Vampire hunters: Devices reduce energy waste
- — 26 August, 2010 10:47
It's 1 a.m., and everyone in the house is asleep. The television is off. The computers are off. Your cell phones and MP3 players are plugged in but no longer charging. And all these products are still sucking electricity.
"Vampire power," also known as "phantom power," accounts for a surprising amount of U.S. electricity consumption. According to a Lawrence Berkeley National Laboratory report, "A typical American home has forty products constantly drawing power. Together these amount to almost 10 percent of residential electricity use." (For more about how organizations can manage their power consumption, see "Save Serious Money With a Business Energy Audit.")
What sort of devices suck electricity even when they're off? Chargers and AC adapters are notorious vampires, continuing to pull electricity even when the product they're attached to doesn't need it, or even when they're not attached to anything but the wall. Some products, such as a desktop PC, consume about 5 watts even when turned off and merely plugged in.
To slay vampire-power suckers, people are turning to a new class of surge protectors and rechargers. I looked at several of these products--and unfortunately, I found their usefulness limited. Trying them, however, beats running around your house every night yanking plugs from the walls before hitting the sack.
When used correctly, green surge protectors cut off power to devices that don't need it. One of the outlets on such protectors is designated the control outlet; when the wattage on that outlet drops below a certain level, the surge protector kills the power going to several of the remaining outlets. Other, always-on outlets continue to receive power.
The protectors make sense in an arrangement where one central device dominates the others, such as the computer in your office or the TV in your home theater. You're not likely to need your monitor if your PC is off, or your DVD player when your TV is off.
The always-on outlets are for devices that must be on at all times, such as a router or a DVR.
I tried three surge protectors--the Belkin Conserve Smart AV, the HP Monster Digital PowerCenter 800G, and the TrickleStar PC TrickleStrip--and all worked as advertised.
But while the concept is good, the devices don't cover everything. For instance, my Dish Network DVR needs to remain on, and it burns a frightening 53 watts in standby mode. A DVR in standby mode refreshes the program-guide data, downloads software, monitors the satellite for changes to channel lineups, and stands ready to record at any time.
Even so, a green surge protector cuts usage in my home theater by about 22 watts when the TV is off, for a savings of 14,000 watt-hours a month. (Those figures assume that the TV is on 3 hours a day.)
Of the models I tried, only the HP Monster was large enough to accept huge, space-wasting AC adapters, also known as wall warts, in each of its eight outlets (three switched, four always-on, and the control). It has a 3140-joule rating, promising substantial protection against electricity spikes. It also offers telephone, ethernet, and coaxial cable protection. On the other hand, at a street price of US$80, it's by far the most expensive of the three.
Another problem with the Monster: It pulls about 1.6 watts with nothing plugged into it--at least in part because of its unusually large, pretty, but useless LEDs. That made it a bit of a power vampire itself.
The $30 (list price) Belkin Conserve Smart AV is the Monster's opposite. You can't plug an oversize wall wart into any of its eight outlets (five switched, two always-on, and the control) without blocking at least one other outlet. It doesn't protect phone, ethernet, or coaxial cables. It has a reasonable but unspectacular 1080-joule rating. With nothing plugged into it, the Conserve Smart AV drew so little power that the meter I used, a Watts Up Pro, indicated it was consuming none at all.
The $40 (street price) TrickleStar PC TrickleStrip offers fewer outlets than the others, only six (three switched, two always-on, and the control). The always-on outlets are spaced apart from each other, making one of them wall-wart-friendly. It can protect a phone connection, but not ethernet or coaxial (a very similar TV TrickleStrip handles coaxial but not phone). It protects your equipment up to 2160 joules. With nothing plugged into it, the device barely registered on my Watts Up Pro, going back and forth from 0.0 to 0.1 watt--not as impressive as the Belkin, but close.
One issue you shouldn't worry about is the power threshold, the point at which the protector shuts off or turns on the switched outlets. The Monster has fixed thresholds, the Belkin uses "intelligent chips," and the TrickleStar lets you set the threshold. In my tests, all three handled the job perfectly. The difference between what a PC or TV burns when it's on and when it's off is so great that any reasonable guess will be sufficient.
We live in a world of battery chargers and AC adapters (which are also quite often battery chargers). And the main problem with these power bricks, wall warts, and easy-to-lose pocket chargers is that they don't know when to stop.
When the device attached to them needs power, they provide it. When the device is entirely charged or turned off, they still give it juice, although not as much. And even when the device is removed, the plugged-in adapter or charger continues to draw a bit of electricity. Keep enough of these vampires plugged into wall sockets 24/7, and the amount you waste can add up.
A smart charger knows when it's needed and shuts down when it isn't.
Since it's impossible to create a smart charger that can support countless numbers of devices (each of which came with its own unique AC adapter), they tend to support the two most common standards: USB and the iPod/iPhone connector. Of course, since you can charge an iPod or iPhone from a USB port, only one standard really needs to be supported.
But iPods, iPhones, and USB-chargeable devices are not really the problem. They're already at least somewhat smart about power. I tested four USB-chargeable devices--a Samsung Omnia smartphone, an iPod Classic, a Creative Zen MP3 player, and a Samsung YP-Q2 MP3 player--without a smart charger, to see how much they waste after a charge is complete. With all four, the trickles (if there were any) were so small that my Watts Up Pro said they were using no power at all.
I can't tell you with absolute certainty that the smart chargers I looked at can accurately cut your power usage. I can say, however, that if you don't keep multiple chargers plugged in round the clock, they won't save you much.
I looked at three chargers--Belkin's Conserve Valet, and the iPod and mini-USB versions of the Ventev EcoCharge--although two of them were essentially identical.
Whether it saves power or not, the $17 Ventev EcoCharge makes a handy little portable charger. It fits easily in the palm of your hand, and plugs into an outlet without crowding other devices. The 62-inch cord ends in a mini-USB, micro-USB, or iPod connector, depending on the model you buy. An LED light tells you when it's finished charging.
The device also has a hidden USB port, which allows you to power any USB-chargeable device in addition to the one you bought the charger for.
The $40 Belkin Conserve Valet (not yet available as I write this) takes a different approach. It's a station, basically a 9-by-6-inch platform with four USB ports. You plug cables into the ports (the plugs can be standard USB on both sides, or special ones like USB iPod connectors), wind excess cable around the Valet's inside, and plug the Valet into a wall socket.
When you want to charge something, you plug it into the appropriate USB cable and then press the Valet's on button. When the LED light stops glowing, your device is charged. It's a convenient way to charge your devices, assuming you charge them only in one particular location.
These surge protectors and chargers can help you cut your power bill, but don't expect miracles. In fact, conventional surge protectors, placed where you can easily reach the power switch, will save you even more--provided that you cultivate a few good habits.