Published February 25, 2012: Updated Monday May 2, 2016
Plug any appliance into the Kill-A-Watt meter and you will see how much energy it consumes.
Leave an appliance plugged in for a few hours/days and you will be able to see how much it is costing your to run that appliance. You will also know if that appliance is operating correctly/efficiently.
Watch this informative video on how to measure average power draw on a cycling appliance (like a refrigerator).
You need to get a Kill-A-Watt meter. Your marriage may depend on it. Really? Probably not but maybe.
Every household need at least one Kill-A-Watt meter. Maybe 2 or 3 or 4 or....
You can pick one up at any hardware store or buy them from Amazon here.
Update: The older models had a 1 watt resolution. Newer ones have a 0.1 watt resolution and are more accurate at measuring very small loads.
Right now as I type this, I am looking down at a Kill-A-Watt meter connected to my computer. My PC, monitor and desk lamp together are consuming 81 watts.
Having this type of feedback will allow me the consumer to make educated decisions about the energy efficient products that I purchase.
Example#1: The energy star refrigerator that I bought was not (by default) meeting its low power consumption claim. Without the Kill-A-Watt meter, I would have ignorantly continued through life thinking I had a super efficient fridge and not save as much money on my electric bill as I could have.
Example#2: My HP Laser printer has a fancy Energy Star power saving mode. Using the Kill-A-Watt meter, I can clearly see that it isn't always entering this mode like it should and it is unnecessarily
remaining in a higher power state.
Example#3: I have a fairly new PC. Doing nothing other than swapping out its factory original ATX power supply with an 80+ certified supply, I can see by the Kill-A-Watt meter reading that my PC now draws 29 watts less power than it did before, yet the PC performance is exactly the same.
According to the Kill-A-Watt meter, my $19 CD player from Walmart
draws 8 watts all the time, even when it is switched off.
I can now make an educated decision whether it is worth the additional hassle to unplug this appliance when not in use.
According to the Kill-A-Watt meter, my cell phone charger draws
essentially no power at all when plugged in (but not charging). I
can now make an educated decision to not worry about it because it
will not cost me a dime even after 1 year of leaving this device
I am now looking at my clock and it reads 12:19AM. According to the Kill-A-Watt meter, I need to be at work at 06:00 tomorrow morning. Correction.. At 06:00 this morning. Good night, er morning.