You turn lights off when you leave the room, you turn off your computer when you’re not using it, but your power bill still looks like you leave the proverbial lights on all day and night. The culprit is likely sitting silently under your shiny HDTV set.

Dear HTG,

Lately I’ve been paying more attention to my power bill in an attempt to be a bit more ecologically minded (and save some money too). Although I’ve done various things like switch out my high use light fixtures to LED bulbs and been more conscious in general of how I’m using electricity, my bill hasn’t dropped quite as much as I’d expect.

I mentioned this to a neighbor in passing the other day, and he said it’s probably my cable boxes as he’d heard they were huge power sinks. This seems a bit strange to me as they just don’t look like a piece of equipment that would consume a lot of power… but what do I know? Is he right? If he is, why do cable boxes consume so much power?

I have four cable boxes in my house plus a DVR supplied by my cable company in the living room.  How much power are they consuming? Is there anyway to get definitive answer?


Cable Curious

You have several great questions in your email. Let’s start with the easiest to answer and move to the hardest. Along the way we’ll provide some tips to help you get to the bottom of your problem with the definitiveness you’re after.

Cable Boxes Are Hungry Energy Vampires

First, your neighbor is right. Cable boxes and DVRs are shamefully power inefficient. A 2011 study by the National Resources Defense Council (NRDC) found that cable boxes and DVRs were so staggeringly power hungry that, based on the estimate number of these units in the United States the net power bill for all the cable boxes and DVRs across the country was roughly 3 billion dollars (2 billion of which was wasted on the approximately 16 hours a day the devices sat idle).

Their findings indicated that power consumption of  the average cable box/DVR combo (~446 kWh/year) was higher the average refrigerator (~415 kWh/year) and was second only to air conditioning units (1500+ kWh/year) in terms of highest power use in the typical household.

Despite the fact that this information was widely published around the time of the study and other studies (and consumer experimentation at home) proved that the cable and DVR boxes were very power hungry, little has changed in the intervening years. While cable companies and the electronics firms that supply them with hardware could work toward Energy Star certification and lower power use most of them have no interest in doing this. This leads us to your second question focused on why cable boxes consume so much power.

Instant Use Means Always On

Televisions have always been, save for the earliest tube televisions that actually needed to warm up for a moment, an always on instant-gratification device. Use any television from the last 30 years and you’ll get the same experience: press the power button on the remote and the TV flicks immediately to life.

Consumers expect this and cable boxes are designed to provide this. Unlike computers, where the consumer has some expectation that they will have to wait for a small window of time after the device is turned on, televisions are expected to turn on immediately. As such, companies designed cable boxes to be always on and to be ready to respond to user commands with zero delay. The majority of cable boxes on the market never idle, never hibernate, and never go into any sort of power saving state. It’s essentially the equivalent of running a computer 24/7 so that someone can sit down at any moment, turn the monitor on, and start surfing the web.

DVRs are even bigger culprits when it comes to energy consumption because not only do they have all the overhead trappings of the cable box but they also include one or more hard drives to store the recorded media. It’s a rare DVR unit that has any sort of power saving feature or even spins the hard drives down when not in use. So now in addition to the power consumption of the cable box you also have what amounts to a miniature Network Attached Storage (NAS) unit running 24/7 under your television.

How to Measure Your Boxes Energy Use

Your third question focuses on how much energy your boxes are using. Without actually measuring your boxes there’s no way to give you a perfectly definitive answer but we can move from a general estimate to a more precise answer.

You indicated that you have four cable boxes and one DVR. The previously cited study found that HD cable boxes averaged 171 kWh/year and HD DVRs averaged 275 kWh/year. Assuming you have units that perform around the same as the average of the units tested in their study that means your annual household energy consumption for your media devices is approximately 959 kWh/year. Or, to put that in perspective, a value equivalent to putting two full size beer fridges in your garage (and then leaving the garage lights on 24/7 just in case you need to get a beer at 3AM).

