Do Electricity Monitors Like The "Kill A Watt" Really Work?
If you're concerned about your electricity use you may have considered getting one of those energy monitoring devices like the "Kill a Watt" or the "Watts Up." But do they really work?
Our sister-publication Consumer Reports tested them to see if they were accurate.
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Comments:
What about equipment that "forgets" when it's unplugged? What's MY TIME worth reprogramming these things every time I want to save 1/15th of a cent?
As a journalism website, is it too much to ask that Consumerist actually summarize the article (or video) that is being linked to? Like "Yes, these devices are accurate. See the video for even more energy saving tips."
What about the meters' performance on low-power devices? I'm more interested in how accurately those boxes can debunk the increasingly popular conviction that little DC power supplies like cell phone and laptop power supplies can waste a lot of energy even when they aren't plugged into their respective gadgets.
Also, in what regional dialect is 'electricity' pronounced 'electrizity'?
Well, that video was kind of useless. "They both work." WOW!! How accurate are they within a certain tolerance? "Watt" is the power consumed by some of those small electrics and electronics they were talking about, especially in the power-off modes? Gods, that was a lousy video.
What is the point of this post? neither comsumerist or CR actually helps you come to any conclusion regarding these products. Only that they do what they say they do under certain tolerances.
A ploy to push traffic over to CR? Maybe.
While it may save energy, I'm never unplugging my TV and all the electronic equipment that goes with it, until they start making it with memory that saves my time and preferences when the power is off.
@Joe Lachiana: You don't have to unplug anything. Just unplugging things like my phone charger, hairdryer, TV, blender and charging hand vacuum has made a significant dent in my electricity bill.
@notlazyjustdontcare:
I have the kill-a-watt meter and tested my Motorola charger for a week without being plugged in and it was almost nothing. Now I don't waste time constantly unplugging it.
It was interesting to see the difference that my three 1500W ceramic heaters used in electricity, low was from 400W-1200W, high from 700W-1500W.
These kill-a-watt devices are great if you are measuring the power usage of various electronic devices in a commercial setting. I've always found them to be effective.
Most 'modern' TVs which meet the latest Energy Star standards aren't going to use more than a few watts when off. And if end users are total idiots and take this advice while they have a DVR you are asking for a whole host of problems.
A computer itself uses around 100 watts while on. So turning it off is basically like turning off a lightbulb. Just make sure you are completely shutdown before you do it.
@EE2000:
Clarity: Without it being plugged into a cell phone (aka not drawing a charge), but plugged into the meter.
@DeltaTee: Consumerist is owned by Consumer Reports. Thus they have some incentive to actually have you watch the video instead of summarizing it. (Of course, the whole thing could have been done as a text article to begin with!)
I have a Kill-a-Watt. It's pretty accurate--when I plugged in a 60-watt lamp, the reading was consistently at 59-60 watts. It's a neat tool for measuring how much power a device draws at idle and when it's being used. Will it ever save me the $30 I paid for it? Probably not, but I'm a nerd, and I like to know how much power my stuff draws.
I've been using my Kill-A-Watt around the office here to see if setting up wake-on-lan and having idle systems sleep is worthwhile (it is), but one of the things I have discovered is that the modern desktops and LCD monitors use almost no power in sleep mode -- actually turning them off or unplugging them is pretty pointless (a few pennies per month).
@notlazyjustdontcare: They work for that, but keep in mind the minimum reading on the Kill-A-Watt is 1 watt.
A quicker way to check is to leave the charger plugged in for a while, but not plugged into the device, and then feel it. If it's not warm to the touch, it's not wasting power.
Andrea (shown at the end of the video) needs to become more conscious of not pulling plugs out of sockets by their cords or she's going to become conscious of a nice electrical fire someday.
@segfault: What is the maximimum that Kill-a-watt can measure? My computer has a 700 watt power supply, and I'm curious how much of that is actually being drawn.
@calquist: A hair dryer or blender is not going to use electricity when it is plugged in and turned off.
