Stop power leaks; smile at savings

As I leave the house in the morning, I take a quick look around to make sure I've turned everything off - the stove, the TV, various computers. Of course, they're all still running.

The stove has a clock in it. The TV's remote control sensor never sleeps, and the cable box keeps downloading new program listings. The computers, too, remain partially powered up, even if I hit the "off" button.

It all costs money. The US Department of Energy estimates that about 10 percent of the juice used by the average household is consumed by idle devices - up to 40 such gadgets in an average home, according to the feds.

The average US household spent $95 a month on electricity in 2006, again according to government data. Stifling all these power leaks could save about $110 a year - a handy sum, though hardly a fortune.

And to help save money on your power-hungry gadgets, a number of companies will gladly sell you still more gadgets.

For instance, there's P3 International Corp.'s Kill A Watt, a user-friendly electric meter that allows you to figure out exactly how much power an electrical device uses. The Kill A Watt comes in a cheap version that requires the user to do some grade-school arithmetic to calculate power costs. It's available online for as little as $20. Or for about $35, there's the Kill A Watt EZ, which does all the math.

Both work on the same basic principle. Plug the Kill A Watt into a power outlet, then plug your device into the Kill A Watt. It measures the amount of electricity the gadget draws at any given moment. More important, it will measure power usage in kilowatt-hours, the method used by the electric company as it writes up your bill. Next, multiply a device's kilowatt-hours by the rate charged by your utility - it's on the electric bill. At my house, it's 12.6 cents. Armed with Kill A Watt, I found that my favorite PC, with monitor, laser printer, and amplified stereo speakers, would use up $204 per year in electricity if left running 24 hours a day. But I turn them off when unused, so they're actually running about eight hours a day, for a cost of about $68 a year.

I also found that my backup Linux computer consumes 2 watts of power even when shut down. Most computers are shut down through a software command, rather than a physical switch. This puts the computer in a "soft off" state, with a low level of power still flowing to the motherboard. As a result, I'm paying $2.75 a year in power costs on my Linux box just to keep it plugged in. That won't break the bank, but consider that there are a few hundred million machines in the United States running up the same tab.

Kill A Watt's an informative little device, and yet you can get by without it. The federally funded Lawrence Berkeley National Laboratory publishes a heap of data about the power consumption of various home appliances and digital devices. While not as precise as doing your own measurements, this data provide a good idea of your gadgets' thirst for power. Start doing your homework at standby.lbl.gov/standby.html.

Once you've identified the power wastrels in your home, you could unplug them after each use. But it's easier to plug them into a cheap power strip, the kind with an on-off switch. At one stroke you can really power down anything plugged into the strip.

But there are some devices you don't want to switch off. Yes, shut down the TV when you're at work, but you want your digital video recorder powered up for the next episode of "General Hospital." So you might need two power strips, with one devoted to gadgets that must remain powered on.

The power strips themselves have gotten smarter. Monster Cable Inc.'s MDP 900, for instance, is tailored for computer users. One of the jacks is set aside for the computer, with others dedicated to peripheral devices - the monitor, printer, and speakers. The MDP 900 detects when the computer is switched off, or when it goes into sleep or standby mode. When that happens, it shuts off power to the peripherals. Reactivate the computer, and the other devices start up as well.

It's a lovely gadget with a lunatic list price of $130 - enough to eat up any energy savings it might deliver. Sure, you can find the MDP 900 online for about $70, but why bother? Instead, hunt up American Power Conversion Corp.'s P7GT surge protector, available online for $20 to $35. It has just seven power outlets to Monster's 10, and lacks other Monster extras like a pair of ports for charging USB devices. But it has the same power-saving feature as the MDP 900, at a price low enough to actually save you some money.

But not much - $100 or so per year, tops. Which is why most people will keep right on pretending that off really means off.

Hiawatha Bray can be reached at bray@globe.com.