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Phone chargers – Keep plugged in all the time or unplug?

By FPL Expert

Asked on: August 13, 2013 by Richard R., question via www.FPLBlog.com

Does it take more energy to leave a phone charger in the outlet, even when it isn’t charging?

It’s true most of us leave our cell phone charger plugged into the wall even when we’re not using it. The good news is that while the charger does use a tiny bit of power when left plugged into the outlet, it’s only about 23 cents a year for an FPL residential customer.

This small amount of energy use is called “phantom energy.” Power adapters, like cell phone chargers, aren’t the only items that use a little bit of energy when they’re plugged in. In fact, many electronic items are in “standby” mode when turned off, helping them turn on faster or respond to a remote control. Devices with lit digital displays use power too, albeit a very small amount. You can avoid this by unplugging unused items until needed or using power strips to cut power to multiple items with one switch.

As far as cell phones are concerned, they use very little electricity even when you are actively charging them. In fact, the annual cost of charging your phone eight hours a night is just 65 cents if the phone is off while charging or $1.30 per year if it’s switched on. Not bad for a convenience most of us can’t live without.

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Comments [66]

  1. Elaine

    I have a single family house ten years old with a programable thermostat. I don’t have a dehumidifier. What is temperature should I leave the house when I am up north for the summer and fall.

    1. michelle

      I would like to point out at 23 cents per year per person that is still like 50 million dollars, or more!, a year when you do the math, I’m not an anylyst, but I don’t think thats very sound advice. One has to look at the collective and not the individual. I don’t think the generl public thinks that way and it’s your responsibility to give them sound advice! I feel that it’s misleading and irresonsible to promote it that way.
      Thank you, Michelle

  2. GregP

    I was skeptical of this claim, so I attached a current meter to the power mains side of my cellphone charger. Once it hit 100% charge, the current draw was zero.

    This may not always have been true. A few years ago, the chargers were the transformer-type, and not the solid-state type, and continued to consume a little power after full charge. The newer ones all stop consuming any power whatsoever once the device is fully charged.

    In light of this, it makes no sense to me to unplug my charger for any reason. Especially when doing so increases wear on the wires and connectors, increasing the risk of fire. It also increases the chance of having a dead battery when I need it.

  3. George Roy

    I normally keep my daytime temperature at 79-80 and nighttime at 77 or 78, depending on how I feel. I am retired, so adjusting the temperature more often would not make sense.

  4. gary

    So the original question between crock pot and oven wasn’t even addressed. Was all about microwaves.

  5. kirtesh

    when you want to charge your phone then only plug it due to it takes some little current when it is pluged but not charging phone

  6. joyce

    clothes dryer
    why not use the sensor setting on your dryer.
    using the high heat setting is hard on your clothes.

  7. Mike Cipollone

    That comment is right on the money. One million people each saving a small amount of energy translates into lots of energy and money saved. It pays to look at the big picture.

  8. Jeremiah Dailey

    I saved $65 my first month when I insulated my attic with r-38 insulation. My house stays cooler longer and my air conditioner runs half as much as it used to.

  9. Katherine

    Hello – My son-in-law prefers to iron his own shirt every morning. He turns the iron off but leaves it plugged in – and that has always worried me re: shorted outlet, possible fire,etc. Is it pulling any current when off and do you think it can be a danger? Thank you!

  10. Lewis Regner

    Microwave ovens could be designed and built with this feature, as is are some models of alarm clocks. It could be done with little additional cost but still, it’s an “additional cost” and enters into the manufacturers’ calculations on profitability, the design change and feature incorporation having to promise a certain return on the investment, BEFORE being considered feasible. An external battery compartment with a replaceable battery, or even a self maintaining rechargeable internal battery to keep just the low current part of the microwave oven’s circuitry responsible for clock and settings functions “alive” in the event of a power outage. Both alternatives to providing this feature add another layer of maintenance to the oven though, and again, cost. So far, it seems, no manufacturers have considered it a worthwhile thing to venture into doing.

    UPS devices like those available for computers, in case anyone is considering them for the job, are woefully inadequate in the current capability department, should power ever go out while the oven is in operation, and would fail to function (or fail completely) in that eventuality. Microwave ovens are very high current devices, some having more than four times the current demand of the most demanding computer system. It won’t work. DON’T try it!!!

  11. Terry Jones

    How can I tell if my old refrigerator is using
    too much electricity. It looks good but how efficiant is it.

