Unlike the guy in your building who likes to talk about how his Amiga was better than any computer sold today, AT&T's new Zero cell-phone charger knows when to stop.
Unlike conventional chargers, the Zero won't draw power if there's no phone plugged into it. AT&T claims the Zero, which it developed with phone accessory vendor Superior Communications, is the first such charger on the market. It will go on sale only at AT&T stores across the U.S. in May, and interested customers can sign up to be notified when it's released.
AT&T wouldn't specify which phones the Zero charger will be able to charge, though spokesman Mark Siegel said it was designed for the carrier's major smartphones. But its USB interface suggests it will be compatible with the Apple iPhone.
Most device chargers keep drawing power from the electrical grid even when there's no device plugged into them. They are among the "vampire" devices that consume energy even while in "standby" mode when they are not being used. The U.S. Department of Energy estimates that standby power makes up as much as 20 percent of home energy use in the U.S.
In addition to saving power in the wall socket, the Zero charger can help save the environment because it will work with many different devices, so there is less need to buy multiple chargers, according to AT&T. The charger will cost about the same as current replacement chargers offered by AT&T. The carrier lists several small travel chargers on its Web site that are priced at US$29.99, or $20.99 with a $9 online discount.
It's rare for standby power to make up 20 percent of a home's energy consumption, but the average household may spend $40 per year on it, said Michael Kanellos, a senior analyst at GreenTech Media. And across hundreds of millions of homes, that small amount of electricity taken from the power grid adds up.
"It's power being generated but not doing anything productive, so you might as well get rid of it," Kanellos said.
The Zero charger is a step in the right direction, while other companies are working on even smarter chargers, he said. Those will stop drawing power as soon as the phone is fully charged.