Appliances account for about 13% of your household’s energy costs, with Water Heater, Refrigeration, and Laundry at the Top of the list.
When you’re shopping for appliances, think of two price tags. The first one covers the purchase price, think of it as a down payment. The second price tag is the cost of operating the appliance during its lifetime. You’ll be paying on that second price tag every month with your utility bill for the next 10 to 15 years, depending on the appliance. (Refrigerators last an average of 12 years; clothes washers about 11 years; dishwashers about 10 years; water heaters about 9 years)
When you shop for a new appliance, look for the ENERGY STAR label. ENERGY STAR products usually exceed minimum federal standards by a substantial amount. We highly recommend that you find a home with ENERGYSTAR labeled appliances compared to standard models, ENERGY STAR-qualified refrigerators use 20% less energy and ENERGY STAR-qualified dishwashers use 10% less energy and 18% less water!
Water Heaters are some of the most costly electricity consuming appliances as shown in the chart below:
This chart shows how much energy a typical appliance uses per year and its corresponding cost based on national averages. For example, a refrigerator uses almost five times the electricity as the average television uses. Source; Buildings Energy Data Book 2010.2.1.16 Operating Characteristics of Electric Appliances m the Residential Sector
Water heating can be the largest energy expense in your home. It typically accounts for about 18% of your utility bill.
There are four ways to cut your water heating bills: use less hot water, turn down the thermostat on your water heater, insulate your water heater, or buy a new, more efficient model.
Design of water-heating systems is based on three interrelated factors: Recovery Capacity (gallons per hour), Energy Input (BTUs per hour), and Storage Capacity (gallons). These are determined by occupancy, number of plumbing fixtures, and per capita use.
Fuels for water heating include: fossil fuel, electricity, solar energy, and waste heat recovery. Each of these fuels can be used directly or indirectly. Direct water heating applies the fuels heat to only one heat exchanger—a tank or pipes containing domestic hot water. Indirect water heating applies heat collected by water or air in a remote area to heat the domestic hot water. This remote heat comes from a boiler, solar collector, or waste heat exchanger. Indirect water heaters employ two or more heat exchangers.
Most single-family homes use direct storage water heaters that combine the heating device, heat exchanger, and storage tank into one unit. Single-family, storage water heaters hold 20 to 90 gallons of water. Their tanks are insulated with fiberglass or plastic foam insulation and covered with outer jackets of painted sheet metal. Hot water exits the top of the tank, and cold water enters through a tube extending to the tanks bottom.
Older storage water heaters, insulated with fiberglass, have a thermal resistance (R-value) of R-3 to R-6, while newer models have R-7 to R-25. The extra cost of the better insulated water heaters will be returned to the buyer in energy savings in a year or less. Improved insulation is the only significant, recent improvement to electric storage water heaters.
A thin layer of glass, mineral, or plastic coats the steel tanks inside for corrosion resistance. A metal rod attached to the top of the tank, called the sacrificial anode, also protects the tanks steel parts from corrosion.
Traditional Gas Storage Tank Water Heaters are about 75% thermally efficient. Energy Star High Efficiency water heaters are up to 96% thermally efficient. This means nearly all the heat they generate gets transferred to directly to the water. A thermally efficient water heater will cut back on heat loss and your utility bills.
Electric water heaters have lower standby losses and higher energy factors than similar gas, propane, and oil water heaters because they don’t have flue pipes running up the center of their tanks like combustion units do. However, electric water heating is typically 1.5 to 2 times more expensive than natural gas, reflecting electricity’s generation and distribution losses. Because of the higher cost of electricity, electric water heaters tend to have thicker insulation—3 inches of plastic foam in the best new models.
Electric water heaters don’t need a chimney, so they can be easier to install than gas water heaters. However, since electricity is more expensive than gas, propane, or oil, many people choose combustion water heaters over electric.