Unless there is a clock on it, or other solid-state circuitry, 99% of
toasters
washing machines
dryers
hair dryers
blenders
can openers
can be left plugged in, with zero energy loss.
Sam: Lol! The brought back so many memories of my mom always hounding me to stop unplugging things by their cords. Of course being the good daughter that I am, I did it just to annoy her.
@sburnap42: They mean use a power strip to turn the power off to the devices that have a small power drain even with off.
Here's a question: How much power does the Kill-A-Watt use?
@calquist:
My TV needs to be reset to get the right signal when it's been unplugged. And all modified settings have to be changed. So ya, no thanks.
I bought one a few months ago to check on the power consumption of some of my devices in "standby" mode, including my computer, monitor, PS/3, WII and a few other things, as well as checking the power consumption of my refrigerator, freezer (etc.) to see what they're REALLY costing me on a daily basis (vs. what the little yellow "fact sheets" SAY they consume), and it did give show me indeed how much power each of my devices consumed..
Such as it costs me (at my current electricity rates) around $15 a month to keep my computer on 24/7 (more if I don't turn off the monitor), and the PS/3 -- well, we don't even want to go there. Suffice it to say I keep that sucker completely unplugged unless I'm actively using it now. :P
@ the haters - the point of this article is to make you aware that these products exist, are accurate, and can help you reduce your energy consumption. It's a much more worthwhile article than the typical complaints about isolated incidents involving individual customers.
We have several Kill-A-Watts at work.
We used them to caculate the cost of running our server room with some now power-hungry machines. I got two for about $30 off of eBay. It turns out that even we replaced the systems with much more power-friendly units, it would take about 10 years to recoup the money spent on the new systems in power savings. That's not including the time it would take to transfer/migrate/setup the new systems.
Additionally, the old systems would have to be disposed of, creating a whole other level of waste so we decided to keep each one until it fails (yes, tons of automated backups.)
So they're useful for not just saving power, but assessing where those savings are best put to us. We can save over $150 per year per edit suite simply by sleeping them in the evening and using wake-on-lan to power them up remotely if we need some data in a pinch. Those savings were immediate.
@notlazyjustdontcare: This varies by "charger", too. Some cheap chargers may use more power when not attached to anything, so it's worth trying out different ones. Fancier chargers (like the switching power supplies used by laptops) tend to go to sleep when not in use, which means they're fine to leave plugged in.
While their final point that you can just unplug stuff rather than testing it is valid to some degree, I find that the meter is useful for putting electricity usage into real dollars, and making decisions based on that. We have a spare fridge in the basement where we kept soda and beer. It was a lot easier to decide to turn it off (aside from when we're having a party or something) once I figured out it was costing us $11 a month.
@dialing_wand: Did you also consider the reduction in air conditioner use you'd have if you eliminated the old servers?
In a server room environment it's important to remember you pay twice -- once to provide the power to the system, and once to remove the resulting heat from the room.
Where I work we just replaced some servers with more efficient ones, not because we wanted to save on power use, but because we were out of A/C capacity. Devices like the Kill-A-Watt are handy for calculating this, too, because converting from watts to BTUs is very straightforward.
@segfault: Be interesting to see what happens if you swapped that 60 watt bulb for an LED lightbulb though.
You guys are missing the point. It's not that you should unplug everything. The point is to inform you of how much power the various devices you have around the house are pulling so that you can determine whether or not to unplug them.
Example: I found that the battery charger on my cordless drill was pulling a constant 10W. That's the equivalent of leaving a 60W bulb on for 4 hours a day. It stays unplugged now.
@trellis23: You can get something called a "Smart Strip" which is a power strip with a "control" outlet and several "slave" outlets. The "slave" outlets are only allowed to draw power when the "control" outlet draws more than X watts.
So when our TV is "off" (but still drawing power to maintain settings), the VCR, DVD, Wii, etc., are now "allowed" by the control outlet to draw power. Only when the TV is "on" and drawing a normal amount of power are THEY allowed to turn on. And I really don't care if my DVD clock is right. (You could even put a strip of electrical tape over the blinking if it annoys you that much, but mine doesn't blink.)
