ENERGY EFFICIENCY
IN YOUR HOME
ENERGY EFFICIENCY
IN YOUR HOME
Doing laundry is one of the most energy-intensive activities in the home. The average American household spends about $150 annually to run its clothes washer and dryer. Miscellaneous appliances and household electric gadgets-everything from TVs and hair dryers to waterbed heaters and hot tubs-add another $200 a year to the average electric bill.
Most of these appliances can be operated more efficiently and cheaply without any loss of performance-indeed, certain efficiencies can actually produce cleaner, fresher clothes. And, as with almost all appliances, newer models coming on the market feature energy-saving options that can make them even cheaper to run.
WASHING MACHINES
Since heating the water to wash clothes accounts for most (85-90%) of the energy demand, minimizing the use of hot water is a simple way to reduce energy use-and utility bills.
Operating Your Washer Efficiently
As the table below shows, low-temperature washing saves a good deal of energy and money. Warm water is effective for washing most loads (though not for oily stains); a warm pre-soak may be necessary for really dirty clothes, but this is still more efficient than a hot-water wash cycle. Cold-water washing can be adequate in many cases, especially if you use an enzymatic detergent. Regardless of the wash temperature, always select the cold-water rinse-warm or hot water in the rinse cycle doesn't make clothes any cleaner. Colder temperatures are easier on your clothes, too.
Here are a few other tips for increasing energy efficiency:
Wash full loads. If you don't have enough dirty laundry to fill up the washer, adjust the setting to a lower water level. Using the small-capacity setting can cut water use by up to 50%, Locate the washing machine close to your hot water tank, if possible, to reduce the heat lost in long pipe runs. Insulate exposed pipes. Turn your hot-water heater thermostat down to 120°F, if it isn't there already. Each 10°F reduction in water temperature will cut the cost of washing clothes (and everything else requiring hot water) by up to 13%.
New Washers
Energy efficiency should be a major consideration when shopping for a new washer, since an efficient model can pay for its extra cost in just a few years (the average lifespan is 13 years). Energy Guide labels (see next page) are helpful in estimating energy costs, although their estimates are based on standard cycles without the use of optional energy-saving controls. Also note that while compact models rate well, they are designed to wash smaller loads-it's still more efficient to do one full standard-size load than a couple of compact washer loads.
In the past decade, the energy efficiency of standard top-loading washers has doubled. Most new models offer various controls over wash and rinse temperatures, load size, and presoak cycles, and some also feature a "suds saver" option that saves soapy water from one cycle to the next. Certain high-end machines automatically sense load size, the dirtiness of the water, and even fabric type, and adjust the water level and wash cycles accordingly. It's also worth looking for a model with a faster spin speed, which extracts more water so less energy is needed for drying (if you use a dryer).
The vast majority of domestic washers sold in North America are vertical-axis machines, meaning that the washing drum is mounted vertically and clothes are loaded from the top. Horizontal-axis (H-axis) washers use 30-60% less water and 50-70% less energy because the horizontal drum tumbles the clothes through the water at the bottom, permitting a much lower fill level. Other advantages are lower drying costs (thanks to faster spin cycles), less detergent use per load, and better performance.
H-axis machines are popular in Europe, and it's likely that they will become the norm in the U.S. during the next decade as manufacturers push to meet federal efficiency standards. In the meantime, they cost at least $200 more than comparable V-axis models. Frigidaire manufactures an H-axis washer for White-Westinghouse and Gibson, Maytag and Whirlpool will enter the market by 1996, and Staber Industries has developed a top-loading H-axis model. A few European front-loading models (AEG, Mieli, and Asko) are available in the U.S., although they're considerably more expensive.
CLOTHES DRYERS
Clothes dryers account for 5% of all domestic electricity use. In homes that have one, the dryer is typically the second-biggest electricity-using appliance after the refrigerator, costing about $85 a year to operate.
Even if you live in a damp or cold climate, strictly speaking, a clothes dryer is an unnecessary appliance most of the time. Drying clothes outside on a line performs the same function without using fossil fuels or generating pollution-and it's free. Unless it's actually raining or the temperature is well below freezing, your clothes will generally dry in a day or less. They'll also smell fresher and last longer. In wet or cold weather, you can still bypass the dryer by hanging clothes inside, although this isn't advisable if your house has a moisture problem.
