Energy tip #10: remove wall warts and slay electricity vampires

recharger.gifAre you plugged in? If you have ever left rechargers or unused appliances plugged into the electrical outlet, you may be in for a bit of a shock. The U.S. Department of Energy tells us that not only do appliances continue to draw electricity while the products are turned off, but in the average home nearly 75% of all electricty used to power electronics is consumed by products that are switched off.

VCRs, televisions, stereos, computers, and kitchen appliances all use energy while not in use. You may have noticed how a cell phone recharger can be warm even when not attached to a phone. The best way to prevent unnecessary energy expenditures is to do a clean sweep of your home. Here at the office, we’ve gotten into the routine of unplugging our water cooler at night. The process is a bit of a hassle at first, but hassle quickly turns into painless habit.

(Bonus question for engineers: can anyone explain why products can’t be designed to prevent this sort of passive energy use? Is it simply laziness on the part of the manufacturers, or is there a real design constraint at work?)

The good folks over at Ideal Bite have previously tackled this issue and suggest the following:

  • Use power strips to turn off TVs and stereos. You’ll save the energy equivalent of a 100-watt light bulb that is always on.
  • Unplug chargers (think cell phones and iPods) when not in use. Only 5% of the power drawn by a cell phone charger is used to charge the phone. The other 95% is wasted when it is left plugged into the wall.

Let’s runs the sums:

Rough equivalent: 100 W light bulb @ 8760 hrs/year
Electricity: $.10/kWh
Total energy cost: $87.60
Cost of power strip: $4.00
Total energy savings: $83.60
Total CO2 savings: 1217 lbs.

We took a week off to launch our new Expedia partnership as well as Home and Dorm TerraPasses. The extra time allowed us to garner some additional votes on the duct fix (Tip #9). 22 people have said ‘Yes’ to getting their home’s ducts inspected. If 50% go ahead with the project, we can expect about 41,800 lbs of CO2 being reduced, or about 6.3 tons of waste recycled instead of landfilled.

Author Bio


Comments Disabled

  1. Scott K - September 13, 2006

    Being both aware of this problem and lazy, I purchased timers for some of my home appliances with ‘wall warts’. But I wonder if the power draw for the timer more than offsets the energy saved?

  2. Diane - September 13, 2006

    Thanks! I’ve unplugged my charger, my bedroom lamp, and a livingroom lamp from the wall. It’s easy enough to learn to plug them in when their services are needed. Would you consider making this article into a format which could be emailed to friends who might be inclined to make similar choices?

  3. 1985 Gripen - September 13, 2006

    In a similar vein, computer peripherals (the stuff the plugs into the computer such as printers, scanners, speakers, the monitor) continue to draw power when the computer’s shut down or the device is plugged-in and not in use. I’ve read it’s the same power wasted as leaving a 60W light bulb on all year.
    There’s a power strip/surge suppressor (called the “Smart Strip”) I’m in the process of buying (let me assure you I have no vested financial interest in the product other than the fact I’m dropping around $30 to buy one) which will automatically shut off all your peripherals for you. You plug the computer itself into the “control” outlet and the peripherals you wish to turn off along with the computer (printer, speakers, broadband modem, monitor, scanner, maybe your desk lamp, etc.) into the other outlets. When you shut down your computer the power strip automatically shuts down all the other devices for you. When you power-up the computer it turns them all on! Here’s the web address of the company which manufactures/sells this product: Just beware if you have a Mac, IBM, or Dell computer you need to buy the 2nd generation one. There’s a disclaimer on the website.
    You can also use the Smart Strip to control your home entertainment system. For example, plug the receiver into the “control” outlet and all the other components of your audio system into the other outlets so when you power-on the receiver everything else comes on-line.
    This website (see lower portion of page): claims that you’ll save enough money on your electric bill to pay-off the cost of the Smart Strip in as little as six weeks! That seems a bit hard to believe, but you’ve gotta’ figure that you ARE saving energy and keeping greenhouse gases down by turning off stuff that would normally be in “standby” mode, using “idle current”. In fact, I recently read that Britain is considering a bill banning consumer electronics manufacturers from including a “standby” button on their electronics.