Electric storage water heaters have higher energy factors and lower recovery capacities than fuel-fired water heaters. They tend to have higher storage capacities to compensate for their slower recovery.
Tankless water heaters do not store hot water, unlike conventional North American water heaters. In tank less (also known as “demand” or “instantaneous”) water heaters, a gas burner or electric element heats water only when there is a demand (or hot water. Hot water never runs out but the flow rate (gallons of hot water per minute) is limited. Eliminating standby losses from the tank reduces energy waste. Before rushing out to buy a demand water heater, be aware that they are not appropriate for every situation. Here are some of the factors to consider.
Consider your water distribution system. If the hot water uses in your home are relatively close together, with short hot water lines between them, a tankless system may work well for you. In many U.S. homes, water uses are widely spaced at opposite ends of the house. If this is the case in your home, a single tankless system with long distances between the system and the point-of-use can increase frustration, because each time you turn off the water, the next time you use the water again it will restart with a “slug” of cold water.
Tankless heaters are more expensive than conventional water heaters. The largest of them provides about 5 gallons of hot water per minute at 140°F. Taking a hot shower and running the automatic dishwasher at the same time stretches a tankless water heater to its limit.
Solar water heaters are classified as active or passive depending on whether they use a pump to circulate water. Batch solar water heaters are just a black painted tank inside a partially glazed and partially reflective box. Thermosiphoning solar water heaters are also passive solar water heaters. They move water from the collector to a storage tank on top of the collector using only the buoyancy of hot water.
If you heat water with electricity, have high electric rates, and have an unshaded, south-facing location (such as a roof) on your property, consider installing a solar water heater. The solar units are environmentally friendly and you can have them installed on your roof to blend with the architecture of your house.
Solar water heating systems are also good for the environment. Solar water heaters avoid the greenhouse gas emissions associated with electricity production. When shopping for a solar water heater, look for the ENERGY STAR label.
Conserve Water- Your biggest opportunity for savings is to use less hot water. In addition to saving energy (and money), cutting down on hot water use helps conserve dwindling water supplies, which in some parts of the country is a critical problem. A family of four each showering five minutes a day can use about 700 gallons per week—a three-year drinking water supply for one person. Water-conserving showerheads and faucet aerators can cut hot water use in half. That family of four can save 14,000 gallons of water a year and the energy required to heat it.
Insulate Your Existing Water Heater- If your electric water heater was installed before 2004, installing an insulating jacket is one of the most effective do-it-yourself energy-saving projects, especially if your water heater is in an unheated space. The insulating jacket will reduce standby heat loss—heat lost through the walls of the tank—by 25-40%, saving 4-9% on your water heating bills.
Insulate Hot Water Pipes– Insulating your hot water pipes will reduce losses as the hot water is flowing to your faucet and. more importantly, it will reduce standby losses when the tap is turned off and then back on within an hour or so. A great deal of energy and water is wasted waiting for the hot water to reach the tap. Even when pipes are insulated, the water in the pipes will eventually cool, but it stays warmer much longer than it would if the pipes weren’t insulated. Insulated pipes deliver water 2 degrees to 4 degrees Hotter than uninsulated pipes, allowing for a lower tank temperature setting.
Lower the Water Heater Temperature- Keep your water heater thermostat set at the lowest temperature that provides you with sufficient hot water. For most households, 120°F water is fine (about midway between the low” and “medium” setting). Each 10°F reduction in water temperature will generally save 3-5% on your water heating costs. When you are going away on vacation, you can turn the thermostat down to the lowest possible setting, or turn the water heater off altogether for additional savings. With a gas water heater, make sure you know how to relight the pilot if you’re going to turn it off while away.
Install aerating, low-flow faucets and showerheads.
Repair leaky faucets promptly; a leaky faucet wastes gallons of water in a short period of time.
Install heat traps on the hot and cold pipes at the water heater to prevent heat loss. Most new water heaters have built-in heat traps.
