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Energy Savings

I saw a posting today from someone recommending that black backgrounds on websites save energy over white backgrounds. Here’s the note:
“Hi folks, sorry for cross-posting, but I thought you would be interested to know about this, since we all spend so much time on Google. There is a black-background version of Google, which uses considerably less energy to display than the white-background version. I just ran some searches on it, and the text displays in grey against a black background, and is pretty easy on the eyes. It makes this email window seem like it’s glaringly bright, actually. Interesting idea! -Dawn
http://www.blackle.com/about/
http://www.blackle.com/ ”
I was sceptical. I’m no scientist (library scientist?) so I checked the usual sources. Well lo and behold it’s true! here’s teh DOE site:
Monitor Energy Information
Display Colors

White and bright colors (especially in backgrounds) can use up to 20% more power than black or dark colors. Look to the right to see the power usage (in Watts) of a sample monitor with different screen backgrounds. Unfortunately, e-mail and word processors tend to use white backgrounds, so your workstation uses considerable power while you are in these programs, which you are during much of the day. Because black-on-white is the most familiar (it’s just like the newspaper), selecting alternate combinations may not be appealing. However, you can change your desktop background to something efficient. You can change your background by selecting Start, Settings, Control Panel, Display, and Appearance tab. The “Item” field should say “Desktop”. Under color, select one of the colors at the right that has a rating below 65W and then click OK.”
20% saving isn’t inconsequential over millions of monitors! As a matter of fact, according the DOE site, white is the biggest user of energy.
The various hoax sites point out that the savings are lower for LCD vs CRT displays.
Also, there is updated info on screen savers:

Screen Savers

“Screen savers originally were not meant to provide energy reductions, but they now provide a means for energy savings. The use of dark screen savers can mitigate bright backgrounds, reducing monitor power up to 20%. Screen recovery occurs within 1 second by hitting a key or moving the mouse. Nearly all of the standard Microsoft screen savers are efficient. If you supply your own, please try to use one that uses primarily dark colors.” (more on the site)
Anyway, I was surprised. I try to be green (don’t drive, live in a co-op, recycle a lot, energy efficient appliances, etc.) so I’ll work on this too on our family’s plethora of PC’s.
Stephen

Posted on: July 25, 2007, 10:50 am Category: Uncategorized

10 Responses

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  1. Given that many (most) of us find white text on a black background difficult to read and a cause of eyestrain, it’s important to note:
    1. The big energy savings comes from switching from a CRT to an LCD.
    2. The informal study done of LCD power usage found any savings to be within the margin of study error. Not so much “lower” as quite possibly not there at all.
    That’s hardly surprising. Almost all of the energy used in an LCD is in the backlight, and the backlight should be using the same power no matter how much or how little of the light is getting through to the screen.
    So, for people using CRTs, this might be meaningful (or might not–after all, what percentage of computer use is actually spent searching Google?). For people using LCDs, I doubt that any measurable savings exist. Switching one 40watt incandescent to a 10watt CFL would almost certainly save much, much more energy.

  2. Mike Sonnentag said

    Hello,
    Great post/topic. Energy efficient devices/technologies are going to be crucial in driving down consumption. Lighting is such a big part of how the U.S. and world are using energy, so we need to keep improving those technologies. CFLs are a good answer for now, but OLEDs are another technology that may change the landscape in a few years. http://www.universaldisplay.com/white.htm
    GE and Konica mentioned they should have OLED white lighting in a few years. http://www.popsci.com/popsci/whatsnew/11723001344d3110vgnvcm1000004eecbccdrcrd.html
    I can be contacted at 610-642-8253 x 191 or at michael@gregoryfca.com.
    Thanks!
    Mike

  3. Remember when computer monitors showed white (or green) text on a black background? That’s how they all worked until the Mac was introduced. Apple did this because people read black text on a white background much better. It’s easier to do, and it’s easier on the eyes. It was a significant step forward in human-centered design.
    I for one am not willing to reduce my productivity and water my eyes for a small energy savings. Besides, if my productivity plummeted, I’d need to run the coffee machine more often. 🙂

  4. Susan said

    I truly hope this doesn’t lead to a trend of tiny gray type on black pages, as the “about” Blackle page made my eyes absolutely swim. It was almost unreadable. And no, I’m not that old. Perhaps with a larger type size it would work — the Google, er Blackle, results weren’t so bad. It’s an interesting concept, but the readability left a lot to be desired.

  5. On the topic of energy savings, we attached our computer and all peripherals to a surge suppressor which we turn off when not in use. We do the same with our TV & VCR. Then we made it a point of turning off the computer when we were not going to be using it for more than a few minutes. That cut about 30 kwh off our electricity consumption for the month.

  6. I find the other version Darkoogle.com is more easier to read since they uses green text just like the old days. Green text are more easy to our eyes and reduce eye strain

  7. Dave Netz said

    Yesterday I read ads in Newsweek and Popular Science for a device that will increase the average gas mileage on your car to 100 mpg. This is a pure scam and I wonder if these publications have any standards when it comes to advertizing. I hope that I will be proven wrong, and this device really works, but currently I think it is another bridge for sale.
    +++++++++++++++++++++++++
    I wouldn’t have paid attention. I’ve never bought gas or driven a car. I remain amazed at what people will pay for tap water in bottles! Way more than gas prices.
    SA

  8. I prefer http://www.keepglobe.com over Blackle. They donate 50% of revenue to a green cause and it is hosted on a server that is powered by wind and sun energy. They also have an image search. Black search engines do not save energy as they claim and also my eyes twitch after seeing that black background.

  9. A few months ago Google busted this myth (I think) on their homepage. It had something to do with Earth Day, I think… So, according to Google, black backgrounds don’t help, I think… haha… 🙂
    _________________________________________
    Actually it does work but on old cathode ray tube monitors and not so much on the plasma screens that are normal now.
    SA

  10. There are around 18 different versions of “black google” online. The best one I’ve found is http://www.cleanblack.com. Cleanblack is the only version that allows you to change the text colors of the google search results. Try it yourself by going to http://www.cleanblack.com/theme/