Lori Bongiorno

Energy vampires: Fact versus fiction

image name and credit

It's well-known that most electronic devices in our homes are sucking up energy even while they are turned off. But for all the information out there, many questions remain. I got hundreds of reader questions after writing the post What's wasting energy in your home right now. Below are answers to the five most common inquiries:

Which electronic devices waste the most energy when they are turned off but still plugged in? 

Set-top cable boxes and digital video recorders are some of the biggest energy hogs. Unfortunately, there's little consumers can do since television shows can't be taped if boxes are unplugged. It also typically takes a long time to reboot boxes.   

However, some of the other major consumers of standby power are more easily dealt with: computers, multifunction printers, flat-screen TVs, DVDs, VCRs, CD players, power tools, and hand-held vacuums. The Lawrence Berkeley National Laboratory (LBNL) measured standby power for a long list of products.  

While it's true each individual product draws relatively little standby power, the LBNL says that when added together, standby power can amount to 10% of residential energy use.

Why do electronic devices use energy when they are switched off?   

Electronics consume standby power for one of two reasons, says Chris Kielich of the Department of Energy. They either have an adapter that will continue to draw electricity, or they have devices (such as clocks and touchpads) that draw power. Anything with a remote control will also draw standby power, she says, since the device needs to be able to detect the remote when it's pushed.

Does everything suck energy when it's plugged in and turned off?

No. If your coffeemaker or toaster doesn't have a clock, then it's probably not using standby power, says Kielich. Chances are your hair dryer and lamps (although they may have a power adapter for the dimmer) are not drawing standby power either, she says. Devices with a switch that physically breaks the circuit don't consume standby power.

Will switching things on and off shorten their life?

Probably not, says Kielich. You'd have to turn devices on and off thousands of times to shorten their lives. The real downside, she says, to unplugging electronics is that clocks and remotes will not work, and you do have to reset everything.

Can you ruin batteries by unplugging battery chargers and causing batteries to completely discharge?

It could be a possibility, says Kielich. Her advice: Don't let batteries get completely drained. But you don't need to have things like hand-held power vacuums and drills plugged into the charger when it's 100% charged, or even 50% charged.

Power Strip FAQs

Plugging electronics into a power strip and turning it off when you're not using it is a widely prescribed solution for curbing vampire power. Here are answers to common questions: 

  • Power strips draw energy when they are turned on, but not when they are switched off.
  • Any decent power strip should have surge protection, according to Kielich. Flicking your power strip on and off will not create a power surge capable of damaging electronic devices. In fact, it will protect devices from other surges. 
  • Several readers were worried about the possibility of fires caused by plugging too many things in at once. If you plug in the allowed number of devices, then power strips are safe, says Kielich. Just don't plug your power strip into another power strip, or you run the risk of creating an overload. 

Environmental journalist Lori Bongiorno shares green-living tips and product reviews with Yahoo! Green's users. Send Lori a question or suggestion for potential use in a future column. Her book, Green Greener Greenest: A Practical Guide to Making Eco-smart Choices a Part of Your Life is available on Yahoo! Shopping and Amazon.com.

Email IM Bookmark del.icio.us Digg

You do not appear to have Yahoo! Messenger installed. Click here to download and install it.

Email this article

There is a problem with one or more email addresses entered

Enter email addresses, separated by commas.

There is a problem with the email address entered

Email addresses will only be used to email this information on your behalf and will not be used for any marketing purposes.

Alerts

Get an alert for updates:
  • from this author
  • on Electronics
  • on Electricity
  • on Saving energy at home

View All Green Alerts »

comments from our community

Showing 1 - 15 of 645 comments

Post Comment
  • Posted by sunil s Mon Mar 2, 2009 2:22am PST
    Thanks for sharing information and i appreciate it.Looking for more discussion and waiting for new topics here. Service Audio
    Report Abuse
  • Posted by buggs Sat Mar 7, 2009 8:27am PST
    next we need to unplug clocks. anything with a remote uses power when off...but the remote is useless if power is turned off......i wonder how much power i wasted replying?
    Report Abuse
  • Posted by Bart Sat Mar 7, 2009 8:28am PST
    Computers are an exception to turning off. They should be turned off when not in use in general. However, turning them off and on dozens of times per day can be extremely hard on the hard drive.
    Report Abuse
  • Posted by george l Sat Mar 7, 2009 8:29am PST
    This is great info to have. I have electric heat in my house and its costing me a fortune. I can use any tips to save a few pennies.
    Report Abuse
  • Posted by dee Sat Mar 7, 2009 8:29am PST
    As far as letting batteries drain, that is a good thing to do. if you drain the battery all the way, you can actually use them longer. especially lap top batteries. if you keep them plugged in all the time, they loose their storage abilities.
    Report Abuse
  • Posted by VladimirM Sat Mar 7, 2009 8:31am PST
    I did always wonder how much money you could save by unplugging stuff like TV's, and computers.
    Report Abuse
  • Posted by Richard J Sat Mar 7, 2009 8:33am PST
    The lead in to this article asked "How much energy does unplugging electronics that are turned off really save?". Where is the answer to that question. It seems to me that yahoo does this a lot, they tease with one statement and then fail to answer. A waste of time.
    Report Abuse
  • Posted by U'll Never Know Sat Mar 7, 2009 8:33am PST
    Wow...
    Report Abuse
  • Posted by marksnews Sat Mar 7, 2009 8:34am PST
    I leave everything plugged in. I had a on/off switch on a monitor break and I had to replace the monitor. After that I happily pay the extra 10% for the convienence. I lessen my carbon footprint with most all other things. Hey you only live once!!!
    Report Abuse
  • Posted by Jim Sat Mar 7, 2009 8:34am PST
    Not all energy the device is using is wasted. Any energy a plugged in device uses while in standby is changed to heat. In the winter this heat helps to heat the house. This takes some load off of the central heating. In the summer the device will add to the air conditioning load.
    Report Abuse
  • Posted by tjg Sat Mar 7, 2009 8:36am PST
    hey peoples
    Report Abuse
  • Posted by skeet Sat Mar 7, 2009 8:36am PST
    My husband and I started turning everything off when we aren't using it. Especially computer and tv (we don't have cable). We also were better w/turning off lights and things. Our average savings per month has been $50 so it was well worth it for us.
    Report Abuse
  • Posted by joel Sat Mar 7, 2009 8:37am PST
    huh, theres a few minutes of time totally wasted.
    Report Abuse
  • Posted by RonaldG Sat Mar 7, 2009 8:38am PST
    OK
    Report Abuse
  • Posted by Doloris Sat Mar 7, 2009 8:38am PST
    You can drain your battery completely and charged it again full and it will last longer I still use my sell phone battery for the 6th year now and it stays cherced for 3 days approximately. The worst thing you can do is to charhed it when is not fully empty or not fully charge it and then use it.
    Report Abuse

Leave a Comment:

You must first sign in.

Green Picks Playlist