There are also "always hot" outlets so the TiVo can stay on even when the TV is off and not letting anything else draw power, or so you can plug in a lamp, or whatever.
The only downside is that to eject a disc, you have to turn the TV on to let the DVD draw juice, and I'm forgetful that way. :)
Two of these -- one on our TV array and one on my desktop array -- save us around $6/month on our electric bill. Not bad.
It's a better option than what my housemates and I did when we were renting an apartment together. We're kinda crackheads when it comes to knowing this stuff and this was before these devices were readily available so we went outside at night with a flashlight and watched the power meter after turning off all the breakers in the apartment. Then we would turn one back on and plug in the thing that we wanted to check while staring at the little rotating disc for 5-10 minutes.
The interesting result was that we found that the power company had labelled all of the meters incorrectly so apartment 1 was paying for apartment 8's power and vice versa. Same for 7 and 2, 6, and 3, etc... We ended up having to pay an additional $400 for our curiosity when we told the power company about the mixup and founf out that we had consumed quite a bit more power than we had been billed for over the previous 6 months.
Looking back, I probably should have confirmed that they issued apartment 8 a $400 refund...
@j-o-h-n: This is why I like my smart strip. When the CPU goes to sleep, the smart strip automatically turns off ALL the peripherals without me having to do a thing. As I said above, one on my desktop array and one on my TV array saves me about $6/month on electricity. I'm sure only a couple pennies of that come from my LCD monitor, but it's no skin off my back and I'm not having to actually DO anything other than use a good power strip (which I'd do anyway), so yay! $6!
Ah, but does the Kill-a-Watt itself waste power?
@ Eyebrows McGee (reply still not working for me!):
Where did you get said smart strip? I need. would be very helpful for our desktop.
I thought that this was going to be an actual study or investigation... because I find these Kill-A-Watts intriguing and have been considering getting one.
So much for expecting something useful out of this article... LAME!! No good information. Not even a summary of the stupid video which is embedded. LAZY!
@Randa the Panda: [www.smarthomeusa.com]
They're spendy, but mine paid for themselves in about a year. From that link you can find them in different sizes, etc. (You can also sometimes find them on sale.)
My local hardware store -- Do It Best -- also carries them now.
I recently got some heavy duty, 3 prong timers. I plug all my unnecessary desk equipment into a powerstrip (printer, second monitor, chargers, speakers) and then set the timer to go off overnight. I put another timer on the TV, stereo, Wii, Xbox, and DVD player. The DVR stays on, as does the cable modem. The rest gets shut off at night. I've been doing it for about a month, so we'll see how my savings are next time I get a bill. :-)
@Coles_Law: DeltaTee has a good point. The fact that the substance of the video was also in a text article should be a little more clear.
And it would be great if videos without text articles could be summarized, so that people who are Deaf or hearing impaired can get the info. (Not toally relevant in this case, but I think it's worth keeping in mind).
@Eyebrows McGee (on Twitter: LPetelle): I've been intrigued by the SmartStrip for some time but no one I know uses them. It sounds like it's useful - but is it user-friendly? Friendly enough that suspicious roommates will adapt quickly to it?
I'd like to be able to shut off a lot of my devices completely (though I understand why some people like to have them on standby to maintain settings, etc). The problem is that unplugging them, or even flipping a switch on a surge protector, is difficult when you have to get behind furniture to do it.
It would be much easier if offices & residences were wired so that every outlet had a wall switch connected to it. Let the user decide if they want the devices in that outlet on or off completely. I don't know what's involved in electrical wiring, but a lot of older & foreign homes have outlets that can be easily turned off. Maybe contractors now figured that people don't want to accidentally 'kill' their computer, tv, etc with just a light switch?
Whatever the reason, it should come back in fashion. I'm sure the cost of extra wiring & switches is very little compared to even surge protectors, and much less than the energy cost.
Yes they work but you can use a surge protector instead. There - I just saved you 1:39.