Power consumption - plasma vs. LCD vs. CRT TVs

dburna · « **on:** 5 May 2008, 10:28 pm »

A recent issue of "Real Simple" magazine listed some annual power consumption statistics for a variety of electronics equipment. The ones that interested me were the kW hours and annual cost estimates for each type of TV (plasma, LCD, CRT). The results are summarized below (for TVs smaller than 40"):

ITEM Annual Energy Use Annual Cost
Plasma TV 441 kWH $48.25
CRT TV 123 kWH $13.46
LCD TV 77 kWH $8.42

My question is: why do plasma TVs use more energy than a comparable size LCD? I'm assuming that plasmas are more power-hungry than CRTs because they are "partially on" all the time unless unplugged. But how does an LCD achieve higher efficiency ratings than either?

Any insight on this issue would be most appreciated,

-dB (a unit measure of noise)

P.S. I mention the source of the data because I can't confirm its accuracy or the assumptions that go into their estimates.

jonwb · « **Reply #1 on:** 5 May 2008, 11:17 pm »

Hmm... that is interesting... I have a little powermeter at home. If I get some time I'll do my own experiment. I have a 50" Panasonic plasma and a 38" RCA HDTV (no big LCD). Not that it matters to me a whole lot, I always figured the RCA uses a bit more electricity that the Panny. I'll check "standby" and "running" power for both. We'll see...

SET Man · « **Reply #2 on:** 5 May 2008, 11:38 pm »

Hey!

This is nothing new. I've heard this for sometime now.

The fact that Plasma use more electricity is because it need to heat up those cells filled with gas(es) to create plasma.

But for LCD you only need to switch on and off the liquid crystal on the screen.

I'm not an expert on this and that's all I know.

Anyway, it would be interesting to see the actual wattage listed on the back of a Plasma and LCD TV of the same side... give or take a few watts for audio use.

Take care,
Buddy

Bucky · « **Reply #3 on:** 5 May 2008, 11:57 pm »

The extra $35 for the Plasma is sure worth it though!

Folsom · « **Reply #4 on:** 6 May 2008, 01:33 am »

How much do projectors (nice ones) use?

My annual costs are zero because I do not watch stupid TV. Now I might rack up $2.00 worth of movies if I had something to watch with other than a laptop.

giantsteps · « **Reply #5 on:** 6 May 2008, 03:02 am »

Quote from: SET Man on 5 May 2008, 11:38 pm

Hey!

This is nothing new. I've heard this for sometime now.

The fact that Plasma use more electricity is because it need to heat up those cells filled with gas(es) to create plasma.

But for LCD you only need to switch on and off the liquid crystal on the screen.

I'm not an expert on this and that's all I know.

Anyway, it would be interesting to see the actual wattage listed on the back of a Plasma and LCD TV of the same side... give or take a few watts for audio use.

Take care,
Buddy

Hey Buddy..whazup? I just came back from Pennsylvania( wife's house) and all I know is that her 50'' Pioneer Kuro plasma(recommended by me) was an eyegasm for the time I spent there...don't give a f$#% what her electrical bill is.

Frank

Levi · « **Reply #6 on:** 6 May 2008, 04:00 am »

Plasma TV has lots of pixels. Each pixels (dots on screen) uses electricity. So according to consumer reports, 1020p uses more electricity than 720p plasma displays because of the number of pixels needed to lightup the screen. Also, You will notice that when the screen uses bright white lighting, electricity consumption goes up exponentially. On the other hand, LCD uses Backlighting. The higher the backlighting, the more electricity it uses.

Definitely Plasma cost of ownership is higher than LCD given that the LCD backlighting is not set very high.

