracks and loses its bond with age. If you are not sure which tape is recommended for your ducts, contact your heating, ventilation, air-conditioning and refrigerating contactor. Remember that insulating ducts in the basement will make the basement colder. If both the ducts and the basement walls are uninsulated, consider insulating both. Call your HVAC&R contractor to help you assess the need for additional insulation and to insulate and repair all ducts, if needed.

Insulate. ASHRAE recommends, depending on climate zone, between R-30 and R-52 in the attic space (R-13 and R-21 for cathedral or flat roofs), R-13 and R-21 for walls, and between R-13 and R-30 in floors. Adding insulation to your attic is easiest and least expensive. Insulation can be blown into wall cavities, especially in older homes with little wall insulation. If siding is to be replaced, take the opportunity to add a layer of exterior insulation.

For windows, ASHRAE recommends:

• Double-glazing (quarter-inch air space) with non-metal frames (or metal frames with a thermal break) for warm climates, coupled with summer low-e coating on the glass to reduce the transmission of the sun’s rays during the cooling season;
• Double-glazing (quarter-inch air space) with non-metal or insulating frames, plus a winter low-e (e less than 0.2) coating, for moderate climates;
• Double-glazing (half-inch air space) with nonmetal or insulating frames for cold climates, coupled with a winter low-e (e less than 0.05) coating on the glass to retain more internal heat.

Achieving these levels may require replacement windows, which although expensive, can be a sound investment for homeowners. Storm windows should be considered in colder climates.

Caulk, install weather stripping or use spray-in foams around windows and doors, on exterior walls, or between heated and unheated spaces garages, basements, crawl spaces, attics) to keep cold air out and conditioned air in.

During the heating season, keep draperies and shades open on your southern facing wall during the day to allow sunlight to enter. Keep them closed at night to reduce the chill you may feel from cold windows.

Use kitchen, bath and other ventilating fans wisely. In just one hour, these fans can pull out a houseful of heated air. Turn fans off as soon as they have done the job. Excess moisture is not a bad thing in winter, when indoor air tends to become quite dry. Owners may wish to consider installing a timer switch instead of a manual switch to limit the unnecessary operation of an exhaust fan.

When you use the fireplace, reduce heat loss by opening dampers in the bottom of the firebox (if provided) or open the nearest window slightly – about 1 inch - and close doors leading into the room. Lower the thermostat setting to between 50°F (10°C) and 55°F (12°C). Install tempered glass doors or a heat exchanger system that blows warmed air back into the room. Check the seal on the flue damper and make it as snug as possible. Add caulking around the fireplace hearth. Use grates made of C-shaped tubes to draw cool room air into the fireplace and circulate warm air back into the room.

Insulate your hot water tank with an insulating jacket according to manufacturer recommendations. Some newer tanks already are insulated so check product literature to determine if insulation is needed. Insulate the first six feet of the hot water pipes connected to the water heater.

Many local energy companies offer rebates and incentives for energy conscious purchases or home improvements. Contact your local energy provider for information on how to take advantage of these programs.

Select energy-efficient equipment when buying heating and cooling equipment. Your HVAC&R contractor should be able to give you energy fact sheets for different types, models and designs to help compare energy usage. Look for high annual fuel utilization efficiency (AFUE) ratings, heating seasonal performance factors (HSPF), and the seasonal energy efficiency ratio (SEER). The national minimums are 78 percent AFUE for furnaces and 13 SEER for air conditioners as of Jan. 26, 2006.

Make sure supply and return vents are not obstructed by furniture, appliances or other objects so that air can flow freely. This maximizes efficiency of the system and helps distribute warm air throughout the room.

Close unoccupied rooms that are isolated from the rest of the house and turn down the thermostat or turn off the heating for that room or area. However, do not turn the heating off if it adversely affects the rest of your system or could lead to freezing water pipes. Sink cabinet doors should be opened to keep water pipes from freezing.

ASHRAE is the world’s foremost technical society in the fields of heating, ventilation, air conditioning and refrigeration (HVAC&R). The Society helps keep indoor environments comfortable and productive, deliver healthy food to consumers and preserve the outdoor environment. ASHRAE’s technical foundation is built by some 50,00 volunteer members, including 6,458 student members, in more than 133 countries with some 170 chapters and 212 student branches. ASHRAE membership includes consulting engineers, contractors, manufacturers, manufacturing representatives/sales, and architects.