Dryer Efficiency
Your clothes dryer need not be such an energy hog. Here are some tips for operating it more efficiently:
Run only full loads, as small loads are less economical. However, don't overfill the machine-air needs to be able to circulate around the clothes.
Dry heavy clothes separately from light clothing.
Dry two or more loads in a row, to make use of the heat already in the dryer.
Don't overdry clothes. If your machine has a moisture sensor, use it. If it has a timer, consider shortening the drying time.
Use the cool-down cycle (if there is one) to allow the clothes to finish drying with the residual heat in the dryer.
Clean the fluff out of the filter before (and, if necessary, during) every load to allow air to circulate better. Regularly clean the lint from vent hoods and lint kits, too.
Check the outside dryer vent. If it doesn't close tightly, replace it with one that does (a new one will cost $15-$20). You'll keep outside air from leaking in, reducing heating and/or cooling bills.
If you have an electric dryer, install a lint kit ($5-$10) to vent the exhaust heat and humidity into the house in winter-an easy project. (Exhaust fumes rule out this option for gas dryers.)
Locate your dryer in a heated space. Putting it in a cold or damp basement will make the dryer work harder to get your clothes dry.
New Dryers
New dryers aren't required to display Energy Guide labels, making it hard to compare the energy efficiency of different models in the showroom.
The single biggest factor in determining a dryer's energy cost is whether it runs on electricity or natural gas. Although gas dryers are slightly less efficient than electric ones, gas is much cheaper than electricity in most parts of the country, and burning gas is less polluting than burning fossil fuels in a power plant to generate electricity. The bottom line: drying a load of laundry in a gas dryer will cost 15-25¢, compared to 31-40¢ in an electric one.
The actual technology of drying clothes varies little from one model to another, with energy savings being obtained chiefly through what the industry calls "termination controls"-in other words, controls that shut the machine off sooner than it otherwise would have. These include simple timers (which require the user to guess how long a given load will take to dry), more advanced temperature sensors (which indirectly estimate dryness), and sophisticated moisture sensors (which directly measure dryness). On average, a moisture sensor will reduce energy use by 15%-worth about $12 a year-and will be gentler on your clothes by avoiding overdrying. While temperature sensors sometimes overdry clothes, they still average 10% savings over timers.
In years to come, microwave technology may offer the first big breakthrough in dryer efficiency. Two California companies have jointly developed a prototype microwave clothes dryer that uses up to 12% less energy than conventional ones, but this model is still in the testing phase.
MISCELLANEOUS APPLIANCES
Small appliances and electronics account for 14% of the average household's total energy consumption. The table on the next page lists the average energy use of a variety of small and large appliances-and reveals that some consume much more energy than their size or importance would suggest.
Read the product literature before you buy any appliance, since the wattage demand can vary greatly between different models.
Waterbeds
A waterbed typically uses nearly as much electricity as a refrigerator, costing about $77 per year to heat. The 17 million waterbeds in this country consume the electrical output of five large power plants.
If you have a waterbed, here are some tips to reduce its energy costs:
Make the bed and cover it completely with a thick quilt. A quilted cover can halve your waterbed's heating bill. Insulate. Use one-inch foam or reflective wrap beneath and around the sides of the mattress (make sure the reflector is rated for your water heater temperature). Plug the heater into a timer and set it to turn off an hour or two before you get up and to come back on a few hours before you go to bed.
Televisions and Home Electronics
Televisions are not big energy consumers-a typical 19.5" set costs $17 a year to run, assuming average use-but nearly every household has at least one.
Most color televisions and VCRs have an instant-on feature that keeps the tubes constantly warmed up, so even when the television is turned off this feature is using up to 8 watts of electricity. According to one calculation, the electricity used by the instant-on feature of all the televisions in the U.S. drains as much electricity as the output of a Chernobyl-sized nuclear power plant! New solid-state sets take less time to warm up and so don't need the instant-on feature, but they still draw some power if for remote-control standby.