Refrigerators are large energy consumers, accounting for 9% to 15% of households total energy consumption. A refrigerator runs day and night, 365 days a year.
A refrigerator uses almost five times the electricity as the average television uses.
A new refrigerator with an ENERGY STAR label uses at least 20% less energy than required by current federal standards and 40% less energy than the conventional models sold in 2001.
Models with top-mounted freezers use 10%-25% less energy than side-by-side or bottom-mount units
The Energy Guide label on new refrigerators tells you how much electricity in kilowatt-hours (kWh) a particular model uses in one year. The smaller the number, the less energy the refrigerator uses and the less it will cost you to operate. In addition to the Energy Guide label, don’t forget to look for the Energy Star label.
Don’t keep your refrigerator or freezer too cold. Recommended temperatures are 37°-40°F for the fresh food compartment and 5°F for the freezer section. If you have a separate freezer for long-term storage, it should be kept at 0°F.
Make sure your refrigerator door seals are airtight. Test them by closing the door over a piece of paper or a dollar bill so it is half in and half out of the refrigerator. If you can pull the paper or bill out easily, the latch may need adjustment, the seal may need replacing, or you may consider buying a new unit.
Cover liquids and wrap foods stored in the refrigerator. Uncovered foods release moisture and make the compressor work harder.
Regularly defrost manual-defrost freezers and refrigerators; frost buildup decreases the energy efficiency of the unit. Don’t allow frost to build up more than one-quarter of an inch.
The efficiency of clothes washers in using water and energy has increased by a factor of five during the past 20 years. Horizontal-axis (front loading) clothes washers use far less energy and water than vertical axis (top loading) machines. In fact, horizontal-axis machines save 50-75% of both energy and water, compared to most vertical-axis models. Wash clothes in cold water, 90% of the Energy used in clothes washers goes to water heating.
Gas clothes dryers operate more economically than electric clothes dryers. At the average price for electricity and gas, electric clothes drying costs 30-40 cents per load, versus gas at 15-20 cents per load.
Temperature-sensing or humidity-sensing dryer controls may save 5-15% over timed drying. When working correctly, these controls prevent over-drying. Controls that sense humidity are the most efficient.
Cleaning the dryer lint filter after each cycle minimizes drying time. Over time lint collects in the vent, elements, and air passageways reducing airflow and increasing cycle time. Every few years, a dryer and its vent should be thoroughly cleaned.
For obvious reasons, line-drying is the most cost effective way to save energy on clothes drying.
There are two ways to reduce the amount of energy used for washing clothes—use less water and use cooler water. Unless you’re dealing with oily stains, the warm or cold water setting on your machine will generally do a good job of cleaning your clothes. Switching your temperature setting from hot to warm can cut a laundry load’s energy use in half!
Look for the ENERGY STAR and Energy Guide labels. ENERGY STAR clothes washers clean clothes using 50% less water and 37% less energy than standard washers.
Wash and dry full loads. If you are washing a small load, use the appropriate water-level setting.
When shopping for a new clothes dryer, look for one with a moisture sensor that automatically shuts off the machine when your clothes are dry. Not only will this save energy, it will save the wear and tear on your clothes caused by over-drying.
Clean the lint screen in the dryer after every load to improve air circulation and prevent fire hazards.
Periodically, use the long nozzle tip on your vacuum cleaner to remove the lint that collects below the lint screen in the lint screen slot of your clothes dryer.
Use the cool-down cycle to allow the clothes to finish drying with the heat remaining in the dryer. • Periodically inspect your dryer vent to ensure it is not blocked. This will save energy and may prevent a fire. Manufacturers recommend using rigid venting material—not plastic vents that may collapse and cause blockages.
Consider air-drying clothes on clothes lines or drying racks. Air drying is recommended by some clothing manufacturers for certain fabrics.
