## Energy Use of Some Typical Home Appliances

If you want a general estimate of how much electricity your home appliances consume, you can refer to the table at the end of this section. This table gives the energy consumption of typical home appliances. If you have appliances that are not listed in the table, or desire a more exact figure based on your household's actual energy consumption, use the formula below to estimate the amount of energy each appliance consumes:
 Wattage X Hours Used Per Day----------------------------------- 1,000 = daily kilowatt-hour (kWh) consumption(1 kilowatt = 1,000 Watts)
Multiply this by the number of days you use the appliance during the year for the annual consumption. You can then calculate the annual cost to run an appliance by multiplying the kWh per year by your local utility's rate per kWh consumed.

For example:

• Window fan: 200 Watts x 4 hours/day, 120 days/year = 96 kWh x 8.5 Cents/kWh = \$8.16 /year.
• Clothes dryer: 5,000 Watts x 2 hours/day, 48 days/year = 480 kWh x 8.5 Cents/kWh = \$40.80/year.

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.

Refrigerators, although turned "on" all the time, actually cycle on and off at a rate that depends on a number of factors. These factors include how well it is insulated, room temperature, freezer temperature, how often the door is opened, if the coils are clean, if it is defrosted regularly, and the condition of the door seals. To get an approximate figure for the number of hours that a refrigerator actually operates at its maximum wattage, divide the total time the refrigerator is plugged in by three.

If the wattage is not listed on the appliance, you can still estimate it by finding the current draw (in amps) and multiplying that by the voltage used by the appliance. (Most appliances in the United States use 120 volts. Larger appliances-clothes dryers, electric cooktops-use 240 volts.) The amps might be stamped on the unit in place of the wattage. If not, find a clamp-on ammeter-an electrician's tool that clamps around one of the two wires on the appliance-to measure the current flowing through it. You can obtain this type of ammeter in stores that sell electrical and electronic equipment. Take a reading while the device is running; this is the actual amount of current being used at that instant.

Note: When measuring the current drawn by a motor, in the first second that the motor starts, the meter will show about three times the current than when it is running smoothly. Contact EREC if you would like to know more about this.

The following are typical annual kWh consumption levels for some appliances. To determine your annual cost of operating one of these appliances, multiply the kWh/year on the table by your electric rate. The running time and wattage in this table are estimates. Your actual consumption will probably vary. Also note that many appliances continue to draw power when they are switched off. These "phantom loads," occur in most appliances that use electricity, such as VCRs, televisions, computers, and kitchen appliances. Most phantom loads will increase the appliance's energy consumption a few watts.

Appliance Time in use kWh / year
Aquarium 24 hours / day 700
Iron 1 hour/week 52
Clock radio 24 hours / day 44
Microwave oven 2.hours/week 89
Coffee maker 30 minute / day 128
Radio (stereo) 2 hours / day 73
Clothes washer
(does not include hot water)
2 hours / Week 31
Refrigerator
(frostfree 16 cubic feet)
24 hours / day 642
Dishwasher
(does not include hot water)
1 hour / day 432
Refrigerator
(frostfree 18 cubic feet)
24 hours / day 683
Dehumidifier 12 hours / day 700
Television (color) 4 hours / day 292
Electric blanket 8 hrs / day,120days / yr 175
Toaster oven 1 hour / day 73
Fan (window) 4 hrs / day,180days / yr 144
VCR 4 hours / day 30
Fan (furnace) 12 hrs / day,120 days / yr 432
Vacuum cleaner 1 hour / week 38
Fan (whole house) 4hrs / day, 120 days / yr 270
Water heater (40 gallon) 2 hrs / day 2190
Hair dryer 15 minutes / day 100
Water pump (deep well) 2 hrs / day 730
Heater (portable) 3 hours / day,120 days / yr 540
Water bed (no cover) 12 hrs / day,180 days / yr 620

Your interest in energy efficiency and renewable energy is greatly appreciated. If we can be of further assistance, please feel free to contact us again.

EREC is operated by NCI Information Systems, Inc. for the National Renewable Energy Laboratory/U.S. Department of Energy. The statements contained herein are based on information known to EREC at the time of printing. No recommendations or endorsement of any product or service is implied if mentioned by EREC.

Energy Efficiency and Renewable Energy Clearinghouse (EREC)
P.O. Box 3048 Merrifield, VA 22116
Voice: 1-800-DOE-EREC
E-mail: doe.erec@nciinc.com

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