Small and "Phantom" Loads
Many appliances use electricity even when they're "off." A small amount of electricity is constantly consumed by such features as AC adapter plugs on cordless and rechargeable appliances, cable TV converter boxes, clocks on coffee makers, and so on. Even when your cordless vacuum, laptop computer, or rechargeable battery unit is fully charged, the adapter plug still draws a small amount of electricity. In a study of one typical California home, it was estimated that such "phantom" loads consume nearly 700 kWh a year, or nearly $60 worth of electricity. Unplug adapters when recharging is completed or when not in use.
Don't use batteries for electronic equipment when you can use line power instead. Electricity from disposable batteries is phenomenally expensive: it works out to $130 per kWh for D cell batteries. In comparison, electricity through the socket costs about 8¢ per kWh. It's well worth investing in AC adapters and rechargeable batteries.
For a rundown on the energy demands of home office equipment, see "Computers and Peripherals" in this Home Energy Briefs series.
Dishwashers
A dishwasher typically uses the equivalent of 700-850 kWh of electricity annually, or nearly as much energy as a clothes dryer or freezer. The majority of this energy is used not to run the machine but to heat the water for washing dishes-which means that the best way to improve dishwashing efficiency is to cut down on hot-water consumption.
Most modern dishwashers have a built-in booster heater, which raises the temperature of the water during wash cycles to 140°F to kill germs and cut grease. While this feature adds somewhat to the dishwasher's electricity demand, it enables you to lower the setting on your hot-water heater to 120°F (the highest temperature needed for all other household uses). Each 10°F reduction in your water heater's setting will save up to 13% on your total water heating bill, and also reduce the danger of scalding. But beware, many dishwasher booster heaters are not thermostatically controlled-they turn on regardless of the intake water temperature, which merely adds to the energy waste if you don't turn down your water heater. (For further tips on improving your water heater's efficiency, see the "Water Heating" brief in this series.)
The most water-efficient dishwashers currently on the market use about 5 gallons of hot water per load, or less than half as much as the least efficient ones. Remember that a dishwasher that uses half as much water will only need half as much energy to heat that water. You can also reduce your machine's water energy use manually by using "light wash" or "energy saving" cycles when appropriate.
Another energy-saving option-mandatory on all new models-is a switch that allows you to choose between heat-drying and air-drying. Heat-drying elements draw considerable electricity; circulation fans for air-drying use relatively little.
Sizing of appliances is a critical factor in achieving energy efficiency. In dishwashers, there are compact and standard-capacity units. Compact models use less energy per load, but hold fewer dishes so you may actually consume more energy operating them more frequently.
Tips:
Avoid rinsing dishes before you load them in the dishwasher, or if you must rinse, use cold water. Modern dishwashers are built to cut through most food residue, and rinsing only duplicates this effort.
Always operate a dishwasher with a full load. If this isn't possible, use an energy-saving cycle.
Select the no-heat-drying option, if your machine has it. If not, stop the machine before the drying cycle begins and
open the door to let dishes air-dry.
Hand-Washing
Hand-washing dishes can use a lot less hot water than a dishwasher, if done efficiently. It also, obviously, eliminates the cost of the dishwasher itself and the electricity to run it.
Here are some tips for efficient hand-washing:
Wash dishes by the load, not one at a time.
If you have two sinks, fill one with hot soapy wash water and the other with cold rinse water. Leaving the water running when washing or rinsing will cost you about 4¢ a minute. A 2.5-gallon-per-minute faucet aerator will save as much as half the water used by standard faucets, and it's easy to install. An aerator with a fingertip on-off valve makes it easy to shut the flow to a trickle between uses.
Refrigerators and freezers consume about a sixth of all electricity used in American homes, and much of that can be saved.
Although advances in technology have cut refrigerator energy consumption by 60% over the past twenty years, the refrigerator still uses far more electricity that any other home appliance. In just the past two years, Federal appliance standards have improved refrigerator efficiency by 20% to 25%. Even these dramatic gains can be bettered: studies and field tests have shown that manufacturers can make refrigerators that use less than one-third as much electricity as a new model meeting the 1993 appliance standards.
If you have an old model, it is probably very inefficient and could cost up to $140 a year in electricity to run (or twice that if you have high electric rates). A new, efficient one could save up to two-thirds of that electricity cost, and it may be cost-effective to replace an old clunker even before it dies a natural death.