  12. Richard N. Downing

    Your comment input closed before I could state my Question you promised to answer.
    Here is the question again.
    You recommend using a “Smart” strip on our computer & TV to shut down periferrals when the TV & Computer are shut down. Question is, will it work on my computer that goes into hibernation, but doesn’t turn off.

  13. Richard N. Downing

    I’m still waiting for a reply that was promised to me by your energy expert six months ago about his idea of using “Smart” strips on computers & TV sets.
    I asked at five electronic stores for an answer to my question, and though they carried the product you recommended they could not answer my question.
    You said you would answer it in a few days. I’m still waiting.
    The question:

  14. John Foy

    Looking at energy consumption through an expense-only lens is not as good as eliminating even the tiniest, non-essential consumption of energy. Across millions of consumers an individual tiny non-use sure adds up to helping reduce carbon emissions.

    1. Tim Robbins

      The comment about plugging your phone in ‘counts as a charge against it’s 500 or so lifetime of charges for the battery’, is not true. The 500-1000 cycles for a battery refer to full discharge cycles, not partial ones.

      So if you discharge it 5% X 20, then that would be roughly 1 cycle.

  15. Jon

    I agree, even though the amount of electricity used is small, I thought the advice would still be to unplug, since that attitude of “a little bit doesn’t matter” is naive.

    A little bit times 50 million households, makes a A LOT.

  16. Diane Wright

    One year we unplugged our cordless
    phones when we went North and none
    of them would work when we returned to FL.
    Also true for our computer. Apparently
    there is a battery in the computer that
    needs to be kept charged. Our computer
    would not work after being unplugged for
    about 6 months.
    However, for the past couple of years
    we have unplugged our computer and had
    no problems. We still leave our cordless
    phones plugged in.

  17. Rafael Giusti

    I am glad to see people responses concerning about wasting energy even when it seems very little.

    As an Electrical Engineer I believe designers can do a better job to reduce that waste to Zero. It is just a matter of setting the goal and executing it.

    Educating consumers is also the key for this type of issues.


    Howmuch electric does the box for cable and computer use? Does it pay to turn the box off when gone for the day?

  19. CCh

    Is there a more energy and cost efficient time to run the washing machine and clothes dryer? How about the dishwasher?

    Thank you.

  20. antonio taveras

    This small amount of energy may sound insignificant when taken into consideration on an individual basis. The response should be when all of this ‘phantom energy’ is wasted by the millions of electronic device users in the country and worldwide. Mr. Muccio, please give us a real number.

  21. Granville Smith

    thanks for the useful info.Question!,does it pay to turn off power to the water heater until needed if hot water is used only once a day.turning it back on only when needed.Thanks.G s.

  22. ramon ramos

    Contd. with the electric trivia, like the cell phone cords/charges is interesting. One could make a educated cosumer election if or not to plug or unplug for conveniences!

  23. Pat Lowe

    Talk to us about surge protectors. I was told, when purchasing a new television, that it is most important to plug it into a surge protector.

    Please advise as to what type of surge protector (specific specification) would be best for a large television?
    What type surge protector is best for your computer?
    What about a stereo system?
    What appliances should be on a surge protector?

    Guidance would be appreciated.

    1. lesa major

      I wanted to know your thoughts on how much energy is used by the air condition. I have noticed that when i turn it completely off when its not very hot, then turn it back on when it is. My bill was cheaper than when i just left it on automatic fan. Some of my friends say its chepear to leave it on. Plus this prevents wear and tear on the ac unit. I found my bill to bill twice as high when i left it on.


      i need new air ducts & want to know how can i replace them on time payments & who will do it. I am a sr with small income & cant afford much.

  24. barb abernathy

    can I leave my laptop plugged in and on all day long?

  25. Richard Sandoval

    Does a toothbrush charger have the same energy consumption proportions.

  26. Elizabeth

    I thought it might be some sort of electrical hazard leaving the charger plugged in, Iam glad to know it is not and it is not using a lot electricity. But I am still going to try to unplug it from now on hay .65 to 1.30 is a can of something additional I could have.

  27. Lisa

    Great…. A load of my mind!

  28. eleanor shepherd

    at our house, we always unplug our coffee pots when we have finished our morning coffee, we always leave the microwave, toaster, all appliances unplugged unless we are using them, same with lights and fans, if not in the room, all are turned off..on s.s. we need to save on our expenses…leave the a/c at 81 all summer, too.

