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."

Black background?

[John Betonschaar]

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?

Only applicable for CRTs

[advocate_one]

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.

silly

[Gabest]

lcds have a backlight, it only covers the light for black, it won't save any energy.

This is pretty much nonsense

[grahamtriggs]

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.

No savings on LCD:s

[Depili]

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...

Are we sure this helps?

[ddt]

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.

How the hell would this work?

[Sycraft-fu]

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.

OLED

[aembleton]

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.

Re:Oh, the irony....

[Don_dumb]

I think that is hypocritical as opposed to ironic.
But it is a good point, that site decided to use a white background, why? Is there some simple asthetic reason why a site would choose white or lighter colours over dark?
Or is it even simpler than that and no one has actually stopped to think about that.

Save energy by switching off your monitor

[rossdee]

and don't use a fancy scrensaver, just a blank screen.

It's all about priorities

[ben there...]

Somehow I suspect 116,144.654 is a bit overblown, and the About section amused me because obviously setting Blackle to your homepage only saves energy if you have Google for your homepage in the first place.

Yeah, but setting blackle.com as your homepage earns blackle.com a whole lot of money from Google Custom Search.

How can you help?

We encourage you to set Blackle as your home page. This way every time you load your Internet browser you will save a little bit of energy. Remember every bit counts! You will also be reminded about the need to save energy each time you see the Blackle page load.

Help us spread the word about Blackle by telling your friends and family to set it as their home page. If you have a blog then give us a mention. Or put the following text in your email signature: "Blackle.com - Saving energy one search at a time".

Think about how much energy we would have saved if we all didn't read this spamvertising.

Re:This is pretty much nonsense

[1u3hr]

The vast majority of people run LCD monitors these days.

No they don't. The majority of monitors sold surely, but monitors last for many years. Mine is over 10 years old, and has survived three or four PCs. There are a lot of old systems and even older monitors in use.

A pittance

[DrHyde]

Even if it did save 750MWh a year, so what? If you assume that on average a home uses 1kW an hour (which when you consider all of the slashdolt readers' computers being left on all the time seems like an underestimate) then that's 8.7MWh a year, or just over 1% of that 750MWh, so you're saving at most the energy output of just 100 homes. That miniscule saving comes at the expense of making the pages *much* harder to read. If you want to save energy, then how about making US cars to the same efficiency standards as European cars.

Re:Oh, the irony....

[Professor_UNIX]

Black background with bright letters is NOT easier on the eyes.

You're one of those freaks who used to like the xterms with yellow backgrounds and black foreground huh? The first thing I do when I get a new terminal is change all the backgrounds to black and the foreground to light grey or white... it IS easier on my eyes than a dark color on light backgrounds.

Re:Only applicable for CRTs

[Anonymous Coward]

Suppose the numbers are right and a black background could save 750 megawatthours per year. That's an average of 85kW. They want Google to use an unergonomic and marketingwise disastrous background color to save 85kW of electric power? The solar array on the roofs of the Google campus has a capacity of 1.6MW.

Re:WHY IT GOTTA BE BLACK!??!!

[hwojtek]

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?

Re:Oh, the irony....

[looseSpark]

Am I the only one who likes a light green text on a black background? I do actually find it much easier on the eye (and easier to read) than a white or light grey text.

Also, although I never used the old green screens much, it does give it a nice retro feel.

Re:This is pretty much nonsense

[vtcodger]

***The vast majority of people run LCD monitors these days.***

The vast majority of your friends may run LCD monitors, but it's unlikely that LCD monitors have replaced even half the CRTs in the general user population. Techies are prone to overestimate the rate of adoption of new technology.

For that matter, they are still selling CRTs -- and they are cheaper to buy if not to operate -- than LCDs. Check the ads in your Sunday paper and look at what sort of monitor is on the low-end, loss-leader, offering.

Perfectly usable used CRT monitors are only a few bucks. I'm going to put one out front in the next few days with a FREE sticker on it and see if it goes away.

Re: LCDs consume more power to create black

[DataSpring]

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.

Re:silly

[FlopEJoe]

So we should use black backgrounds in the summer to save on AC but use white in the winter and gain a little extra heat. I suppose it would take awhile to add up to real savings but, as they say, "if everybody did it..."

Re:Oh, the irony....

[Anonymous Coward]

Yes, you don't blind your readers. Black on white is much easier to the eye.

You might actually want to re-think that. White on Black is far softer on the eyes. Go check out the accessibility option and ask yourself, why is "high contrast" mode set so that you have white text on a black background. Honestly, I wouldn't be surprised if a big reason my eyes are tired after staring at a display all day doesn't have something to do with the fact that a large amount of the text is black-on-white. There is a reason I prefer my terminal windows in black-on-white. The only problem with black background is you might have to be more careful with your color selections for text, though this can be a problem with white backgrounds as well. (I cannot think of why anyone would put yellow-on-white though.)

Re:Some real figures

[jack_csk]

Given that the fluorescent light on the LCD is illuminating even on black background webpage, that doesn't suprise me.

Since the energy saving figure is based on CRT monitors (as the Wall Street Journal blog pointed out), the most significant improvements would be switching to LCD whenever you have to replace a wear-out CRT.

Re: LCDs consume more power to create black

[camperdave]

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.

Re:Some real figures

[Moniker42]

It's not surprising really... On a CRT, i don't really know - but i assume that most of the power would be taken up by the heater and not by the electron gun that lights up the screen. On an LCD however the most amount of charge is applied to a black cell, because the way an LCD works (in simple terms) is by compacting the liquid crystals (by delivering a charge) to prevent light escaping, and to produce the colour white the liquid crystals are relaxed, less charge is dropped across the cells of liquid crystal. Again, most of the energy will be consumed by the back light of the LCD (much like a fluorescent office light i believe) so the energy difference is negligible.

Re: LCDs consume MORE power to create black

[arete]

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.