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Change Google's Background Color To Save Energy?
i_like_spam writes "Recent commentary at Nature Climate Change describes an on-going debate about the energy savings associated with the background colors used by high-traffic websites such as Google and the NYTimes. A back of the envelope calculation has suggested energy savings of 750 Megawatt hours per year if Google switched their background from white to black. In response, a new version of Google called Blackle was created. However, other calculations by the Wall Street Journal suggest minimal energy savings."
A site that criticizes google for having a light background itself uses a light background.
File under 'M' for 'Manic ranting'
A back of the envelope calculation has suggested energy savings of 750 Megawatt hours per year if Google switched their background from white to black. In response, a new version of Google called Blackle was created.
Once Google has gone Black, they'll never go back. That's what I hear, anyway.
The theory of relativity doesn't work right in Arkansas.
I wonder how much of the 'energy saved' will be consumed by all those machines they use in the hospital for people who get eye problems from staring at white/grey on black text.
Also, You'd think changing your desktop background to solid black would make more of a difference then just changing google. I spent at most 10 minutes a day with the Google page open. And it's not that there's no other site that uses a white background. How much energy do flashing ads consume btw?
TFT backlights are still on even if entire page is white text on black... they only go off when energy savings kick in and turn the display off.
Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
lcds have a backlight, it only covers the light for black, it won't save any energy.
PLEASE USE BOLD AND UPPERCASE IN YOUR COMMENTS. A +5 COMMENT IN BOLD AND UPPERCASE SAVES 5 DONKEY-FORTHNIGHTS OF THE ENERGY
The vast majority of people run LCD monitors these days. For the most part they run with a backlight of constant brightness - so there is no energy saving with a black screen.
Only if the LCD detects a dark screen, and adaptively lowers the backlight, will there be any energy saving.
As TFT displays seem to be more common than CRT:s nowadays, the energy savings are minimal to non-existent, as the TFT backlight won't get turned off...
Most computers these days use LCD screens, and most LCD's use flourescent tubes as a backlight, which is what creates whiteness. If you put your ear really close to your screen, it's also what creates a faint hum. Those tubes draw most of the power on a display, and they don't turn off just because the screen goes black.
I don't think changing the colour to white changes the power draw significantly. It just means more of the flourescent tube light is passing through the screen.
All LCD screens get their light from a single backlight. When the display is on, the backlight is on. Always.
The LCD crystals in the screen act as tiny shutters, and can open or close to allow that light through, or keep it out. Although these shutters take a small amount of energy to open and close, it's insignificant compared to the amount of energy it takes to power the backlight.
A commenter in this thread commented that an Apple 17" display attached to a lab supply is measured as drawing 0.6W less when displaying a white screen than when displaying a black one.
CRT screens probably do draw less power when displaying a black screen, but on the whole they still draw considerably more power than an LCD under any circumstance. On the same note, CRT users may find that the white-on-black scheme is easier on their eyes -- I still have a CRT in my cube at work, and setting my editor to the white-on-black scheme is definitely more legible and less stressful on my eyes. (I still find it more legible on LCDs, although eye strain isn't an issue at all)
I don't get it... CowboyNeal should know better than this. Is he intentionally seeding flamebait?
-- If you try to fail and succeed, which have you done? - Uli's moose
It's not like it takes any less power to transfer the bits or anything like that, so they must be talking displays. Ok, fine, maybe (and I do emphasize maybe) this would work if we were all on CRTs but we aren't. LCDs are dominant these days. Well, their backlights are always on. They work by blocking light, not by emitting it. So their power consumption is constant, regardless of what the panel is doing.
To me this jsut sounds like more BS "Get more from less!" crap from people who probably aren't willing to make the simple changes that will actually, really make a difference.
Look, if you want to use less energy have your computer turn off monitor, disks, and suspend sooner, replace incandescent bulbs with CFLs (there are good full spectrum ones out there that give nice light), get a programmable thermostat and add some weatherstripping around doors and windows. It's simple, cheap and will do way more than crap like this.
Most new monitors are LCDS. LCD's are generally backlit and black is achieved by having all the pixels opaque. So wouldn't black cause a higher power usage? or just break even?
"There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy."
It will provide at least 50% in power savings.
Then again, that extra money might get taken up in seizure meds.
I guess this could work with future OLED displays that only emit light on each pixel if it is needed, so a black background would require minimal energy. However, my current Samsung TFT monitor draws 40W whether it is on or off which I believe is due to the power transformer that it uses. Even with alternative displays, energy saving might not occur due to these power transformers.
and don't use a fancy scrensaver, just a blank screen.