  4. disdaniel - September 13, 2006

    I think they suggested unplugging chargers and electronic equipment (TVs, stereos, VCRs, computers) and appliances when not in use. I’m pretty sure unplugging unused lamps, while it may be good exercise, will not save you much electricity.
    To the editor:
    “If 50% go ahead with the project, we can expect about 41,800 lbs of CO2 being produced,”
    Eeek, now it looks like even our energy saving projects are producing CO2! [Ed. — Thanks, fixed.]

  5. Ian - September 16, 2006

    I am not an engineer, but as far as I know, there is no design constraint that requires things like TVs to consume power when not in use. However, it’s what consumers have demanded.

    TVs consume power when turned off so that they can start immediately when turned on. You may remember that old TVs sometimes took 5 or 10 seconds to reach full brightness. Now they start almost instantly. A small amount of juice constantly flowing into the TV to keep it on “standby” is what makes this possible.

  6. disdaniel - September 21, 2006

    “it’s what consumers have demanded.”
    I bet most consumers have no idea this feature exists…so how can your statement be true?

  7. Stay Green - March 6, 2007

    I have rewired my house so that all I have to do is flip a few breakers off at night–which closes the electrical current flowing to the outlets — then if I need to use something I just flip the breakers back on– funny thing I’ve noticed that I haven’t had the need to turn on the living room lights in weeks —
    Stay Green

  8. Princess Paris - February 15, 2008

    I have been going around unplugging electronics and appliances not in use for ages and so glad I found this link. Everyone who knows me knows about my habit, now I can send them this link…

  9. Aaron - February 20, 2008

    saving energy is good, but not solving the problem, when the consumer changes its habits to conform with the energy companies the consumer loses the upperhand. the problem should be solved by using clean burning energy. In turn a consumer would only waste their money and not CO2.l
    I feel the idea means well, but also lends its self to thinking energy will always be bad. Energy is good. clean is good.
    We can’t be ruled by energy crisis. we must find other sollutions that unplugging our cell phones.
    [Ed. — we basically agree in the general sense with this sentiment, but we also note that there is a difference between the short term and the long term. Right now energy is not clean, and efficiency measures help a lot.]

  10. Mame - March 24, 2008

    I have a new home ith lots of sky lights, I have been unplugging most everthing when not in use.
    My electric bill is only $50.00 per month.
    I really does pay

  11. Tom - April 9, 2008

    I agree in principle, but one of the things that might keep a lot of people from doing this is the fact that a lot of TV’s, VCR’s, DVD Players, etc., either have a setup menu that has to be revisited or a clock that has to be set. Going through this for every appliance can become a bit of a pain. If the manufacturers would build in a battery backup for this, it would be easier.
    I agree that unplugging charges is a no-brainer.

  12. J.V. - April 21, 2008

    I am an electrical engineer, so I’ll give you some insight on why products use “phantom power”.
    Most modern electronics use low-voltage DC power internally, but a wall outlet supplies higher-voltage AC power. A converter is required, and these are inefficient and usually never turn off, especially if it is an external “brick”. Another issue is that if the device has internal memory or a clock, these require a trickle of power. Many electronics could be designed to use no energy at all when turned off, so if consumers start demanding it, we can vote with our dollars.
    Simple appliances such as light bulbs, vacuum cleaners, toasters, and simple ovens without a clock use absolutley no energy when they are plugged in but turned off.
    Many appliances like microwaves and coffee makers use very little energy when plugged in, but turned off. Around 10 cents/month maximum.
    The biggest offenders are devices with external “bricks” (which run about 3-5 Watts when turned off) and high-wattage electronics such as stereos and computers (which run up to 20 Watts unplugged). Leaving a computer plugged in could cost you up to $1.50 a month even if you never turn it on.
    The statistic on the DOE page that states “75% of our energy is used by devices that our switched off” is absolutely false. The real number is closer to 5%.
    For more info, check out this person’s fact-checking

  13. emln - July 24, 2008

    I am in agreement with the idea of conserving energy and using our resources wisely. But, I do not agree with the statement that tons of co2 and other gases are emitted into the air, because a small transformer was left plugged in. We need to keep the numbers real. If we can’t maintain creditabilty in our facts, then the objective is lost.

