[jlupine]

We keep hearing that televisions, especially large, flat-panel models, are always "on" and thus always using electricity.  I was wondering why they are always "on", and therefore what the effect would be of turning them "off" when they're not in use.  Three obvious possibilities are:

1) Sets last longer because they're not undergoing inrush current surges, on-off and electrolytic-capacitor charge-discharge cycles, etc.
2) Sets are viewable sooner because they're already warmed up.
3) Sets reach peak performance (sharpness, color intensity and balance, e.g.) sooner for the same reason.

What are the most important reasons ?  I'm certainly willing to wait a few minutes for the set to warm up, but I don't want to reduce my electrical bill by sacrificing the television's longevity.

Jan   

[Bob in St. Louis]

Repeated voltage spikes from "yanking the plug" can't be good.....I wouldn't think.
Also, some sets may have volatile memory meaning that certain settings will be lost if it's disconnected for an extended period of time. Like calibration maybe?

Have you checked the idle amperage of your set? It's probably not much. In the grand scheme, there' quite a few things that are still 'on', even though they're off.
Microwave ovens, computers, etc...

Bob

[Kevin Haskins]

They are "always on" because they have a small microcontroller that is there for the remote control & logic.    The buttons on the front function via that microcontroller so it has to be powered in order to respond to the button & remote.

The power consumption is typically < 0.5W so it isn't a lot of power.   

[BradJudy]

What Kevin said.

Until recently, the Energy Star rating for TV's just meant that the power consumption at standby was <1W (if I recall correctly).  Late last year, they added maximum full-power ratings for TVs with Energy Star rating.  This page describes the formula for the new standard - http://www.energystar.gov/index.cfm?c=tv_vcr.pr_crit_tv_vcr

For example, a 40" diagonal 16:9 HDTV is ~684 sq in in area, which means it could consume a maximum of 191W at full power to get an Energy Star rating. 

I put a Kill-a-watt on my TV to measure the power-on consumption and it was much lower than the manufacturer listed spec, which was nice (I think they have to spec at max consumption, with features enabled and brightness cranked). 

[BradJudy]

FYI: I just played with the Kill-a-watt on my TV and found that at my standard settings, it uses 125W while watching.  I tried playing with a couple settings and most didn't do much, but the display mode had a major impact.  Switching from "standard" mode to "dynamic" increased the power consumption to 225W (in addition to other things, it appears to boost the backlight output). 

[Bob in St. Louis]

Hey Brad,
What is your TV using when it's turned off? (but still plugged in)
Have you tried other things in the house that are turned off?

Bob

[BradJudy]

The Kill-a-watt doesn't measure below one watt, so the TV fluctuates between 0 and 1.  I haven't tried it much on other devices in standby.  I've been meaning to test my Dish DVR because I think that one pulls a lot of juice all of the time.

[Kevin Haskins]

You also have to consider that not all that power is wasted.   If your heating your house anyway, the power loss is given off as heat.   We live in a very temperate climate where it is cool year round and we heat with electricity.    In the winter if my TV gave off 200W or 500W it wouldn't matter because I'm heating that space anyway.    If you live in Florida and you run your AC, it is another story.

The big plasmas eat the most power and the newer LCDs are more efficient.     If you want to be econo-friendly buy a small LCD and use it infrequently.    Use Class D amplifiers to power speakers and design the system with efficiency in mind.    You can design your entire equipment rack to have a hard/switch to cut all power to all the components.    You have to be careful with things that store stuff in memory but for a simple TV/Stereo it shouldn't be an issue.    Those cable box things are HORRIBLY inefficient.    Just drop cable and that solves that problem and you won't have to suffer through all the crap on TV.

[Bob in St. Louis]

If it's below one watt, I'm thinking it's insignificant anyway.
Unless you're running your entire house on windmill/solar power and counting every electron, that's a "waste" I'm willing to live with.
Of course I've been running a 40wpc tube amp and a couple solid state toroidals for about 16 hours a day recently, so I can't complain much anyway. 

Although, I'm still curious to Jan's original question of whether or not it's wise to yank the plug on a modern display devise.

Bob

[mjosef]

I think the modern flat panel sets would lose their settings after a certain amount of time unplugged. Not 100% certain about that though. My Phillips dvd player defaults to factory settings after being unplugged for more than 5 minutes.

[BradJudy]

I can't speak for others, but my Samsung LCD does not lose settings when unplugged for extended periods.  When going on vacation, I usually turn off the power strip that it is plugged into and it has always retained the settings.  It doesn't take much for a company put a bit of non-volatile memory into a device for storing settings and consumers are quick to complain if settings are lost. 

[Bob in St. Louis]

My old DirecTv receiver use to take ten or fifteen minutes to find it's brains after the power was removed, even only for a second. Was a real PITA while trying to watch the weather report during a bad storm when the power blinks off and the satellite receiver has to "reload" (or what ever it was doing).
We've since switched to Dish Network (not due to this reason though), but the power hasn't gone off since we've had this receiver so I don't know what it'll do if the power goes off.

Bob

[BradJudy]

I just tried it on my Dish HD DVR.  It pulls 40-50W when idle and 50-55W while active.  The active power consumption stayed the same if I was watching live TV, recording, or recording one channel and watching another. 

[Bob in St. Louis]

40-50W when idle! 

Jeez man..... 
No wonder those suckers get so warm.
So much for "being green"..... Wait til the eco-greenies get a hold of the Sat companies.

Bob

[Kevin Haskins]

40-50W when idle! 

Jeez man..... 
No wonder those suckers get so warm.
So much for "being green"..... Wait til the eco-greenies get a hold of the Sat companies.

Bob

It is the same for the cable box thingies.   I didn't have to run my furnace when that thing was plugged in.   

[BradJudy]

I think most DVRs never really turn off, they just switch off the outputs.  I'm surprised that there isn't more of a difference between the two states.  I figured the video processing would burn more CPU cycles and eat more power.  I imagine the non-DVR boxes consume far less power and have pretty low-power idle states.  

Another interesting note - when I first plugged it in, the fan kicked into high during the initial boot-up, and it only dropped about one watt in power consumption when the fan kicked down.  I don't know about airflow, but that fan sure produces a lot of noise for one watt. 

[jlupine]

Thanks, everyone.  My television is a 50" plasma, not Energy Star certified.
I wrote to the manufacturer, and the response was that it uses 0.2 watt when turned off.

[jqp]

I just tried it on my Dish HD DVR.  It pulls 40-50W when idle and 50-55W while active.  The active power consumption stayed the same if I was watching live TV, recording, or recording one channel and watching another.

wow that is a lot of juice all day long - I guess it has to be always ready to record show 1 at 8pm and show 2 also at 8pm...I guess the thing is constantly decoding the satellite on one or two channels, and doing decryption, always ready to record and switch channels