TN+Film ones, by far the most common, do. They have to be energised to go black, their no power state is open which is why the pixels fail to white. VA (P-MVA, S-PVA and so on) and IPS (S-IPS and such) don't because their no power state is black and have to be energised to open and thus fail to black.
Regardless the energy used on the panels isn't much in comparison to the backlight. That's why companies toy with reflective displays (like the old Game Boy Advances). It does really well for battery life when there's not a backlight. That's what sucks the energy.
Yeah, but setting blackle.com as your homepage earns blackle.com a whole lot of money from Google Custom Search.
Think about how much energy we would have saved if we all didn't read this spamvertising.
In a decade or two it will probably all be e-ink based so there will be no difference. Except it would need to be illuminated in the dark.
Unless they make a hybrid with oled in the dark and e-ink in the light. Then a light background would waste electricity at night and strain your eyes more.
So have a dark background at night and a light background during the day like reading paper, that's it, web pages that adjust their display depending upon your surroundings.
Maybe I should have kept that to myself...
POWER saving of the darkside...
Skywalker: pardon?!
I belive black would turn down the power usage on a CRT, but LCD running white (no voltage applied to the cells, so no dimming) uses less energy... Or am I wrong?
Wojtek
Exactly what I was thinking! (The way LCD's produce black is to energize all the pixels that need to be black, "illuminating" them, which makes them opaque, and "get in the way" of the backlight, which is always on.) So, this would effectively *increase* the power consumption of LCD monitors, which are more prevalent everyday, and probably the majority of monitor sales these days.
I've just tested this on a Sony 15" LCD monitor (M51?).
Google.com: 18.5 watts
Blackle.com: 19.5 watts
Slashdot: 19 watts
so it would seem that using blackle is using about 5% more power.
So the black background might make your monitor warm up, but it won't use any additional energy.
Of course it will. It takes power to twist the liquid crystals to make black, power that is not applied to make white. The backlighting isn't the issue. Even the original poster mentioned that the backlight is on constantly.
When our name is on the back of your car, we're behind you all the way!
Who needs Blackle when there's userContent.css? Google's been white-on-black on my machines for years. Same with /. It's just easier on the eyes.
.t { .p, a { .w, a.w:link, q:visited, q.link, q:active, .q {g );
@-moz-document url-prefix(http://google.com), url-prefix(http://www.google.com) {
body,
background: black !important;
}
body {
color: white !important;
}
body, td, div,
font-family: fixed-width !important;
}
a:link,
color: #3366cc !important;
}
a:visited,
span.a,
span.a:link {
color: #888 !important;
}
div, td {
color: white !important;
}
table.histTable td {
color: black !important;
}
div#navbar div,
table,
td,
div
{
background: black !important;
}
input[title=Search] {
background: black !important;
border: 1px solid #888 !important;
padding: 0 3px !important;
}
input[title='Google Search'] {
background: black !important;
border: 1px solid #888 !important;
padding: 0 3px !important;
margin-bottom: 20px !important;
}
img[src='/intl/en_ALL/images/logo.gif'] {
padding-top: 110px;
height: 0px !important;
overflow: hidden !important;
background: url(http://*************/google-black-276x110.jp
}
a#logo span {
background-image: url(http://*************/google-black-150x78.jpg) !important;
}
img[src='/images/google_sm.gif'] {
background-image: url(http://*************/google-black-150x78.jpg) !important;
padding-top: 78px;
height: 0px !important;
overflow: hidden !important;
}
div#gbarl {
display: none !important;
}
}
mod parent up, a lot.
The article references a DOE article from decades ago - and clearly before the predominance of LCDs - and another article full of comments about how the tests didn't bear this out on LCDs.
And if you REALLY want to save money on your CRTs, this is small potatoes compared to having a power strip for you monitor so you can cut all power to it at night - modern CRTs have a very substantial residual drain to keep the heater warm.
And you can set your machine to monitor-off earlier than sleeping - and since it wakes up from this fast, there aren't a lot of downsides. (This helps CRTs and LCDs...)
Finally, in many LCDs you can simply turn down the backlight - this is generally the largest power component in an LCD.
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You are right, as actually tested by a colleague using a power meter. With his normal, mostly white, desktop - 26W. Unplug the video so the monitor goes into "No Signal", which this particular monitor did not timeout - 28W. Not a great difference, but definitely going the opposite way to TFA.
Consciousness is an illusion caused by an excess of self consciousness.
I found that porn sites use mostly black backgrounds with light (usually pink) text. I've committed this research for over thirteen years, and I consider myself something of an expert on the subject...
Do not look into laser with remaining eye.