Monitor Energy Usage

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What is a Kill A Watt Monitor?

Kill A Watt MeterA 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 us at (503) 397-1844 for more information.