** “ENERGY STAR” does not label Clothes Dryers because most of them use similar amounts of energy. **
More than 60 percent of American kitchens have a dishwasher, and 93 percent of newly built homes include them. According to the Consortium for Energy Efficiency, dishwashers account for 2.5 percent of the energy used in a typical household.
Most of the energy (80% to 90%) used by dishwashers is actually consumed by the water heater. Your dishwasher may dictate the temperature setting of the water heater. Many older dishwashers require a water supply of at least 130°F to get dishes clean. Most newer dishwashers have a small water heater to boost water temperature to about MOT. This saves water heating energy by reducing the required water temperature and standby losses of the water heater.
Like clothes washers, dishwashers conserve energy and water when using their low and medium cycles. Water usage varies from a low of 7 gallons to a high of 14 gallons per wash, from the light wash cycle to the heavy one.
The Traditional, Built-in, Under-the-Counter Dishwasher – This style is permanently plumbed into your home’s water and plumbing system. Standard width is 24 inches. ENERGY STAR estimates a “standard” dishwasher has “a capacity greater than or equal to eight place settings and six serving pieces.”
Compact Built-in, Under-the-Counter Dishwashers – ENERGY STAR defines a compact dishwasher as one “being able to fit less than eight place settings and six serving pieces.” These are usually 18 inches wide, designed for tight spaces and small kitchens.
Portable Dishwashers – Portable dishwashers come in both standard and compact sizes, are mounted on wheels, have finished sides, usually feature butcher-block tops and come with water hookups to attach to your sink faucet. They drain into your sink. They offer an option when cabinet space in your kitchen is at a premium and a standard dishwasher cannot be installed. Portables can be rolled into a closet or across the room when not in use. They offer an easy option for renters who want a dishwasher but can’t remodel a kitchen that doesn’t have one.
Countertop Portables – A variation on the roll-around dishwasher, these models, roughly the size of a microwave oven, sit on a counter. Most units are no more than 17 inches tall and fit between the counter and any overhead cabinets. They provide a good choice for apartments, office kitchens or tiny kitchens. When in use, they are temporarily connected to the faucet and they drain into the sink. Some models claim to hold as many as six normal-sized place settings.
• Check the manual that came with your dishwasher for the manufacturer’s recommendations on water temperature; many have internal heating elements that allow you to set the water heater in your home to a lower temperature (120°F).
• Scrape, don’t rinse, off large food pieces. Soaking or pre-washing is generally only recommended in cases of burned- or dried-on food.
• Be sure your dishwasher is full (not overloaded) when you run it.
• Avoid using the “rinse hold” on your machine for just a few soiled dishes. It uses 3-7 gallons of hot water each use.
New ovens and stovetops – also called kitchen stoves and ranges – have no federal energy regulations, so they don’t carry EnergyGuide labels or ENERGY STAR recommendations.
These kitchen appliances can be powered by either natural gas or electricity. Electric ovens are usually less expensive to purchase, but since gas is typically less expensive than electricity, gas ovens usually cost less to operate.
Some cooks prefer the temperature control that cooking with gas gives. If you cook a lot, consider that a modern gas stove with an electronic ignition can cost half as much to operate as a standard electric stove. (Electronic ignition does away with the pilot light, reducing gas use by approximately 30 percent.)
The energy efficiency of gas-burning cooktops with electronic ignition doesn’t vary much. Electric cooktops, however, offer several energy efficiency options. The more efficient ones are initially more expensive, and may not be cost-effective unless you cook often.
In addition to the standard electric coil elements, there are a number of new types of electric burners on the market: solid disk elements, radiant elements under glass, halogen elements, and induction elements.
Solid disk elements and radiant elements are mounted under glass, making them easy to clean, but they take longer to heat up and use more electricity, compared to electric coils.
