Eliminating Phantom Loads

01/11/2013 by Daniel D. Chiras, PhD

Although very few of us know it, our homes are haunted. Not by ghosts, but by phantoms of another sort, known as phantom loads. Phantom loads come from electrical devices that draw power when they’re switched off. And they’re everywhere. Televisions, satellite receivers, DVD players, cordless phones, and stereo equipment all continue to consume electrical energy when switched off.

Battery chargers for a wide assortment of electronic devices, such as iPods, notebook computers, flashlights, chargeable drills, and even portable battery-powered vacuum cleaners are all phantom loads. (Even when the batteries are charged, they continue to draw power.)

That’s not all. Transformers for electronic keyboards, printers, fax machines, and small appliances such as coffeemakers also create household phantom loads. All of these devices, and many more, continue to draw power, night and day, when the devices are not in use.

Not all phantom loads are created equal, however. Some are quite high, others barely noticeable. Satellite receivers, for example, may consume 14 to 15 watts when operating, and 12 watts when not operating. Televisions may consume 30 to 60 watts when operating, but under one watt when shut off. Phantom loads also differ with respect to function. Some devices, like televisions, draw power when off to ensure the instant-on capability: when you press the power button on the TV or the remote, the TV turns on immediately.

Modems and satellite receivers for televisions provide the same benefit. Other phantom loads, created by devices like TiVo and programmable VCR and DVD recorders, are required to retain settings in memory for recording television programs. Others perform functions of more dubious value, such as the LED clocks on microwaves and coffeemakers. Still others, like battery chargers, continue to draw power if they’re plugged in, while performing no function whatsoever when the device being charged is not connected.

Although phantom loads are not always obvious—for example, cell phone chargers—others, like modems and routers, are quite conspicuous. The small red or green LED lights on these devices tell you the device is drawing power, even though it is not turned on. Together, though, the electrical consumption of the various phantom loads can add up—often substantially.

A simple way to cut down on power usage is to make sure your computer is set to an energy-efficient power-saving mode. Setting your computer to go into sleep mode when idle for a short time can save as much as $80 a year.

According to the U.S. Environmental Protection Agency, phantom loads account for about 40% of the total energy consumed by household electronic devices. In a home equipped with many electronic devices, especially a large screen television set, DVD players, computers, printers, and cordless phones, phantom loads could easily add up to 200 watts at any given time. That’s the equivalent of leaving two 100-watt lightbulbs running 24 hours a day, 365 days a year. If you pay 10 cents per kilowatt-hour, 200 watts of phantom load will cost about 48 cents a day, or nearly $175 per year.

Purging phantom loads is about as easy as it gets. But first you’ll need to locate them. As a general rule, any device that’s operated by a remote control or has a clock or a little red or green LED light that stays on all of the time draws power when shut off. Virtually all battery chargers and transformers also continue to consume energy when not in use if plugged into an electrical outlet.

To test for the not-so-obvious phantom loads, you could purchase a digital power meter with a clever name such as the “Kill A Watt” (about $30) or “Watts Up?” (about $110 to $140) meters. (Both can be found on the Internet.) Although they’re helpful, it’s probably not worth investing in one of these meters just to check for phantom loads. Using the guidelines just mentioned, you can pretty much locate all significant phantom loads in your home.

These meters, however, are helpful for home energy audits; they’re plugged into outlets next to appliances or electronic devices that you want to test. The device or appliance is then plugged into the socket in the meter. If the meter indicates power usage when the device you’re testing is switched off, it is a phantom load. The meter also shows the size of the phantom load in watts and amps.

Once you’ve identified phantom loads, it’s time to eliminate them. Strategies vary by device, and some phantom loads should not be eliminated. For battery chargers used with personal electronic devices, such as cell phones, digital cameras, and laptop computers, and transformers for electronic keyboards, the best way to eliminate the phantom loads is to unplug the chargers from the electrical outlet when they’re not in use.

When you’re done charging your cell phone or digital camera, for example, unplug the charger from the wall. You may also want to purchase a solar battery charger for such devices. For televisions, stereos, desktop computers, printers, modems/routers, and satellite tuner boxes, it’s best to plug the devices into a power strip. When you turn off these devices, also turn off the power strip to terminate the flow of electricity to them. These devices can also be plugged into outlets that are controlled by wall switches.

Electronic devices, such as microwaves, can be controlled by installing a “switch-and-receptacle.” This is an electrical outlet that’s controlled by its own on-off switch. When the switch is turned off, the flow of electricity to the plug is terminated. Any device plugged into the outlet is therefore turned off.

Switch-and-receptacles are available in hardware stores and home improvement centers. They’re easy to install, if you’re experienced and capable in electrical wiring. If not, it’s best to hire a licensed electrician. The circuit will need to be turned off (and tested with a voltmeter to make sure it’s off) before disconnecting the electrical outlet and installing the switch and receptacle.

While it’s easy to eliminate phantom loads, it’s not always a good idea. If you record TV programs, completely switching off the VCR or TiVo will erase your settings. Garage door openers require a small input of electricity for the remote control, so it’s best to leave the power on unless you’ll be away for several days. I switch mine off (at the breaker box) at night and when leaving home. (Check with your garage door opener manufacturer to ensure safe practices.)

In many newer homes, smoke detectors and burglar alarms are hard-wired—connected to the electrical wiring in your home. While these devices will operate on backup battery power alone, the electrical connection is required by building codes and should not be disconnected.

Although some phantom loads can’t be eliminated completely, they can be reduced by use of Energy Star-appliances, whose phantom loads are 50% less than other models.

Eliminating phantom loads costs very little—or nothing—if electronic devices can be plugged into existing electrical outlets with wall switches or power strips, or if you just unplug them. With very little effort, you can easily cut phantom loads by half. The purchase of a power strip can pay for itself in less than a year if you plug your television and stereo system into it and turn it off when these devices are not in use.

Phantom loads are often individually small, but add up to about 5% of a household’s overall electrical demand. If your family uses 800 kilowatt-hours of electricity per month (roughly the national average), phantom loads in your home come to about 40 kWh, or about $4 per month, or $48 per year. In many homes, however, with entertainment centers, numerous TVs and satellite receivers, and computers, phantom loads can be much higher—easily 200 watts. In such homes, phantom loads will cost a lot more—about $250 per year. Nationwide, it’s estimated that phantom loads cost Americans more than $4 billion a year.

To calculate your savings, collect your utility bills for the past year and add up the electrical usage. It’s listed in kilowatt-hours. Now multiply this amount by 5%. If you cut phantom loads by half, divide this number by two and then multiply the savings by your electrical rate to determine your savings.

Adapted from Green Home Improvement, by Daniel D. Chiras, PhD, available through RSMeans