What are Energy Vampires (and how do you kill them?) - Furnace Compare

We’re under increasing pressure to stay connected at all times. As a result, the ability to start faster and stay online is becoming a feature in many of today’s electronics. Some electronics still consume power even when they’re turned off. Others consume energy while providing secondary functionality unrelated to their primary responsibilities. Such appliances and electronics are called energy vampires or power vampires, and they’re becoming more and more common.

What Is an Energy Vampire?

Simply stated, an energy vampire is any electronic that still consumes power even when it has been turned off. The power used is called “standby power” or “phantom load”. The feature allows modern appliances to accomplish a bunch of neat tricks. It allows a remote to turn on your TV. It helps your cable box update your TV guide. It helps your electronics keep the time.

Some of the most common energy vampires are computer equipment, television sets, stereo and speaker systems, cable or satellite boxes, and pretty much anything with a clock in it.

Calculating the Cost of Standby Features

Estimates from Energy.gov suggest that standby power accounts for anywhere from 10 to 13 percent of the total amount of power used in the US and Europe. In real dollars, the average family in the United States could be paying as much as $100 a year to cover the costs of the phantom load.

A recent study by the NRDC suggested that power vampires cost the United States as much as $19 billion a year. Over the given lifetime of a microwave, for example, it may consume more power when not in use than it does while working.

To calculate the annual cost of an energy vampire, you need to know a few pieces of information:

  • An estimate of the standby power consumed by that device
  • An estimate of the amount of time that the device remains in standby mode
  • Your electrical cost per kilowatt hour (kWh)

For example, let’s imagine you wanted to know how much you spend on standby power for your cable box / DVR. (Many of these devices consume dramatic amounts of power even when you are not watching TV).

Standby power estimate: You can use a tool called an energy use monitor to get a good estimate of the standby power used by an appliance. While professional models cost hundreds of dollars, consumer versions start at less than $20.

Simply plug the appliance you want to test into the monitor, and then plug the monitor into the wall. The monitor measures the electricity drawn by the appliance. Let’s imagine that our monitor gave us a reading of 48 watts per hour in standby mode. Dividing that value by 1000 gives us the standby power in killowatts: 48/1000 = .048 kw.

Time in standby mode: You’ll need to estimate how much time the device is not being used each day. For example, in the case of your cable box, if you think you watch about 3 hours of TV on average each day, the device would spend 21 hours per day on standby. 21 hours per day multiplied by 365 days per year would give you a product of about 7,665 hours per year on standby.

Cost per kilowatt hour: Your electric bill is the best place to find this information. In Feb. of 2017 the US Energy Information Administration reported that the average cost of residential electricity in the US was $.1282 per killowatt hour.

Calculations: Now, you can simply multiply the standby power of .048 kw per hour by 7,665 hours to determine the total load: 367.92 kwh. Multiply that by the cost per kilowatt hour to get a total cost for the year: 367.92 x $.1282 = $47.17.

If you’d like a shortcut to this method, you could checkout this phantom load calculator.

Standby Power in Your Furnace and Air Conditioning

The use of standby power in electronics isn’t just limited to your cable box and the like; your furnace and air conditioning unit can also be siphoning electricity, even when you’re not using them on a regular basis.

Air Conditioners

In order for your air conditioning unit to switch on at a moment’s notice, it needs to draw power. Some models of air conditioner can draw as much as 50W in standby power, even when you’re not using them regularly.


Similarly to air conditioning units, furnaces need the ability to turn on the moment you need them to heat your home. Even in July, some furnaces still pull around 40W to stay prepped for duty.

How Can I Cut Down on Wasted Energy?

Here are a few easy ways to help reduce energy waste:

  • Unplug: The simplest way to stop a potential power vampire from drawing electricity is to simply unplug it. When you’re not using your computer, unplug it and then simply endure the two minutes it takes to boot up in the morning.
  • Turn Stuff Off: It might be tempting to pause your game while you go handle some mundane chore, or simply leave your computer up and running while you go have dinner with the family. Turn the console off. Put your computer in sleep mode.
  • Set Specified Downtime: Devices like Wi-Fi routers are always consuming power. However, many modern routers allow you to set hours of use. Setting these hours can teach your router to shut down automatically every night between bedtime and morning.
  • Buy a Power Strip with Switches: If you’re not in the mood to unplug every one of your electronics every time you’re done using it for the time being, then buy a power strip with a switch on it. This allows you to power down several devices simultaneously with the flip of a single switch.
  • Do Your Homework: Every product is different. That being said, many devices have built-in features designed to help you save power. Simply leaf through the owner’s manual or check out the company’s web site to find specifics.

Making the Right Choices With Your Electronics

In addition to reducing the amount of electricity used by the devices you already own, you should consider standby power when buying new devices.

Energy Star certified products can be found in many different product categories and are designed to use considerably less standby power than non-certified alternatives. When you’re researching your next big home electronics purchase, remember the cost associated with a power vampire. You could be saving yourself a whole lot of money in the long term.

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