You can further refine this estimate by searching for your specific cable box and DVR model numbers to see if there are any formally or informally published energy use results. While this will be more accurate than guesstimating based off the averages found in the NRDC study there’s another kink in our power estimation plans. Different boxes deployed by different cable companies can have significantly different power usage patterns. Some cable boxes don’t even have standby modes or any sort of power efficiencies built in. Some cable boxes do, but the providers program them to ignore standby modes because they don’t want consumers complaining about waiting 10 seconds for the cable to come on. Other cable companies have their programming guides set up to update frequently and prefer the box to stay on for ease of updating and such.Ultimately the majority of companies have favored passing the expense of the box completely along to you and have opted to keep them up and running 24/7 to provide a snappy user experience, updated guides, and to minimize user complaints.

RELATED: The How-To Geek Guide to Measuring Your Energy Use

In light of all that, the only real way to get a definitive answer on your power use is to measure the actual devices in your home. Fortunately doing so is really simple (provided you don’t mind spending around $20 on a very handy energy measuring tool). We’ve written an easy to follow guide to measuring your home energy use; the guide works whether you’re trying to figure out the power use on your computer, fridge, or cable box.

Follow the guide, use the handy Kill-a-Watt meter , and you’ll have a very precise answer after leaving the device to measure power use for a day or two.

What Can You Do?

One question you didn’t ask, but that we’re going to add to the list, is “What can I do about it?”

If you had your cable set up in the last year (or received new cable boxes) there isn’t, unfortunately, a whole lot you can do if you find that your cable boxes and DVR are insanely power hungry. Generally speaking cable boxes come in one or two models per company and you get what you get. That said, we would encourage you to contact your cable company and make it known that you want an energy efficient box. Whether or not they’ll have one (or settings to adjust on the one you have now) is unlikely but at least there will be noise on the line indicating people want them.

Barring getting a more efficient box, which is unfortunately unlikely, you can experiment with managing your power use. The savings here are highly variable and you (and everyone reading this Ask HTG article) will need to test their own system to see what works best. Here are a couple potential ideas to get you started in experimenting with your cable boxes.

In multi-box households, especially those households that have newer cable box/DVR setups where the main box/DVR acts as a central client and the other boxes in the house act like thin clients, will likely benefit from putting the lesser used boxes on either timers or switches. The primary box, especially if you have a DVR, will need to stay on to communicate with the cable company and pass shows along to the DVR but the secondary boxes will likely communicate with the main box and thus not take as long to boot up when you do use them.

If you don’t watch television late at night or at all during the day while you’re at work, you could also set up an appliance timer to turn the box on a half hour or so before you get home from work and a half hour or so after you typically go to bed. This will give the box plenty of time to update the programming guide and finish warming up.

In regard to DVRs, we’d recommend not putting them on any sort of timer device. We have no way of knowing how the device is programming, what kind of disks are inside, and what kind of spin-down protocols and what not the manufacturer has set up. They designed the device to run 24/7 and cutting the power on what amounts to a simple computer with a mechanical hard drive is a great way to shorten the life of the device and prematurely do in the HDD (taking all your recorded content with it).

So in summary: experiment with putting your boxes on switches and/or timers (either you’ll have a box and cable company where this works or you’ll have a box/company combo where such an arrangement leads to agonizingly long boot/update times) and, high power consumption or not, leave your DVR alone to keep the drives happily humming along.

Have a pressing tech question? Shoot us an email at and we’ll do our best to answer it.

Image by Steve Johnson.

Profile Photo for Jason Fitzpatrick Jason Fitzpatrick
Jason Fitzpatrick is the Senior Smart Home Editor at How-To Geek. He has over a decade of experience in publishing and has authored thousands of articles at How-To Geek, Review Geek, LifeSavvy, and Lifehacker. Jason served as Lifehacker's Weekend Editor before he joined How-To Geek.
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