Halogen cooktops use powerful bulbs filled with a halogen gas like bromine or iodine to create radiant heat under a ceramic glass surface to heat food. The food cooks because of radiation from the bulb itself and conduction between the ceramic cooktop and the pot. This uses less electricity than a standard coil element, but only if you have very flat pans that maintain good contact with the burner. Otherwise, you’ll lose heat. Since the cooking surface is smooth glass, it is easy to clean, making halogen cooking a popular choice.
Induction elements are the most energy efficient technology, using 90 percent of its energy for cooking. (By comparison, a gas burner typically uses 55 percent, while a standard electric range uses 65 percent.) Induction elements use electromagnetic waves to turn the bottom of the pot into an active heating surface. They provide accurate temperature control while keeping the smooth cooktop surface cool. An induction element can boil water up to 50 percent faster than a regular stove.
Turn off your electric burners several minutes before the allotted cooking time is up. The heating element will stay hot long enough to finish the cooking without using more electricity – a principle that works with oven cooking, too.
Make sure your stovetop electric coils work properly. A worn-out element is a real power drain.
Keep stovetop burners and reflectors clean to reflect the heat better and save energy.
Use a moderate flame setting to conserve gas.
Remember that a blue flame means your gas stove is operating efficiently. A yellowish flame indicates an adjustment is needed.
Ovens typically last for two decades, so when you buy one you’ll have to live with your energy efficiency decision for a long time. In addition to the choice of electricity or gas, consider these oven variations:
Self-cleaning ovens have more insulation than a standard oven, so it will keep the heat in better and use less energy. During the cleaning process, the oven door locks to prevent it from being opened as the oven heats up to 900 degrees Fahrenheit. This extreme temperature burns off food spilled inside the oven, leaving ash that can easily be wiped out. Self-cleaning ovens often cost more than standard ovens, but over time the energy and cost savings are well worth it.
Convection ovens continually use a fan to circulate heated air around the food being cooked. By distributing heat more evenly than ordinary ovens, convection ovens allow you to reduce cooking time and cooking temperatures and to cut energy use by about a third. Convection cooking can eliminate hot and cool spots for more even cooking. A turkey roasted in a convection oven, for example, will brown all over, rather than just on top. Convection ovens allow you to choose between conventional baking and roasting or convection baking and roasting.
Do not open the oven door often to check your food. Each time you open the door the oven temperature drops by 25 degrees. Watch the clock or use a timer instead.
Preheating your oven uses extra energy and in most cases is not necessary unless you’re baking breads or pastries. Preheat only when necessary, and then keep the preheating time to a minimum. If you are roasting a turkey or making a casserole, you can simply set the temperature according to the instructions and begin cooking your meal.
If at all possible, install your range away from your refrigerator. Heat from the range will make the refrigerator work harder and raise your electricity bill. If you do have to put the appliances next to each other, place a sheet of foam insulation between them.
Self-cleaning ovens have additional insulation and tighter-fitting oven door gaskets and hinges that make them more energy efficient. Buying one will likely save you money. Use the self-cleaning option after cooking a meal to take advantage of the oven’s residual heat and use less energy. But use the feature sparingly – if you use self-cleaning more than once a month, you will end up using more energy than you will save from the extra insulation.
Convection ovens are efficient because they continuously circulate heat, letting you decrease the cooking time and temperature. That’s why covering the racks of your oven with aluminum foil to prevent spills is a bad idea – it blocks the flow of hot air. It’s also a good idea to stagger pans on upper and lower racks to improve airflow. Cooking multiple dishes in the same oven is more efficient.
Use your broiler. It requires no preheating, so using it can save you money.
Occasionally check the seal on your oven door for cracks or tears. Even a small tear or gap can allow heat to escape. In addition, a clean seal will retain heat more effectively.
Use correct cookware. Pots with flat bottoms, straight sides and tight-fitting lids allow food to heat more quickly and cook more efficiently on the stovetop. In the oven, using glass or ceramic pans instead of metal will allow you to turn down the temperature about 25ºF and cook foods just as quickly.
