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  • Home > Ways to Save > At Home > Efficiency Tips > Monitor Energy Usage

    Monitor Energy Usage

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    What is a Kill A Watt Monitor?

    Photo of Kill A Watt MonitorA Kill A Watt Monitor is a device that measures the electrical usage of small plug-in appliances and other devices. You can use a Kill A Watt Monitor to learn which devices use the most energy, and to find devices that use energy when they are turned off (called “phantom” loads).

    Kill A Watt Monitors are available for check-out from local libraries, or can be purchased at electronics stores. We also have a limited supply of monitors available for check-out from our office.

    What You Can Measure

    The Kill A Watt Monitor can be used to measure the electrical consumption of 120-volt household electronics up to 1875 watts. 220-volt appliances, such as ovens or clothes dryers, cannot be measured with a Kill A Watt Monitor. 

    Here are some items you might measure:

    • Cable or Sattelite Box
    • Television
    • VCR/DVD or Blue-Ray Player
    • Stereo Equipment
    • Gaming System
    • Computer Printer
    • Scanner/Fax
    • Refrigerator
    • Freezer
    • Microwave
    • Toaster
    • Coffee Maker
    • Window A/C Unit
    • Cordless Phone
    • Space Heater (1,875 watt max)
    • Hair Dryer
    • Aquarium
    • Cell Phone Charger
    • Fountain Pump

    How to Use It

    1. Plug In the Kill A Watt, Then Plug In the Device

    Plug the Kill a Watt Monitor into an electrical socket, power strip, or extension cord, and then plug the device you want to measure into the Kill a Watt Monitor. Turn the device on. The voltage will appear on the display. It should read approximately 120V. 

    2. For an Instant Reading, Press the “Watt/VA” Button

    For an instant reading of the number of watts being used by the device, press the “Watt/VA” Button. You can take readings on several different devices to compare the energy they draw. A lamp with a 60-watt standard incandescent light bulb will draw about 60 watts. A lamp with an equiavelent compact fluorescent light bulb will draw about 15 watts.

    3. Turn off the Electrical Device to Check for Phantom Loads

    The Kill A Watt can be used to identify phantom loads. Just turn the electrical device that is plugged in to the Kill A Watt Monitor off and then check the “Watt/VA” reading again to see whether the device draws power when it’s off. Some common sources of phantom loads are devices with built-in clocks, such as coffee makers, or instant-on capabilities, such as cable TV boxes. Also, devices with remote control capability or battery chargers draw power continuously. 

    4. For a More Accurate Reading, Wait an Hour or More

    The Kill A Watt Monitor will continuously measure the power used by a device from the moment the device is plugged in until you unplug it. To get a good average reading, leave devices plugged in for one hour, then press the “KWH/Hour” button to see the total energy consumed. Items that cycle on and off, such as refrigerators, should be plugged in for several hours or overnight. To re-set the Kill A Watt Monitor to measure a new device, unplug the Kill A Watt Monitor and and plug it back in.

    Local Libraries with Kill A Watt Monitors

    Kill A Watt Monitors are available for check out from these local libraries:

    St. Helens Public Library
    375 South 18th Street
    St. Helens, OR
    (503) 397-4544

    Scappoose Public Library District
    52469 SE 2nd Street
    Scappoose, OR
    (503) 543-7123

    Columbia City Community Library
    205 I Street
    Columbia City, OR
    (503) 366-8020

    City of Rainier Library
    106 B Street
    Rainier, OR
    (503) 556-7301

    Borrow a Kill A Watt Monitor from Our Office

    We also stock a few Kill A Watt Monitors, and a different style of monitor with a longer cord that is useful for measuring the energy use of refrigerators or for customers who might have difficulty bending down to read a Kill A Watt Monitor. Contact our Energy Experts at (503) 366-5470 or for more information.