Keeping your smartphone charger plugged in all night will not send you to the poor house

Keeping your smartphone charger plugged in all night will not send you to the poor house
Most of us charge our smartphones overnight while dreams of super spec'd flagship phones dance in our heads. But it usually takes just 2 hours to fully power up the battery on our phones. So what are the costs financially if we leave our phones plugged past those two hours while we sleep? And what is the cost of leaving the charger plugged into the wall even if the phone isn't attached to it? Read on to find out!

According to Cambridge professor David MacKay, if you unplug your charger from the wall when not in use, over a year you will save the same amount of energy it takes to run a hot bath. In other words, you are not consuming much electricity by leaving the charger in the wall. As Professor MacKay puts it, "Obsessively switching off the phone charger is like bailing the Titanic with a teaspoon. Do switch it off, but please be aware how tiny a gesture it is." If you have your phone connected to the charger, the amount of energy used rises by a factor of ten, but still remains relatively low nonetheless.

A study that dates back to 2012 done by the Lawrence Berkeley National Laboratory revealed that a charger plugged into the wall used an average of .26 watt. When a phone was connected to the charger, the average amount of electricity used rose to 3.68 watt. Once the phone is fully charged, that figure dropped down to 2.24 watt. For the average household, the study showed an average cost of $5.30 to charge a smartphone on an annual basis.

It is no good for your phone's battery to keep your handset charged for long periods of time after it hits 100% charged. This behavior can lead your phone to require a new battery earlier than it would normally need one. Lithium ion batteries, like the ones used by most smartphones, should not be kept at 100% for long periods of time. Experts say that for optimal battery life, you should run your battery for a short period of time, and then plug it in for a short time. It is like having your battery take several short walks instead of running one long sprint. The latter is more taxing for your body.

source: TechRadar



1. Busyboy

Posts: 735; Member since: Jan 07, 2015

That's what they want us to think, so we can use more electricity giving the CEO's more bank.

46. tuminatr

Posts: 1158; Member since: Feb 23, 2009

you could easaly prove/disprove this get a kill-a-watt and test the theory

53. tuminatr

Posts: 1158; Member since: Feb 23, 2009

I found this too its costs about $.60 in water and natural gas to take a shower. So this article says it takes about the same energy to leave my charger plugged all year in as it does to take one shower for me it worth it not to think about unplugging the charger.

61. downphoenix

Posts: 3165; Member since: Jun 19, 2010

a bath typically uses more water and energy than a shower does, about twice as much.

2. Youraveragejoe

Posts: 134; Member since: Oct 31, 2014

So running one bath per household per year.. 7 billion people on earth.. Even if 3.5 billion own cellphones and say 1.75 billion follow this process, we definitely save a lot of electricity!

5. RebelwithoutaClue unregistered

Not to mention there are usually more than 1 charger per person. Tablet, phones,laptops.

7. seanwhat

Posts: 321; Member since: Jul 11, 2013

this is a dumb way to think. if you take anything and multiply it by 1.75 billion you're gonna get a big number.

33. uRiBiTo666

Posts: 55; Member since: Jun 02, 2013

Yes. But, again, compare it to the electricity we use. We have light bulbs that consume at least 60W of power. And we have a few. We have alarm clocks, TV's, ovens, electrical stoves, etc. So the ammount we save doing this compared to the ammount we still use makes the former insignificant.

37. annonymous1

Posts: 15; Member since: Dec 16, 2011

really? how about multiplying by zero =p

9. medtxa

Posts: 1655; Member since: Jun 02, 2014

LOL no! it just mean that every person of that 1.75 billion can save electricity for hot bath once every year!

22. jstine35

Posts: 2; Member since: Jan 19, 2015

1/100th of 1% of total annual energy consumption is still 1/100th of 1% of total annual energy consumption, regardless if you multiply it by 1.75 billion or not. If it's insignificant on an individual scale, it's also still insignificant on a global scale. Unplugging your charger won't change much about the world's energy usage. No one except you will notice.

54. tuminatr

Posts: 1158; Member since: Feb 23, 2009

its a odd argument think about this if you just took a shower every other day rather than every day you would save as much energy as having 182 charger plugged in for a year. And then if you switched to just chargeing in your car and did not charge at home you should start a hash tag #savetheplanetchargeyourcellinyourcar

56. Z3R091 unregistered

Nice intro Alan F. "Most of us charge our smartphones overnight while dreams of super spec'd flagship phones dance in our heads."