Since all of the electricity used by your refrigerator is converted into waste heat vented out the back of the fridge, saving 1,000 kWh per year by buying a new fridge will also save you approximately $34 in air conditioning costs every year. This will reduce your payback from eight or nine years to six years.
Choosing a New Refrigerator
If you're in the market for a new refrigerator, it definitely pays to shop around for an efficient one, since there is significant variation in the energy efficiency of various models.
Carefully consider the style, size, and features you want and what the energy implications might be. The good news is that efficient models often cost less than inefficient ones, since many of the features which add to cost - such as through-the-door ice - also add to energy consumption, while those that save energy, like better insulation, also make other components smaller (compressors) or unnecessary (anti-sweat heaters).
Many electric utilities offer incentives, typically a rebate of around $100, to customers in the market for a new refrigerator. Call your utility and ask if they offer rebates.
Side-by-side refrigerator/freezers use roughly 7-13% more energy than similarly sized top-freezer models. Larger units usually consume more electricity than smaller ones but may be more efficient on the basis of kilowatt-hours per cubic foot. Too large a model wastes space and energy, but one too small might mean extra trips to the grocery store.
It is much less expensive to buy and run one big refrigerator than two small ones, assuming roughly equal efficiencies.
Automatic defrost on older fridges is an energy consumer but some new fridges use "smart" controls and a smaller heater that only operates when frost accumulates. The result is that some auto defrost models that are almost as efficient as manual defrost models.
Anti-sweat heaters boost consumption by 5 to 10 percent.
For the convenience of through-the-door water or ice dispensers you'll pay an extra $250 in the purchase price, have higher electric bills, and you may even pay more in repair bills.
Automatic ice-makers typically increase energy use by 14 to 20% and increase the price of a refrigerator by about $75.
The costliest refrigerator is the one you don't really need but run anyway - the one keeping a six-pack cold in the extra fridge in the garage. Unplug it.
Check the "Energy Guide" labels that appear on all new models and compare annual energy usage to the values listed in the above chart. This chart shows the amount of electricity used (in kWh) and the energy cost in dollars per year at an electric rate of 8.2 cents per kilowatt-hour (electric rates vary), of the most efficient refrigerator/freezers commercially available in the U.S. in 1993 in the sizes and styles indicated. A comprehensive brand-name list of the most efficient refrigerator models in all sizes and styles can be found in Consumer Guide to Home Energy Savings, by Alex Wilson and John Morrill, available in bookstores or from the American Council for an Energy-Efficient Economy, 2140 Shattuck Avenue #202, Berkeley, CA 94704; (510) 549-9914.
SERP Refrigerators
In a highly publicized contest recently sponsored by 25 U.S. utility companies, major manufacturers of refrigerators competed for a $30 million purse in the Super Efficient Refrigerator Program (SERP). The goal was to produce an energy-efficient fridge, free of chlorofluorocarbons (CFCs). CFC chemicals contribute to the destruction of the earth's ozone layer and all manufacturers will be banned from using this substance by the end of 1995. Whirlpool won the competition and is now marketing a 22 cubic foot SERP™ fridge for KitchenAid, Sears, and Gibson as well as under their own brand name. The SERP fridge will retail in the $1,200-$1,600 range while exceeding the 1993 Federal refrigerator standards for side-by-side refrigerators by almost 30% (side-by-side standards are not as stringent as those for refrigerators with the freezer on top).
There are many other energy-efficient refrigerators on the market, and the most energy-efficient brands with the freezer on top are still more efficient than Whirlpool's 1994 SERP™ side-by-side. Whirlpool has also begun selling other models and sizes of CFC-free refrigerators, and the race for efficiency continues. Manufacturers' innovations, such as vacuum insulating panels, duel evaporators, and new compressors will contribute another 10-30% in energy savings as early as 1995.
For more information on where to buy a SERP™ fridge call Whirlpool at (800) 253-1301 or the SERP organizers at (800) 927-3985. (The SERP refrigerator will only be available within the service territories of the utilities participating in the SERP program.) Contact your local utility for other opportunities for rebates on the purchase of new energy-efficient refrigerators.
Choosing a New Freezer
Consider buying a manual defrost freezer (which are more common anyway). Manual defrost freezers consume 35-40% less electricity than comparable automatic-defrost models. They'll cost you less to run, and do a better job of storing food, since auto-defrosters remove moisture and can dehydrate food, causing freezer burn. Because freezers are opened far less frequently than refrigerators, frost won't build up as quickly as it would in manual defrost refrigerators.
