Wednesday, July 22, 2015

Who killed the vampire loads loads in my entertainment system?

In a recent post I wrote about replacing my dead 37" LCD TV with a new 50 inch unit.  I didn't realize I was buying into an entirely new AV ecosystem.  I got talked into purchasing a sound bar for the TV which completely replaced my old-style stereo amplifier that I originally used for the sound system for my TV.  So I have completely restructured my entertainment system and in the process I have taken detailed measurements of its power consumption using a Kill-A-Watt meter.  The biggest take away I have gotten from this experience is that over the last 10 to 20 years new appliances have dramatically reduced their phantom loads.  A phantom (or vampire) load is the power an appliance consumes when you think it is "off".  In an entertainment system this includes all of the devices that you can turn on remotely.  They have an internal circuit that sits there all day waiting for a signal from your remote control and that consumes a certain amount of power - sometimes several Watts.

My original entertainment system consumed around 9 W in standby mode not counting the DVR and I used a timer to turn everything off from midnight to 6 PM thus reducing the load to the timer itself which is only 1 W:
My new entertainment system is significantly more efficient, not only when everything is on, but also when all of the devices are turned off.  My Kill-A-Watt could not get a valid reading for the TV, sound bar or Fire TV (streaming video) box because it is below its measurement threshold of 1 W.
I have recycled the DVD player, stereo amp, and CD player because I no longer need them.  The new sound bar lets me play my music via Bluetooth from my tablet or from the cloud using the Fire TV, and who uses CDs anymore these days?  So now my power consumption when watching TV has dropped from 223 W to around 102 W.  A 50% reduction.  Here in Maine we pay approximately $.14 per kilowatt hour, and if we assume I watch TV for five hours a night which is considered average then the monthly cost drops from about $4.68 to $2.14.  So I am saving over $2.50 on my electric bill every month.  (Actually I don't pay for electricity during the summer months because my solar array generates a surplus!).  If you extrapolate this across all the entertainment systems worldwide, this energy savings is really significant.

By the way, in the process of setting up and configuring the new TV, I learned that by adjusting the brightness setting I could reduce its power consumption from around 73 W down to around 50 W without any significant compromise in image quality.  You may want to dig into the settings on your TV and see how low a brightness setting you find acceptable.  If you do this while the TV is plugged into an energy meter, you can balance brightness versus power consumption.  It may take a period of adjustment to get used to a slightly less bright TV, but the default settings are usually much brighter than is necessary.

I think the drop in power consumption has a lot to do with advancing technology, but also some push back from consumers who want more efficient appliances.  Over the last several decades televisions have dramatically improved their operating efficiency as they transitioned from old-style CRT tubes to cold cathode backlit LCD screens to LED backlit LCD screens.  Similarly, engineers have found a way to reduce those pesky vampire loads in the entertainment systems.

So if you are overcome by "consumer-itis" and decide you need to upgrade your entertainment system, you may find that your electric bill drops significantly while your viewing experience is enhanced.  Guilt free TV! - who knew?  Just don't forget to recycle your old equipment.


  1. I think the main culprit in vampire loads was their power supplies which had to be larger and, at the same time, were less efficient. Second the designers use better low power standby capable processors. Both improvements are largely thanks to companies like Apple and Samsung needing those features for their smartphones so they might last all day while still being reading to power up instantly. Now we need to get the cable and satellite DVRs into the 21st century power wise.

  2. Wow! We just bought our first LCD TV recently, before that we just streamed on the PC. I wondered about how much that little red "ready" light on the TV was costing us--nice to know you've actually measured it and the results were reassuring. Thanks.


I welcome all thoughtful comments and feedback!

Note: Only a member of this blog may post a comment.