Place the faucet lever on the kitchen sink in the cold position when using small amounts of water; placing the lever in the hot position draws hot water even though it may never reach the faucet.
Look for a natural gas oven or range with an automatic, electric ignition system, which saves gas since a pilot light is not burning continuously.
Look for blue flames in natural gas appliances; yellow flames indicate the gas is burning inefficiently and an adjustment may be needed. If you see yellow flames, consult the manufacturer or your local utility.
Keep range-top burners and reflectors clean; they will reflect the heat better, and you will save energy.
Use small electric pans, toaster ovens, or convection ovens for smaller meals rather than your large stove or oven. A toaster or convection oven uses one-third to one-half as much energy as a full-sized oven.
Some manufacturers are now offering “smart” appliances—appliances that can be connected to smart electric meters or home energy management systems to help you shift your electricity use to off-peak hours. Air conditioners, refrigerators, dishwashers, and other appliances may be available as smart appliances. Smart appliances don’t just turn off during times of peak electricity demand—instead, they use subtle ways to shift energy use. You might not even be aware of it. For example, your air conditioner may run slightly less often. Or your refrigerator might delay it’s defrost cycle until the middle of the night. If your utility charges lower rates for electricity at night, also called time-based rates, you could save on your utility bill.
Many appliances continue to draw a small amount of stand-by power when they are switched “off.” These “phantom loads” occur in most appliances that use electricity, such as VCRs, televisions, stereos, computers, and kitchen appliances. Most phantom loads will increase the appliance’s energy consumption a few watt-hours. These loads can be avoided by unplugging the appliance or using a power strip and using the switch on the power strip to cut all power to the appliance.
Unplug electronics and battery chargers when not in use. Combined, these small items can use as much power as your refrigerator.
Enable “power management” on all computers and turn them off or sleep mode at night. Laptops use up to 90% less energy than desktop models.
Use Power Strips: A lot of energy is wasted through electronics left plugged in, and the resulting vampire energy. Put a stop to it by using one of a number of cool, smart energy strips, which will turn off vampire energy when the electronics are not in use.
You can usually find the wattage of most appliances stamped on the bottom or back of the appliance, or on its nameplate. The wattage listed is the maximum power drawn by the appliance. Since many appliances have a range of settings (for example, the volume on a radio), the actual amount of power consumed depends on the setting used at any one time.
If the wattage is not listed on the appliance, you can still estimate it by finding the current draw (in amperes) and multiplying that by the voltage used by the appliance. Most appliances in the United States use 120 volts. Larger appliances, such as clothes dryers and electric cooktops, use 240 volts. The amperes might be stamped on the unit in place of the wattage.
Multiply the annual consumption in kWh per year (that you calculated above) by your local utility’s rate per kWh consumed to calculate the annual cost to run an appliance. Note: To estimate the number of hours that a refrigerator actually operates at its maximum wattage, divide the total time the refrigerator is plugged in by three. Refrigerators, although turned “on” all the time, actually cycle on and off as needed to maintain interior temperatures.
(200 Watts × 4 hours/day × 120 days/year) ÷ 1000
= 96 kWh × 11 cents/kWh
Personal Computer and Monitor:
[(120 Watts + 150 Watts) × 4 hours/day × 365 days/year] ÷ 1000
= 394 kWh × 11 cents/kWh
Here are some examples of the range of nameplate wattages for various household appliances:
The ENERGY STAR logo is on all qualified products that meet specific standards for energy efficiency. ENERGY STAR-qualified products exceed the federal minimum standards for efficiency and quality—sometimes significantly. Look for the label on appliances, electronics, water heaters, windows, and other products that consume energy in your home.
To help you figure out whether an appliance is energy efficient, the federal government requires most appliances to display the bright yellow and black Energy Guide label. Although these labels will not show you which appliance is the most efficient on the market, they will show you the annual energy consumption and operating cost for each appliance so you can compare them yourself.
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