Consumer reports data:

Quote

PRODUCT ANNUAL COST
20-cu.-ft. refrigerator (a newer top-freezer) $50
25-cu.-ft. refrigerator (a newer side-by-side) 65
32-inch picture-tube 40
36-inch picture-tube 50
37-inch LCD 50
40-inch LCD 55
56-inch rear-projection 65
42-inch plasma, 720p 70
52-inch LCD 80
50-inch plasma, 720p 80
50-inch plasma, 1080p 110

Folsom · « **Reply #7 on:** 6 May 2008, 05:55 am »

No projectors on the list! (just projection)

ctviggen · « **Reply #8 on:** 6 May 2008, 10:19 am »

Quote from: dburna on 5 May 2008, 10:28 pm

A recent issue of "Real Simple" magazine listed some annual power consumption statistics for a variety of electronics equipment. The ones that interested me were the kW hours and annual cost estimates for each type of TV (plasma, LCD, CRT). The results are summarized below (for TVs smaller than 40"):

ITEM Annual Energy Use Annual Cost
Plasma TV 441 kWH $48.25
CRT TV 123 kWH $13.46
LCD TV 77 kWH $8.42

My question is: why do plasma TVs use more energy than a comparable size LCD? I'm assuming that plasmas are more power-hungry than CRTs because they are "partially on" all the time unless unplugged. But how does an LCD achieve higher efficiency ratings than either?

Any insight on this issue would be most appreciated,

-dB (a unit measure of noise)

P.S. I mention the source of the data because I can't confirm its accuracy or the assumptions that go into their estimates.

That's only 11 cents/kwh. We're paying around 15 cents/kwh.

Personally, I don't think Consumer Reports knows their butt from a hole in the ground. Everything they say must be independently verified. For instance, if you have a 1080p screen and a 720p screen that are both the same size, who's to say that they don't use the same power, as each element of the 1080p screen is phyisically smaller and therefore lower in power? Did they measure this (probably not) or just make it up (probably so)?

samplesj · « **Reply #9 on:** 6 May 2008, 11:44 am »

Quote from: ctviggen on 6 May 2008, 10:19 am

That's only 11 cents/kwh. We're paying around 15 cents/kwh.

Its more of an average thing I bet. Even if the rate doesn't match a given person's the ratio will stay the same so the cost figures do have SOME value.

At the risk of really annoying the California and other high priced area posters, around here (thanks to lots of TVA dams) we only pay a bit over 8 cents/kwh.

Levi · « **Reply #10 on:** 6 May 2008, 01:45 pm »

Hey Bob,

Consumer reports can tweak the data just to make a point.

Not to mislead customers but to just make a point that higher resolution plasma displays use more energy.

-Levi

Bob in St. Louis · « **Reply #11 on:** 6 May 2008, 04:44 pm »

DOS - Regarding your projector (PJ) question; I've got a Sanyo PLV-Z2 (discontinued) that uses 210 watts.
Z2 specs: http://www.projectorcentral.com/Sanyo-PLV-Z2.htm

The new Sanyo PLV-Z5 also uses 210 watts. I'll let somebody else figure out what that works out to for a two hour movie.
Z5 specs: http://us.sanyo.com/business/projectors/home_theater/downloads/PLV-Z5_SPEC.pdf

Bob

giantsteps · « **Reply #12 on:** 6 May 2008, 05:23 pm »

BTW has anyone done the "pass your hand in front of the plasma screen test" at your local Best Buy or wherever? You will immediately notice that the Pioneer Kuros are the coolest to the touch. They consume almost half the electricity of the other plasmas. Truly an all around outstanding product.

Frank

dburna · « **Reply #13 on:** 7 May 2008, 01:48 pm »

OK, so LCD backlighting and more energy-efficient LCD pixels leads to lower cost, as this thread posits....higher numbers of pixels (and perhaps bigger screen sizes) lead to higher overall costs for flat-panel HDTVs.

Does this mean that one could unplug or cut the power on a plasma TV to save energy costs? Or does this result in reliability problems and/or frustratingly long start-up times? I saw a nice Panasonic plasma screen a week or so ago (Viera 42") that looked like a reasonable "acquisition target". I'd prefer not to use up the TV's useful life (and consume excess energy) by leaving it in some sort of semi-on state all the time, but I didn't know if cutting the power at the end of each listening session would have its own adverse operating impacts.