  29. Louides Christalin

    These are good info. Glad to know…

  30. Susan Joo

    When one person energy-saving is only 23 cent a year, half of the country would save $ 23 million just unplug their phone-charger, when it’s not in use. I unplug it every time, because my belief is, we could save ton’s of dollar worth of energy, water, food, whatever with more unselfish mentality. Many little things add up huge amount.

  31. Rita Levy

    If you are constantly working to improvre service & are planning on raising rates why did we lose power in my community 3 times within the past 2 months without any storms I was told it was FPL equipment.

  32. Rudy Jones

    please refond my deposit….Thanks. 😎

  33. art bergman

    There is at least one smart charger that consume no phantom power at all. I have a PowerTrip made by Powerstick.com that shuts off completely once my phone or iPad is fuly charged.

  34. Gerald Young

    OK I have a similar question on electric hot water heaters. Since I traveled a lot, I got into the habit of turning my hot water heater off at the circuit breaker while out of town and I believe it saved me some money.

    Once I retired, I am leaving my 40 gallon heater off most of the day and only turning it on about 10 or 15 minutes before my daily shower and then, turning if off again. Fact of the matter, my heater is off more than it is on.

    My thinking is that I must be saving money otherwise retailers like Home Depot wouldn’t be selling timers to put on these water heaters and devices to replace heaters that heat water as it is used.

    So how much does turning off my water heater save me?

  35. Marvel

    Nice to know it is such a small cost per year, per charger but when I think about all of the cell phone chargers out there… If we ALL unplugged that would actually result in substantial energy savings. Think globally, act locally. :)

  36. Addy Temme

    I do unplug most items in my home, however I do like to be reminded from time to time to time.


    What uses less energy on your drier – LOW heat for longer time OR HIGH heat for shorter time?

    1. sandra hamm

      it’s easier and cheaper to get a protector that wires into your breaker box and eliminates all those surge protectors. we bought ours at menards. i’m sure home depot etc. prob has them. i answered you before but it put it under a comment that didn’t remotely connect. hope this goes to the right place

    2. sandra hamm

      we found that it was easier to get this gizzmo that my husband bought at menards ( a lumber/ hardware/ everything store ) and it was a simple attachment to your breaker box than to have to buy all those strips to protect against power surges. it was only about $50 and that’s even cheaper than buying all the strips it takes to protect everything in your house. directions included and believe me my husband is no electriction and he had no problem at all. he said it was easy

  38. angelina roche

    my computer is on 24/7/ days is that use to much energy?, Do i have to shut off?

  39. Bob

    Even at $.23/year per phone, add your tv, speakers, dvd, xbox and everything else around the house bleeding phantom electricity when not in use and we might be more surprised at the total amount. Do yourself a favor and use a power strip and just click everything off at bedtime.

    It’s amazing how many digital, rechargeable items we now keep around the house. We always had a junk drawer when growing up that held assorted nuts and bolts etc. The junk drawer of today now consists of more chargers then I can count!

  40. Debra Nagle

    My sister in law’s house burnt down from leaving a cell phone charger plugged in! This was determined by the fire department. My charger gets hot for my phone and iPad! I never leave the chargers plugged in unless charging the units!

  41. Allan

    Annoying Problem Department

    We have one of those Microwaves that every time the power is interrupted even for just a moment its clock/date has to be fully reset before it can be used. Does anyone make devices with on-board back up power supply that does not require a complete reload of time and date???

  42. Matt

    @Greg, we should look at the collective picture where most homes have 2-4 of these plugged in and then multiply that times virtually every household in the country, then the world.

    I am sure the collective energy savings would amount to something useful even at the city or state level, but you’ll have to ask the experts on that actual figure would be, not to mention the savings in natural resources.

    If I was NextEra Energy (FPL) servicing 26 states electrical needs, I would be telling my customer’s to go ahead and leave them plugged in too! That extra $1.25+ per year might not mean much to each individual, but to Nextera, I am sure that $1.30/household x millions of customers is nice to have at the end of the year.

  43. Ellen Berman

    What’s the verdict on whether keeping your cell phone plugged in even when it is fully charged is good or bad for the battery. Some battery stores say you should only charge it when the charge is gone. If it’s plugged in all the time it diminishes the lifetime of the battery since batteries are only good for a certain amount of charging. Do you have an opinion on this?