  14. Marcia - September 4, 2008

    For clarification, if I leave a cell phone charger plugged in but not connected to the cell phone after it is charged, does that draw power; if so, does it draw the same amount of power as when the cell phone is in the charger but fully charged? Same with toothbrush chargers which sent me on this quest for information.

  15. Adam Stein - September 4, 2008

    Hi Marcia — the charger will draw a small amount of power when not attached to the phone (or toothbrush), but not as much as when the appliance is attached.
    If you leave the charger permanently attached to the wall, though, over time it tends to draw more “phantom” power than power for actually charging, simply because it’s drawing a phantom charge for so many hours during the day.

  16. dave - October 1, 2008

    Last month I purchased 6 small electrical switches at HD, each $3.50. They plug into electrical outlets and have a on-off switch on top. They do not use any electricty when not in use (measured my self) I use them for:
    coffee maker: has a build in clock
    water boiler: has a lamp
    swiffer vacuum cleaner: has a charger
    3 cellphone chargers
    radio: on standby
    toothbrush charger: has a light
    shaver: has a charger
    An appliance is plugged into the switch so you can full power them on and off by the flip of a switch. Yesterday the electricity bill came: 232Kwh last month – september- compared to 241Kwh the same month a year ago (238 Kwh in august this year). So year of year, I saved: 9 Kwh (3.7%) that at $0.11559 per Kwh saved me $1.04 this month. Comparing with the month before is less correct. At this rate and KwH cost, it will take me almost 1.5yrs to earn back the $21 I spent on the switches, but that is worth it (assuming no increases in the price of electricity….). These switches last a lifetime.
    My 3.7% reduction is pretty close to the estimated 5%, so I think 5% is a good general estimate and it shows how much energy we can save; when I make coffee, I power the maker on, brew my coffee and afterward I power it off, no inconvenience at all, especially when you know I am savings a few dollars and CO2 emissions.
    I do not have switches installed for me Microwave (has a clock), TV, Computer and DVR receiver for some of the following reasons:
    Computers, especially external hard drives etc do not farewell when fully powering and de-powering all the time. Of course, I turn off my computer after each use and switch of the screen, printer etc too. But no full depower. It will shorten its lifetime. And that will be much more costly and environmentally less friendly.
    The same goes for the DVR receiver. It will not record anything if you want to do so, and it will lose all programming and channel info. It will take up to 30min after powering to have channel programming reinstalled (the receiver needs to communicate with the cable provider and establish an new connection).
    If I would install electrical switches on these three items, I am sure my net electrical savings will be over 5%.
    If all house holds in the US would do the same, we could save:
    1,140 billion kWh (2001 electricity consumption all US housholds)
    1.35 lbs CO2/Kwh (1999 number for C02 emissions per Kwh generated in the US)
    5% energy savings
    1,140 billion Kwh x 1.35 lbs/Kwh x 0.05 = 77 billion lbs of CO2…
    Total U.S. carbon dioxide emissions from fossil fuels reached 11,968 billion lbs in 2007, of which ~33% was from cars. So this 5% will decrease the total US CO2 emissions by almost 1% (includes energy consumption growth from ’01 to ’07) which is equivalent to taking roughly 675 THOUSAND cars of the road. Not bad, not bad at all.

  17. Adam Stein - October 1, 2008

    Dave, you’re awesome. Do you have any idea how your heating and cooling costs compare to last September? Weather fluctuations can swing your energy bills quite a bit. You’ll need to track over several months to truly gauge the benefit of the switches.