The hidden power of ‘sleep’ mode

Warren Swil is a journalism instructor at Pasadena City College.

Have you recently awoken in the dead of night to find a greenish blue haze swirling around your home, even though you turned off all the lights before going to bed?

It’s not the ghost of Aunt Betsy returning to haunt you. Most likely it is the rapidly increasing plethora of tiny light-emitting diodes featured on modern electronic appliances, many of which indicate that a machine is in “standby” mode. In fact, it’s probably been years since you really turned “off” your desktop computer or, for that matter, your television.

Most modern electronics come equipped with either standby or “sleep” functions. First made widely available on computers and TVs, this state of limbo was created to avoid time-consuming waits when machines start up. We’ve all spent dozens of hours cumulatively waiting after we push the start button as our computers read and load all the programming code necessary to get ready. In the era of vacuum tubes, it took televisions several minutes before the picture became visible.


In standby, a machine is not really turned off. It goes into a state of reduced activity that requires only minimal power consumption. The downside is that even at vastly reduced power levels, millions of machines running all day, every day adds up to huge amounts of wasted energy. With oil prices at record highs and the climate under threat from excessive consumption of fossil fuels, this is neither smart nor desirable.

It’s not the tiny lights themselves that are at fault -- they’re a marvelous, energy-saving invention. Rather, it’s what they indicate: a seemingly unstoppable proliferation of devices that siphon power even while not in use.

A new-model Braun razor features not one but three LEDs as part of its self-cleaning system. Two lights are green, one blue. “Keep it plugged in,” the instructions say.

It’s the same for office equipment. Count the little lights on your desk at home. A new DSL modem has six green LEDs, five of which are always on when the machine is plugged in. A copier/fax/printer (which must always be on to receive faxes day or night) has two green ones. The computer monitor may have a blue one. There’s a green LED on every computer speaker, a red one on the radio dial. And that’s not counting the green clocks on the microwave and coffee maker.

Not surprisingly, some people are becoming concerned by this trend.

In June 2005, British Environment Minister Elliot Morley reported that electrical equipment in sleep mode used enough energy per year to emit about 800,000 tons of carbon. That’s just for the 60 million or so Britons; multiply by five for the United States. The U.S. Department of Energy has estimated that by 2010, the portion of each utility customer’s bill consumed by appliances in standby mode will reach 20%.

Do an inventory in your home and you will be shocked.

“They’re the little red-eyed monsters that silently suck up energy, leaching electricity via vampire fangs gripping power sockets,” wrote Steve Dow in the Sydney Morning Herald last month. Dow had a consultant check his home, where just a TV, DVD player, stereo, computer, modem, wireless router and microwave were left in standby mode. He was astonished by the result: “Bypassing standby or sleep mode and switching appliances off at the power point, where practical, would cut our power use by 10%.”


A 10% reduction in California’s 254 annual megawatt hours would save roughly as much energy as is consumed by South Dakota, Vermont, Alaska and Rhode Island combined, according to the Department of Energy.

In January 2006, California mandated maximum levels of standby power consumption for some -- not all -- household electronics. But the big step will come when consumers become convinced that it’s worth trading convenience for conservation.

So next time you awaken in the middle of the night, check around to see if you are bathed in an eerie, greenish-blue hue. And remember, those innocent-looking, sometimes blinking little monsters are sucking the money out of your wallet as you sleep.

Sweet dreams.