Fluffy the Vampire Slayer

"I should get the vacuum cleaner out more often," I said to myself as I chased the fluffy dust bunnies from their nest of cables beneath the desk.

Although ... where would I plug it in? Only one of the numerous multiway extension leads had any free sockets -- and it had no power. I suspected it was plugged into itself, but I didn't have the courage to disentangle all the wires to find out.

Besides, that day I had another mission: slaying vampires.

"Vampire" electrical devices account for 4.4 percent of all electricity consumption, according to the German Federal Office for Environment Protection (Umweltbundesamt, or UBA), or 10 percent of home electricity consumption, according to the U.S. Department of Energy's Berkeley Lab. These "undead" gadgets are neither alive (turned on and doing something useful) nor dead (turned completely off). Instead, they are "on standby" and continue to draw electricity while doing nothing, just in case their owners wish to, say, play a DVD at a moment's notice, or recharge their cell phones without bending down to plug the charger into the wall socket.

Many governments have passed legislation or set targets in recent years to reduce the power consumption of devices on standby to 1 watt or below.

Even if a device draws as little as 1 watt of power while on standby, the cost mounts up: In a year, it would use 8.76kWh of electricity, which in France costs roughly €1 (US$1.25). Turn off devices that together consume 100W in standby mode, and you've saved €100!

To find out how much a device costs to run a watt-meter is essential, as not all manufacturers publish figures for how much power their devices draw in standby mode -- and for those that do publish figures, it doesn't hurt to check their claims.

Buying yet another gadget to measure how much power the others are consuming would have been a waste, though: That's why I borrowed a watt-meter from a friend. If you live in Germany you don't need energy-conscious friends as you can borrow a watt-meter free through a nationwide program promoted by the UBA. At a more local level, similar projects exist in Ontario, Canada, and in the U.S. state of Maine, often operated through public libraries. Ask around: There may be another one near you.

Once you've got hold of a watt-meter, the fun starts, as you slip it between various devices and the wall outlet, turning them off and on to see how their power consumption changes.

First up was our microwave oven. People are often reluctant to unplug these because they would have to reset the clock each time, but ours doesn't have an electronic timer, just a sort of clockwork knob that spins round till the cooking time expires, and once it goes "ping" (no strident electronic siren), it's really off. Verdict: No need to unplug this one. I couldn't test the conventional oven, which does have a clock, because in France devices that draw over 3.5kW have a special plug that the watt-meter wouldn't fit.

Next stop was the living room. After a few minutes disturbing the dust bunnies, I eventually identified the plug belonging to our DVD player. Running, the meter said it consumed 15W, just as the instruction manual predicted -- but what the manual didn't tell me was that on standby (the mode it goes into when you press the front-panel button labeled "on/off"), the player would still consume 10W. That's a lot of power to light up one tiny red LED!

While groveling around behind the hi-fi stack, though, I made two amazing discoveries: first, the DVD player has a real on-off switch hidden around the back that makes a satisfying click and cuts the power consumption to zero (a €10 annual saving!), and second, turning that switch off finally solved the mystery of the irritating interference we'd been getting on FM and AM radio.

Our DSL modem and wireless router consumed a little over 30W between them, and almost the same in standby mode. Since we're only using them for a few hours in the evening, it makes sense to turn those off altogether -- an annual saving of €25.

I didn't have time to test all our power adapters and mobile-phone chargers, as my friend wanted his meter back for another energy-saving project, but the experience was eye-opening.

However, it's not always completely wasteful to leave a power adapter plugged in or the bathroom light on all night (or so I tell my other half). That "wasted" electricity just serves to warm up the apartment -- and since ours has electric heating, the energy would have been used anyway, whether by the lamp or the heater.

As spring approaches and the days lengthen, though, we'll have no need for extra heating or lighting when we get up in the morning. I'll have to change my habits -- and the watt-meter has given me some ideas for where to start.

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