Chest (top-loading) freezers are 9-22% more efficient than upright (front-loading) models because they are better insulated and less warm air enters the freezer compartment when the door is opened. Study Energy Guide labels carefully. The most efficient freezers currently available use the kWh per year indicated below and cost the amount per year shown at an electric rate of 8.2 cents per kWh.
Disposing of Your old Refrigerator or Freezer
Since refrigerators contain chlorofluorocarbons (CFCs), in their refrigerant (Freon) and foam insulation, it is important to dispose of retired units in an environmentally responsible manner. Further, the other materials (metals, plastics, etc.) can be recycled to conserve resources. Contact your local utility to find out what programs exist in your area to recycle refrigerators. Unfortunately, such programs are not available in all localities, and many existing programs are not comprehensive.
For example, while about a dozen refrigerator recycling programs nationwide retrieve Freon, only one existing program (run by Northeast Utilities in Hartford, CT) also recovers CFCs from insulating foams. Since nearly 85% (approximately 2.5 lb. of the 3 lb. total) of the CFCs in a typical U.S. refrigerator is contained in the insulating foam, it is imperative that we work quickly to develop recycling programs that address this hazard. Citizens can urge their utilities and local governments to get involved in developing such programs in their area.
Greater Efficiency Through Maintenance
While it is important to not dawdle with the refrigerator door open, there are quite a few ways to help make any refrigerator operate more efficiently.
Check location: You can boost energy efficiency by making sure your refrigerator is not located in direct sunlight or next to the oven or dishwasher. Also, be sure that air can circulate freely around condenser coils by leaving a space between the refrigerator and the wall or cabinets.
Keep the fridge top uncluttered: Don't use the top of your refrigerator as an extra kitchen shelf. A cluttered fridge top can block the air-circulation needed to keep the compressor working efficiently.
Check temperature: The refrigerator should measure between 36û and 40ûF and the freezer between 0û and 5ûF. Use a thermometer to check the actual temperature, and adjust the thermostat if necessary. Your refrigerator can use 25% more energy if it is kept 10ûF colder than recommended levels.
Clean condenser coils: At least once a year, unplug the unit and brush or vacuum off the condenser coils (located on the back of the refrigerator or behind the front grill). Dust and dirt accumulation degrades performance.
Check door seals: Keep door seals or gaskets clean and in good repair. If the seals can't hold a dollar bill firmly in place, they may be ripe for replacement. Your appliance dealer can get them for you.
(This test may not work if your fridge has magnetic seals; in this case, put a bright flashlight inside the refrigerator, dim the lights in the kitchen, and check for light leakage.) New seals are not cheap, however, and this may be a good time to decide whether to buy a new efficient refrigerator.
Check "Power-Saver" switch: Many refrigerators have small heaters (yes, heaters!) in the walls to prevent condensation build-up on the outside surfaces. If you have the option to switch this feature off, do it!
Defrost as needed: If you have a manual defrost or partial automatic defrost, be sure to defrost the unit regularly.
Buildup of ice on the coils makes the compressor run longer, wasting energy.
Cover liquids and foods.
Mark packages and containers for easy identification: Scratching you head with the refrigerator door open wastes energy.
Keep cold air in: Remember to open the door as infrequently and as briefly as possible. Less cold air will spill out when you do open the door if the refrigerator or freezer is nearly full. If your freezer is almost empty, put in a few air- or water-filled plastic containers. "CHILLshield" is a system of vinyl flaps that prevents cold air from escaping when the refrigerator door is opened, saving up to 10-20% of the appliance's energy use. It is available for $25 from The
Conserve Group (PO Box 1560, Bethlehem, PA 18016-1560; 215/691-8024) and from environmental stores and catalogs.
Install an energy-saving Green Plug: This device reduces the voltage of the electricity feeding into an appliance, which reduces enegy waste. At a cost of $35-$40, a Green Plug will save 3% to 20% of your refrigerator's electricity consumption, paying for itself in 1 1/2 to 10 years. Green Plugs require some adjustment to your fridge evaportor fan louver (the dial setting in the freezer) and are most cost-effective in regions with high electricity rates and higher line voltage. They are available through hardware and department stores and home centers.
