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View Full Version : is it rue Plasmas use more power than lcds?



greensnib
16-08-2006, 05:39 PM
A mate was saying that Plasma TV's use up more power than LCD's and are more expensive to run. anyone know about this?

sammo
17-08-2006, 12:41 PM
Both LCDs and Plasma screens use about four times more electricity than a CRT.

In Plasma's the extra energy is needed to excite so many individual pixels, with LCDs the energy is required to power the backlight, which is usually mercury based.

The-Wappy-One
17-08-2006, 12:58 PM
Both LCDs and Plasma screens use about four times more electricity than a CRT.
In Plasma's the extra energy is needed to excite so many individual pixels, with LCDs the energy is required to power the backlight, which is usually mercury based.


(:| (:| sorry m8 not true

The power required to run an LCD is about one-third of that required for a CRT with the same screen area. In addition, the amount of heat generated by an LCD monitor is considerably less than a CRT monitor, resulting in a lower load on air conditioning. Building cooling needs may be decreased by up to 20%.

So on a power scale for say a 32" TV Would be, (General rule of thumb)

1st. LCD
2nd. CRT
3rd. PLASMA

the avrage's are

LCD: 0.16 to 0.41 watt per square inch
CRT: 0.25 to 0.40 watt per square inch
Plasma: 0.30 to 0.39 watt per square inch

see here

20 TVs' power consumption compared - TV power consumption - CNET reviews (http://reviews.cnet.com/4520-6475_7-6400401-3.html?tag=nav)

and look at the Per square inch side as all the tvs are diffrent sizes so the Per square inch will give you a good guide

Wappy

also remember poorly or cheap tv may consume more power.

Yo will allways find one lcd that uses more that the best tv but this is done as a guide


But while Plasmas use more they stay small for there size... eg i'd hate to see the weight of a 42" CRT (:| (:|

sammo
18-08-2006, 02:55 PM
Hmmmm....I'm not convinced you're right m8 sorry.

I'm not so sure a direct comparison can be made using the methodology the cnet review adopts i.e. I'd question the usefulness of power consumed by sq inch as a meaningful unit of measurement, especially when derived from manufacturer's specifications. You can't trust everything you read on the internet m8.

A much more telling variable when assessing power consumption would surely be time operating, as for a start, doesn't the amount of power an LCD TV use depend on the type of picture it is displaying (the brightness etc...)?

But I can't find any really good stats after a quick google search and I'm far from an expert with this:) . The information I have is from the UK government sponsored Energy Saving Trust, Energy Saving Trust - energy efficiency & conservation - EST.org.uk (To view links or images in this forum your post count must be 1 or greater. You currently have 0 posts. who recently published a report called "rise of the machines". They use information from something called the market transformation programme, a government advisory body.

Take a look at this on their site and let me know what you think:
Market Transformation Programme - Supporting UK Government policy on sustainable products (To view links or images in this forum your post count must be 1 or greater. You currently have 0 posts. the majority of LCD displays, this backlighting is provided by high-intensity fluorescent or discharge lamps which can provide the light intensity, uniformity of diffusion and colour-rendition required for viewing of TV pictures. Whilst the LCD matrix and its driver circuitry use low amounts of energy, these lamps can consume significant amounts of energy. In larger LCD (primary) screens energy consumption is typically 380W."


and this if you can be bothered:
To view links or images in this forum your post count must be 1 or greater. You currently have 0 posts. I don't think they'd be proposing a standard performance of 325W by 2010 for LCD TVs if the power consumption was as low as you are suggesting.

The-Wappy-One
22-08-2006, 12:18 PM
hmm just had a Quick looky and i mean QUICK look at the links and will read them a little more later.

But it states "proposing a standard performance of 325W by 2010 for LCD TVs" if im reading right

But yet

Arianet HD Compatible 32" Widescreen LCD TV
From Aria.co.uk

379.95 exc vat (it's Only a Cheap'o)

Power consumption: Operating: 190W, standby: 4W

That allready bet's the standard for 2010 (:| and there is nothing special about that unit other than its cheap so it probably made of cheap components .

Sorry if i've miss read anything there and put a pants answer down lol



Edit ----

Just found this that If taken on board will lowsr power even more

Vikuiti%u2122 Dual Brightness Enhancement


Chemical giant 3M says it can save the world 33 million barrels of oil, if LCD TV manufacturers adopt a new film it has created.


he company's Vikuiti Dual Brightness Enhancement Film D400, or DBEF D400, can cut power consumption in liquid-crystal display TVs by 20 to 30 percent without dropping brightness or picture quality, said Dave Iverson, business manager for LCD TVs at 3M, who spoke at the Society for Information Display conference in San Francisco, California.


Those watts add up. Over the next five years, an estimated 315 million LCD TVs measuring 21 inches and above will leave factories, Iverson said. Assuming DBEF D400 will save an average of 25 watts on each TV, the material will save 57.5 billion kilowatt hours worldwide over five years, if these TVs are watched on average for four hours a day (315 million TVs by 182.5 kilowatt hours per TV over five years).

That translates to 33 million barrels of oil or 23 million tons of coal.

sammo
07-12-2006, 05:01 PM
BBC NEWS | Magazine | Do flat-screen TVs eat more energy? (http://news.bbc.co.uk/1/hi/magazine/6188940.stm)

for anyone still interested

mikey
08-12-2006, 12:33 AM
"Power consumption: Operating: 190W, standby: 4W"

Interesting the standby power is only 4W. The media always seem to claim the same power used in standby as in use.

Bainsy
08-12-2006, 02:42 AM
BBC NEWS | Magazine | Do flat-screen TVs eat more energy? (http://news.bbc.co.uk/1/hi/magazine/6188940.stm)
for anyone still interesteddosnt that link just say plasma eat more fuel cant see anything about LCD but only had a quick look so i could have missed it

little_pob
08-12-2006, 09:40 AM
From sammo's link:

Peter Raynes, professor of opto-electronic engineering at the University of Oxford, says modern LCD screens use a similar amount of power to bulky old cathode ray tube (CRT) televisions.

@Mikey that is for that LCD in standby. CRTs use about 60% of their operating power when in standby mode, as all they do is turn off the tube. LCDs turn of the backlight and the LCD matrix, the 4W will be to power the standby light, IR receiver and trickle power through the invertors for the backlight for a quicker start-up. Either way, standby is money and power down the drain, and I agree with the government's wish to ban the option from TV sets in the non-to-distant-future.

Interestingly the Plasma manufactures who've made the plasma-lcd-facts.eu website claim that the running costs of Plasma vs LCD actually averages out: Energy use (To view links or images in this forum your post count must be 1 or greater. You currently have 0 posts. it is not mentioned whether this claim is based on screens of the same size or watts per square inch)