Slashdot Mirror
Power-Saving Web Pages: Real Or Myth?
An anonymous reader writes "Are dark webdesigns an energy saving alternative to a snow white Google? The theory is websites with black backgrounds save energy, based on the assumption that a monitor requires more power to display a white screen than black. Is this a blatant green washing ploy by Blackle.com, or an earnest energy saving tweak for a search tool we use every day? To find out, PCSTATS hooked up an Extech Power Analyzer to a 19" CRT and a 19" LCD and measured power draw — turns out there is a not insignificant difference ..."
I bet "Anonymous Reader", our submitter, who probably shills for "blackle.com", "believes" it.
I can't decide if this story is an intentional slashvertisement or an astroturf.
"Blackle.com"? Really? It's only slightly clever to raise the possibility that they're trying to greenwash the issue of "website-specific power consumption", especially since TFS very conveniently refutes that. ("not insignficant?" Sheesh.)
Welcome to the Panopticon. Used to be a prison, now it's your home.
Maybe PCstats should apply their own power-saving strategies to themselves (less CPU-intensive flash crap).
Anyway it appears only the CRT has a significant savings with White google versus Black blackle.com. LCDs gain almost nothing.
My AC stalker: " I personally agree with your posts most of the time, but that won't keep me from modding you troll"
Firstly, I'm extremely skeptical of one of the conclusions - 'flash will make a CRT monitor use more power' - which I just don't believe - it will use an amount of power dependent on the average screen brightness - which may be an increase over black.
LCDs are different - the panel does actually take some energy to change state, and the lag compensation circuitry will use more in motion.
Secondly - a huge part has been missed out of this.
Power consumption of the computer.
Flash, or javascript, even in the background, can considerably increase power.
For example, I just closed all of the flash/animated things in the background on other tabs in firefox, and the CPU usage is now bouncing around 2%, with the computer using 17W.
If I start up a new tab with some flash, and gif animations, it goes up to 25W. (+8W)
Even switching away from the tab only takes it to 23W or so. (+5W)
It would be interesting to work out the total electricity wasted by common flash ads.
It would have been interesting to include the whole computer in the power measurement. How much more electricity is drawn by a javascript infested site than one that is just static HTML and images ? How much more is drawn if there are 100 components to build the page instead of 20 (don't forget to include the consumption of your broadband modem, etc, ...) ? How much more electricity does flash use ? How much more through heavy use of AJAX ?
The biggest difference that they showed was that the use of a glass monitor was about double that of a LCD. With an LCD the CPU/... consumption would be a bigger fraction of the whole thing.
You should hate it. It's a shitty hack to make it look like your LCD has better contrast on paper.
I briefly owned a display like that. If I turned the dynamic contrast off, it looked washed out, and no amount of tweaking would get it looking even halfway decent. It was a shitty LCD but it was also 1/3rd the cost of my current photorealistic dazzlers.
It's the visual equivalent of the bass and treble boost knobs on cheap stereos.
-Billco, Fnarg.com
People still have CRTs?
How ridiculous.
Ability to display perfect black color;
Ability to display more than one resolution correctly (useful for games, old video card = new games at reduced resolution);
Ultrafast response time, no input lag;
Reliable and have long life (people saying things like "My LCD started acting weird, but it's 3 years old, time for a new one", while my 12 year old CRT works great), but can also be repaired if necessary (well, other than the failure of the tube obviously);
More affordable than a 24" LCD that can display 2304x1440 (if such a thing even exists);
Great image quality.
The only advantages of LCDs are size, weight and power consumption - all of these are not primary features of a monitor, at least for me (the same way that I don't buy a car based solely on the fuel consumption, or a computer based on its power consumption and size - I look for performance and cost first).
I know way too much about printing, but I can't find anything about this "black creep" online, but it sounds exactly like dot gain. Well, except for you thinking it's in people's eyes.
Oh, so very, very much this.
Let me count the problems with light-text-on-dark-background:
1) If you have cataracts, corneal irritation, or smudged glasses, bright objects against a dark background are MUCH harder to resolve than dark images against a white background. With black-on-white, you just get reduced contrast; with white-on-black, you get distracting smears and rays all over the page.
2) In a dim room, your pupils dilate more if the scene before you is mostly dark, and dilated pupils generally produce poorer acuity. A bright background causes your pupils to contract, and just like stopping down a cheap camera lens, it improves the focus of the image hitting your retina.
3) In a bright room, a mostly-dark display will be more obscured by reflections and glare.
This is one reason I stopped hanging out at dpreview.com. Yeah, I know, photographers think their stuff looks better against a black background, but more than five or ten minutes on the site gives me a headache.