Lighting uses about a fourth of all electricity used in the United States, consuming the energy produced by 120 large powerplants (about 4/5 directly and 1/5 in extra air conditioning energy to remove unwanted heat). By using the most efficient sources of electric light in the most effective ways, and by capturing more of the daylight reaching our homes and businesses, we can profitably save up to 90% of this electricity.
Lighting Efficiency
The visible light output of a source is measured in lumens. The power consumed by that source is measured in watts. The more lumens produced per watt consumed, the more efficient the light source. The standard incandescent light bulb, used in over 90% of residential lighting, is very inefficient, producing only 10-20 lumens per watt. The incandescent light bulb is so inefficient, in fact, that about 90% of the energy it consumes is given off as heat, while only 10% is converted into light. The incandescent light bulb is really an electric space heater that happens to give off a little light. Fluorescent lighting, on the other hand, produces 30-110 lumens per watt, typically yielding three to four times the amount of light for each watt it consumes.
Compact Fluorescents
The most significant development in lighting technology for homes in the past decade has been the compact fluorescent lamp (CFL). CFLs screw into ordinary sockets, provide incandescent-like color quality, last up to thirteen times as long as standard incandescents, and use one-quarter of the electricity to operate.
Don't be turned off because CFLs are fluorescent. The drawbacks some people associate with fluorescent tubes and older CFLs are primarily related to the type of ballast used to operate them and the quality of the phosphors that produce their light. New and improved phosphors provide much better color rendition than the old type, and can give the same warm, yellow light as incandescents if you wish.
A ballast is the device that starts and regulates fluorescent lights. Electromagnetic (core-coil) ballasts often take a couple of seconds to start CFLs, and may produce some noticeable lamp flicker and audible hum. (Ballasts typically last at least four times as long as lamps; electromagnetically ballasted CFLs are available in modular units that allow the lamp to be replaced; they also tend to be a bit less expensive than electronic ones.) More advanced and user-friendly CFLs are now available with electronic ballasts that solve all of the problems associated with electromagnetic ballasts, and are also more efficient.
There are now over 500 kinds of CFLs on the U.S. market suitable for most applications except dimmers (and special models are needed for outdoors and very low temperatures). Many have globes, reflectors, or decorative diffusers.
Each incandescent bulb we replace with a CFL prevents the emission of 1,000-2,000 pounds of carbon dioxide from powerplants that leads to global warming, and 8 to 16 pounds of sulfur dioxide that causes acid rain;. One CFL also eliminates the need to produce and dispose of up to a dozen incandescent bulbs. To sweeten the deal further, each CFL you install saves you roughly $25-50 over the lifetime of the bulb. As Amory Lovins puts it, "This isn't a free lunch, it's a lunch you're paid to eat!
Life-Cycle Cost
One of the first things most people notice about CFLs is their whopping price tag-- "What? $25 for a light bulb?" This brings us to the subject of life-cycle cost. Though some CFLs are available for much less, the above figure shows how purchasing a $25 bulb can actually save you money. To get the best return on your investment, install CFLs in fixtures used at least two or three hours per day.
Written by: Rocky Mountain Institute
RELATED LINKS:
RESOURCES
American Council for an Energy-Efficient Economy, 2140 Shattuck Avenue, Suite 202, Berkeley, CA 94704 (510/549-9914). Publishes Consumer Guide to Home Energy Savings, which lists brands and models of appliances and their annual energy use and cost.
Energy Efficiency and Renewable Energy Clearinghouse, PO Box 3048, Merrifield, VA 22116 (800/523-2929). Has free information on efficient appliances.
Florida Solar Energy Center, 300 State Road 401, Cape Canaveral, FL 32920-4099 (407/783-0300). Researches appliance efficiency.
Massachusetts Audubon Society, Education Resources Office, 208 South Great Road, Lincoln, MA 01773 (617/259-9506). Publishes an appliances booklet.
Contact your local utility or energy office for information on rebates that may be available in your area on the purchase of new energy-efficient appliances.
|
|---|
| * * * COMPANIES & PRODUCTS * * * |
|---|
| * * * IN-HOUSE RESOURCES * * * |
|---|