3. Settings

Posts: 2943; Member since: Jul 02, 2014

But who wakes up at 3AM to charge their phones?

13. chocowii

Posts: 478; Member since: Jan 30, 2014

Hugo Barra does.

4. gaara6775

Posts: 738; Member since: May 20, 2014

Sorry but I simply off my phone at night & go to sleep.

6. rphunter

Posts: 21; Member since: Nov 02, 2014

OK, if it is not a good idea to charge the phone overnight, WHY does Apple suggest this in its documentation? I have been doing this since 2009, with several phones, and have not ever had a problem with a phone battery. My wife does the same thing, so that doubles the time period. The power use is about the same as an electric clock, So maybe I should unplug those when not in use too? Insane! You will save more electricity by replacing ONE incandescent light bulb (60 watt), with a CFL bulb each year. I noticed when I reaplaced all my incandescent bulbs with CFL bulbs, my electricity use dropped about 40%, and the next month, the electricity rate went up 50% You can't win!

11. god996

Posts: 34; Member since: Oct 27, 2013

Wow, a literal iSheep!... You would probably jump off a cliff if Apple suggested to in its documentation? Maybe you are lucky, or maybe I'm not because I, for example have a few phones with nearly dead batteries because of overcharging. And now I have a Nexus 5 and if I unplug it for the night, its battery won't drop for more than 2-3% in the morning. I think that's not much of a loss.

16. pocketbook

Posts: 21; Member since: Mar 26, 2014

lmao, overcharging isn't even a thing anymore. Lithium ion batteries have a failsafe built in to prevent exactly that.

43. avidSomnambulist

Posts: 3; Member since: Jan 20, 2015

"Wow, a literal iSheep!" says the Nexus 5 owner.

44. avidSomnambulist

Posts: 3; Member since: Jan 20, 2015

Just FYI, this is being posted from my own beloved N5. I'm probably already familiar/agree with all the arguments you can present for buying/owning one. Just poking fun.

40. hmmm...

Posts: 81; Member since: Jun 05, 2013

You only save electricity if you replace it with a lower watt CFL. If you replace a 60watt bulb with a 60 watt CFl, it is essentially the same. I think a 60w fluorescent tube will be better than a 60w incandescent bulb... and you can tubes that contains no mercury unlike CFL

52. andynaija

Posts: 1264; Member since: Sep 08, 2012

All fluorescent lamps contain mercury.

55. tuminatr

Posts: 1158; Member since: Feb 23, 2009

They do but it’s not truly dangerous unless you breathe it in the fumes as you break a bulb

62. hmmm...

Posts: 81; Member since: Jun 05, 2013

Thanks for the info...

8. Yogurt

Posts: 3; Member since: Jan 19, 2015

What in the world is the matter with you commenters? 1) This is about saving money. You act like electricity needs to be saved but it doesn't. Electricity is unlimited. 2) It says very specifically that you should unplug your charger. It just goes on to say that it's not exactly going to save your pocket a whole lot of money. 3) Savings is a personal thing! I am not saving electricity for my neighbors, I am saving it for my wallet. Therefore trying to say "Sure it might not be much individually but if everyone worldwide unplugged their charger it would add up" is a bunch of garbage. No one is doing it for their fellow man. 3B) It does not even add up! 8 billion people in the world. let's say they all own 3 devices which is ridiculously high. At 5.38 per device per person per year, that would be a worldwide cost of 129 billion dollars per year. The united states government spends 2000-4000 billion each year. (2-4 trillion). That's just one country in the world. 4) Want to know how much you can save on electricity? Take a look at your monthly bill. That number on there is the very most you can save ever. That is the very definition of savings. It could add up if you change certain parts of your life but then again you might decide it is not worth it. For example, let's say you run your heater all month and your bill is 120 dollars. Next month you go completely without heat, the bill is 60 dollars. You saved 60 dollars but I personally would rather spend the 15 dollars a week for heat. You could go without a refrigerator too but I wouldn't recommend it.

10. medtxa

Posts: 1655; Member since: Jun 02, 2014

Lol right, is alot money for one person...not for 8 billion.

12. RebelwithoutaClue unregistered

Electricity is unlimited?

15. jaytai0106

Posts: 1888; Member since: Mar 30, 2011

I think he might have discover the power of fusion. Then electricity is unlimited.

20. lallolu

Posts: 733; Member since: Sep 18, 2012

That was the funniest comment I have read all day on this site. And he said it with such certainty :)

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