It's hard to avoid wasting a little energy here and there. But everyone can take a bite out of energy-wasting, money-sucking vampires in their homes.

These vampires are gadgets and appliances that use power even when they're turned off -- running up your utility bill and generating unnecessary carbon dioxide at the electricity plant.

For my hunt, I included devices that my husband and I could turn off but that we tend to leave on or in sleep mode when we aren't using them. The

Cornell University Cooperative Extension estimates that the typical home has about 20 true vampires lurking around. Most are home electronics or portable gadgets that need to be recharged. The

Energy Department estimates that home electronics consume 75% of the total juice they use while they're turned off.

Here's how I attempted to ferret out these creatures:


Terrapass blog points out that if items such as chargers feel warm even when nothing is attached to them, they're probably wasting power. But a more high-tech way to go about vampire-slaying is with a

Kill-A-Watt EZ, an electricity usage calculator that you can buy online for around $60.

I tested a Kill-A-Watt and found it pretty easy to use. I typed in the amount I pay per kilowatt-hour for electricity (I got the rate from my bill), then plugged the Kill-A-Watt into a wall and plugged various devices into it to get projections for how much each one costs to run on a daily, weekly, monthly and yearly basis. I could also leave a device plugged into it to keep a running tally of actual electricity consumption.

At first, it wasn't generating any numbers that seemed particularly impressive. My iPod charger didn't use enough electricity to register a reading when it wasn't actually recharging. The base for a

General Electric

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cordless phone nibbled a mere 20 cents a month, and two


cellphone chargers wasted electricity at a rate of about 80 cents a month combined when attached to fully charged phones.

But then I went through two home offices testing PCs, laptops and peripherals such as printers, routers and cable modems, and headed to the den to test the TV, DVD player and set-top box.

That's when things started to add up.

My true vampires, the devices that use power even when they aren't in use, ran up charges at a rate of more than $10 a month, or 13% of our average $80 electric bill -- not as bad as I feared, but still, that's $120 a year I could put to other use. Far scarier was the tally for those devices we leave plugged in, turned on or on standby when we don't need to: nearly $46 or 57% of our electric bill.


Some of the biggest culprits overall included a cable box made by Scientific Atlanta, a unit of


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, which uses the same amount of electricity whether it's on or off; the


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TV, which guzzles power at a rate of $12.29 a month when we leave it on standby; and a Goldstar DVD player that uses half as much power when it's turned off as it does when we're actually watching a DVD.

In one of two home offices, a

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printer burns electricity at a rate of $1.61 a month when left on 24-7 and uses 88% as much power turned off.

And sad to say, my sexy new iMac desktop from


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would cost $13.30 a month if I left on all the time and $11.28 -- nearly as much -- in sleep mode. An older Apple laptop has a much more cost-efficient sleep mode. But when it is turned off, it costs the same 60 cents a month to leave it plugged in whether it is recharging or fully charged.

In the other home office, things are worse. A Windows-based computer still has a separate monitor and CPU, allowing us to leave the computer on all the time with the monitor on standby. This little convenience costs $14.50 a month. And we can tack on another $4.83 for the


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laptop we leave in standby mode when we aren't using it.

So how can you slay such vampires in your own home?

If you'd like a high-tech solution, consider a

wholehouse switch, which has been the subject of discussion and more than one blog entry at

You can position the switch near your front door, where it communicates wirelessly with the light switches and outlets you'd like to turn off completely when you leave home or go to bed at night. So you can power down your whole TV room or home office but leave your refrigerator and answering machine on.

At a cost of more than $1,100, you would have to save $46 a month on your electric bill to have it pay for itself in two years ($30 a month if you want to give it three years). But if you have a lot of gadgets or a sizable house that often sits empty, maybe because you travel a lot or you split your time between a primary and weekend residence, it might be worth it.

For a lower-tech and lower-cost approach, do what my husband and I did: We've taken our Linksys router and



cable modem, which cost $2.61 a month combined when left running perpetually, and put them on a power strip that we turn off when we go away. We'll do the same for the TV, DVD and cable box -- and no more leaving the TV on standby.

Turning off the power strips in our home offices when we go away can't hurt either. More important, we'll be turning off our computers and printers at night. And we won't leave our cell-phones and laptops dangling on their power cords for hours after they're recharged.

Eileen P. Gunn writes about the business of life and is the author of "Your Career Is An Extreme Sport." You can learn more about her at

her Web site.