    1. kat

      can you tell me the cost approximately to leave ceiling fans on 24/7? i like to leave them on to keep air circulating even when it is not “hot”. does this actually help by the way?

    2. captain

      I took the FPL Home test and have heard from numerous FPL employees that if you leave a fan on 24/7 it costs $7/mo per fan. YES it is wasteful to leave on when you are not in the room. A fan does NOT keep a room cool, it keeps the person cool

  44. paul tucker


  45. LARRY

    I could do commercials for FPL, every encounter I have with them is outstanding, no matter where I have lived. I am in St.Lucie County, one block outside the Fort Pierce city limit, and actually on the other side of Fort Pierce Utilities headquarters. They are THIEVES. Luckily I have FPL; my three bedroom house costs far less than some pay to Ft Pierce Utilities for a much smaller house. Vero Beach Utilities is even worse. THANKS, FPL!

  46. Handy Randy

    recharging a cellphone may reduce the life of the battery, since each time it is plugged in for recharging, the lithium-based battery will count it as a charge, and its life is limited to a certain number of charges (say 500). so you could have less than 18 months of life if you plug it in every day, or you could have over 9 years if you plug it in once a week.

  47. Jack Alexander

    Thanks for telling the truth and for pointing out the reasonableness of cost/convenience. Before I retired I worked for a northern utility as engineer, manager, and eventually finishing up as a government/public/media relations rep. You cannot believe (or maybe you can) the amount of incorrect info some folks just throw out there with zero data but a great deal of emotion.

    Commitment and feeling are important, but a few facts are too. Thanks for the facts.

    Again, thanks!


  48. Richard Nolan

    Mr. Muccio, I have heard that cell phone charger unit can sometimes cause/start a fire. Is this true? If so, cell phone chargers should NOT be left “plugged in”. If it is not true, I guess we don’t have to worry! Can other chargers (i.e. rechargeable flashlight) cause/start fires? Thanks for you efforts to keep people informed. Richard Nolan

    1. Michael Fairhurst

      Some phone chargers, however develop quite a bit of heat when left plugged in endlessly, to lessen fire risk unplug in any case when done.


    How much energy does a pool pump use?
    How much energy does a neon light use?

  50. Deb

    I’m glad too, that it uses so little! I would like to see the numbers on computers. Last summer I wasn’t living in my home, so I tried to get the power bill down as low as possible without actually shutting it all down. At one point, I only turned of the monitor and printer. I didn’t shut the computer down completely because I needed to be able to connect remotely. When I was able to shut it down completely, there seemed to be a significant difference. however, due to other factors, I can’t say for certain that it was the computer drawing the power. If someone hasn’t asked the question yet, I will have to. Thanks, FPL, for the info.

  51. Irma

    Yes, but if you take a million people leaving their chargers plugged all day isn’t that wasting energy? One household paying $1.30 a year is not what I am concerned about, is the million customers unplugging their charger when not in use how much would that save in energy? Is it worth it then to unplug?

    1. Pat

      That’s exactly the problem. It’s all about the cumulative effect of so many people doing wasteful things. I think of the graphic I saw somewhere about how inefficient the power plants are in the U.S. All the waste is horrible.

  52. carl barta

    Ref : Leave cell phone chargers in the outlet.
    A very strange advise. So what you are suggesting is to waste 2 kWh of power every year for nothing- with my 2 cell phones that would be 4 kWH. That is more than enough to bake my bread. Also, those 4 kWH convert into heat, so if you use A/C you will need additional power to cool it down.
    yea, it’s the multitude of cell phones, tooth brush, TV set, computer gateway ( the ATT u verse gateway sucks 51W on stand by!)and dozen of other things and before you know you need a new nuclear power plant.

  53. Marva Lewis

    I need help in lowering my monthly bill.

  54. stella garofalo

    If I have power surge coverage from FPL, does it protect my refrigerator or do I need a separate power surge protector.

    1. joyce

      save yourself time and money by using an automatic thermostat. that way you don’t have to come home to a hot house, but you still save lots.
      be sure your duct work and ac unit is in good condition. update to a more energy efficient unit.
      it will pay for itself.

  55. Greg

    Whew…I was worried that I was wasting a ton of energy and money keeping my phone charger plugged in all the time. Glad to hear I’m not doing too much harm.


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