Thanks in advance if you know the answer to these questions.

-dB

Bob in St. Louis · « **Reply #14 on:** 7 May 2008, 02:06 pm »

I'd recommend that everybody get a projector. It's less money per square inch of viewing area.

Bob

giantsteps · « **Reply #15 on:** 7 May 2008, 08:48 pm »

Quote from: Bob in St. Louis on 7 May 2008, 02:06 pm

I'd recommend that everybody get a projector. It's less money per square inch of viewing area.

Bob

Couldn't agree more. My Panny 700 is getting old but with a new bulb she still has a WOW factor.

Frank

BradJudy · « **Reply #16 on:** 7 May 2008, 09:12 pm »

Here's something that lists power per square inch (still no front projectors) - http://reviews.cnet.com/4520-6475_7-6400401-3.html?tag=arw

Here's the short summary of averages:

Quote

* Microdisplay rear projector: 0.14 watt per square inch
* LCD: 0.29 watt per square inch
* Plasma: 0.35 watt per square inch

Once I found a better resource for this same info, but I can't find it now.

It sounds like modulated backlights for LCD TVs are getting going and reducing the power consumption while actually improving the image (dynamically dimming the backlight for darker areas).

dburna · « **Reply #17 on:** 7 May 2008, 09:17 pm »

So projectors are where its at, huh? I admit, I no even less about projectors than I do about conventional (LCD, plasma) flat-screen displays....which is to say, precious little. Where would I start to research these if I wanted to go in that direction?

Potential problems for my room: this would be deployed in a basement TV room that is thin (10' +/-), long (25-30') and with low ceilings (just under 7'). Mounting a projector at the back of the room doesn't seem feasible. Mounting it in the ceiling might prove difficult because of the low-ish clearance. Just not sure this would work in this configuration. Any ideas on this?

Thanks, -dB

giantsteps · « **Reply #18 on:** 7 May 2008, 09:24 pm »

Quote from: dburna on 7 May 2008, 09:17 pm

So projectors are where its at, huh? I admit, I no even less about projectors than I do about conventional (LCD, plasma) flat-screen displays....which is to say, precious little. Where would I start to research these if I wanted to go in that direction?

Potential problems for my room: this would be deployed in a basement TV room that is thin (10' +/-), long (25-30') and with low ceilings (just under 7'). Mounting a projector at the back of the room doesn't seem feasible. Mounting it in the ceiling might prove difficult because of the low-ish clearance. Just not sure this would work in this configuration. Any ideas on this?

Thanks, -dB

www.projectorcentral.com Everything you wanted to know about projectors and was afraid to ask.

Frank

Bob in St. Louis · « **Reply #19 on:** 7 May 2008, 10:03 pm »

Quote from: dburna on 7 May 2008, 09:17 pm

Where would I start to research these if I wanted to go in that direction?

My house, on your next visit to STL. We can talk about adoptions, audio, and video.

Quote

Potential problems for my room: this would be deployed in a basement TV room that is thin (10' +/-), long (25-30') and with low ceilings (just under 7'). Mounting a projector at the back of the room doesn't seem feasible. Mounting it in the ceiling might prove difficult because of the low-ish clearance. Just not sure this would work in this configuration. Any ideas on this?

Yup. It's possible.
One popular option for low ceilings would be to mount the projector (PJ) in a coffee table type situation. The cables can be 'snaked' under the carpet if need-be. Or....run the video feed straight back under one of the chairs with one of those "wires on the floor cover thingys" like you'd see in an office setting.

Quote

* Microdisplay rear projector: 0.14 watt per square inch
* LCD: 0.29 watt per square inch
* Plasma: 0.35 watt per square inch

The cost for my rig is about 0.0265 watts per square inch.

{210 watts. 5.5' X 10'} (the 5.5' is aprox)

Bob