The Kill-A-Watt is a plug-in energy monitor that tells you how much electricity any given device is pulling down from the grid. You just plug it in between the outlet and whatever you want to monitor and it will tell you how much electricity is being used.  I recently wrote about a cool hack that the folks over at MAKE did that allowed their Kill-A-Watt to broadcast usage updates over the microblogging platform Twitter (follow me there).

Most of our homes are full of vampire gadgets — TV sets and radios, coffee pots and microwaves, cable boxes and modems, all of them sucking constant trickles of power, even when they are technically turned off. A small TV set can easily draw $30-50 a year in standby power, large plasma sets can cost you $165 a year on standby according to the US Department of Energy. That all adds up.

Multiply that by the roughly 116 million American homes, and you're looking at a whole lotta wasted energy and money.

The Kill-A-Watt is a great way to put numbers to your plugs — when you know how much energy is being wasted by any one device you're more likely to do something about it. One way to stop the drain is to put vampire devices on power strips that are turned off when not in use, cutting the power use to zero.

But you have to have a Kill-A-Watt to get started. They're not very expensive — under $30 — but you have to overcome inertia and order them off the Internet.

Unless you live in Maine. Residents of the Pine Tree State can now check out Kill o Watts from their local library. It all started last year when a Scarborough resident donated her Kill-A-Watt to the local library. Scarborough Public Library Director Nancy Crowell thought it was a great idea and worked with Efficiency Maine, a conservation program of the Maine Public Utility Commission, to get 600 monitors into the hands of 200 libraries around the state.

According to the Portland Press Herald, the Kill-A-Watt  have been very popular — 18 large libraries contacted by them reported that their devices are all checked out with waiting lists.

Every library in the country should be doing this. I'll keep my eyes open to other states picking up this program.

Click here to buy a Kill-A-Watt. When you're done tuning up your home, consider donating it to your local library.

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