So I have been Googling all over the place to get a straight answer to this question.
How much will we save by unplugging our (two) cell phone chargers when not actually using it to charge the phones? Every site I find also adds in other things, but none seem to list ONLY the cost of the cell phone charger.
I am getting all kinds of wonderful tips, and most say it is a good thing to do, but seriously, if we are talking a 15 cent savings per year, then it is not worth the time and effort to fumble around every morning and reach behind the dresser drawer to plug it in and then unplug it.
Does anyone have a source for just what a cell phone charger costs to keep plugged in, non-stop, for a year?
According to my charger, it draws 0.2 A at 120 VAC. That’s 24 Watts. Running it 24/7 for a year will consume ~210 kWh. At a national average of 10 cents per kWh, that’s 21 bucks a year. And that’s at full rated draw. Even fully charging the phone while talking on it won’t draw that much. I don’t know what the standby current draw is when it’s plugged in but not connected to a phone is, but a tenth of the full load draw is probably on the high side of reasonable. So, maybe 2 bucks a year?
It would depend on the charger of course; most these days don’t draw much current when the device they’re plugged in to is off, but YMMV. My charger claims to draw 6W, but I imagine that’s peak. According to my KillaWatt, when my phone is finished charging (but still in the charger), it draws under 1 watt. (The meter reads 0). The same when I take my phone out of the charger.
If I’ve asked Google correctly, 1 watt over the course of a year is 8.7 kwh. I’ll pretend your location says only ‘Las Vegas’, which charges ~12.5 c/kwh, so… about 1$/year.
I’ll leave it plugged in today and see if it registers anything over the long-term.
In the interest of Science, I used my Fluke DMM to measure the AC current draw with the charger plugged in with no phone connected. The result: zero. Z-E-R-O. Apparently, it’s a smart charger and only draws current when the phone’s connected. With the phone connected (battery already fully charged) I only measured a draw of 50 mA, which is a quarter of the rated draw. Given the above figures, that would cost me about $5.25 annually.
Huh. I assume they worked a triac or similar into the primary winding to achieve that level of smartness. But now it makes sense as to why chargers are so damned expensive these days.
Which makes me wonder - how many years do you have to use it before the money saved in standby power savings is equal to the additional cost of the charger design.
I don’t understand why you would leave the charger plugged in when you’re not charging the phone. But then, I don’t use my cell phone a lot, so it’s usually not on for more than a few hours at a time and thus doesn’t need to be charged that often.
I leave mine plugged in because the most convenient place for my charger is on my desk, and it’s plugged into the power strip behind the desk.
It’s a huge hassle to get on my hands and knees and fumble under the desk to unplug it and plug it back in to save a dollar or two on electricity each year.
So, multiply QED’s 21/year time all the power supplies in your house (we probably have 20, including all the devices on “Standby”) and you start talking real money, which is why the DOE is pushing for <1W power usage for devices on standby.
I keep mine plugged into the same UPS my computer is connected to so I can charge and use my phone even during a power outage, if need be. It’s a pain in the butt to crawl under the desk every time I’m done charging. So, in it stays.
I started regularly turning off my powerstrips when leaving my apartment, and managed to make my power bill drop by about 3%. That’s my computer power supply, the monitor, the sound equipment, cable modem, etc, etc.
That makes sense. I happen to have an easily accessible but otherwise unused outlet which is conveniently enough placed that I can use it for things like chargers and other temporary-use electrical items. I’m hoping this won’t change when I move later this year.
I leave mine plugged in becuase I have to charge my phone every night. Besides, if I unplug it, someone will move it, then I’ll never find it. OTOH, my electric beard trimmer only needs to be charged once ever other week or so, so I pull the transformer out of the wall with that one since it gets used to rarely.
A previous poster alluded to this, but let me make it a true suggestion. How about running a power strip with an “off” switch from your “behind the dresser” location, or wherever you plug in your phones. Plug your chargers into this power strip. Then turn the power strip OFF when there are no phones in the chargers.
After nearly 30 hrs of logging, my wattmeter has shot up to… 0.01kWh. :dubious: That’s with my phone plugged in 1/2 the time, 1/2 not. (Doesn’t matter, it always registers 0).
I pay 9c/kWh (plus a bit to Bullfrog Power, so call it 10), meaning that in a year, my charger costs me about $0.30.
I’ve gotta say, that’s far less than Q.E.D.'s. I have a printer/scanner that (using my wattmeter) I found used 7$/year even when turned off. That I unplug; my charger I leave in without a care… even more so now.
I’m afraid this is all pretty inconclusive then. If you’re really interested in saving power, think of getting a wattmeter yourself. You can read the thread I started when I initially got it and was giddy with power (measuring). Alternately, your local library may have some deal with the local power company where they loan them out.
I started logging on my power meter when your previous post was the last one in the thread, and my power meter has logged 0.001kWh so far. But I haven’t plugged my phone into it at all.
I have bought some remote-controlled power sockets which makes it much easier to turn off unwanted equipment without scrabbling behind desks to get to the plug.
If they have no powered circuitry, how can they turn on remotely? (I can’t imagine they just turn off, leaving you scrabbling to turn them back on) so they must have a stand-by mode themselves
It isn’t really a serious point I’m making BTW, I imagine they’re designed for (and you’re using yours for) devices with a bigger standby current than a recent phone charger
But if it’s possible to make a remote switch with a negligible stand-by consumption presumably the same circuit can be in anything – hopefully coming legislation in the US and Europe will mean that it is
My power company sent me a handy sheet with monthly estimates of energy usage for lots of appliances. You can see it here. (PDF). It reports that battery chargers for cordless equipment use 4.3 kWH/month.
When I saw all the areas where were using energy unnecessarily (leaving our computers on, for instance), I sat the family down and had a very frank discussion about saving energy. I shared this list and pointed out things that each of us did/didn’t do that wasted energy and challenged everyone to make changes. Our bill is still quite high, but we are saving energy and my daughter took it very seriously for awhile, reminding others when they were wasting energy.
That’s my computer power supply, the monitor, the sound equipment, cable modem, etc, etc.