Climate Feedback

Google turns to the dark side

Olive Heffernan

Apparently, an all white computer screen, such as an empty Word page, or the Google page, uses 74 watts to display, whereas a black screen consumes only 59 watts. So claimed Mark Ontkush in a post on the ecoIron blog in January. Doing a few back of the envelope calculations based on numbers of users per day and wattage for different coloured screen from EnergyStar, Ontkush figured that the energy saving would be 750 Megawatt hours per year if Google had a black screen.

And so, with the help of Heap Media, Google created a black version of its search engine, called Blackle.

The Wall Street Journal did some of their own calculations, which challenge the energy-saving claims of Blackle. In a blog post from May, they point out that the “savings are most likely to accrue from older CRT (cathode-ray tube) monitors, rather than the more modern, energy-efficient LCD (liquid crystal display) screens that dominate the market (representing three quarters of all monitors world-wide as of last year, by some estimates).” They did some tests using Blackle, Google and the New York Times on a CTD and LCD monitor and found the difference “so slight as to be within the margin of error for the power meter”.

Since then, it’s been blogged about here, here and here. Anyhow, check it out – it’s certainly novel, whether or not it’s especially efficient.

Olive Heffernan

News Editor

Nature Reports Climate Change


  1. Report this comment

    Andy said:

    When are you changing to a black background? Nice to throw stones, but not in your own glass house, eh?

  2. Report this comment

    Tanmoy Hazra said:


    This is really a good thing which we all get some innovative ideas from Google.

    The electricity consumption calculation seems to be perfect but my concern will that be human-eye friendly.

    Does it have any negative effect on our eye on long run?

    I still believe Google might have already considered these points…if not, these could be a major concern on viewer and may lead to major fall-out of surfing rate of Google site.



  3. Report this comment

    Sergey Solyanik said:

    Most displays are LCD now. LCD backlight is always on, and it’s more power needed to do the black pixels, to energize crystals.

  4. Report this comment

    Jeff Johnson said:

    You guys are not looking at the big picture. If I look at a black screen all day I am going to get seriously depressed. That means I will get in my car and drive to a doctor. Possibly several. Now think of all the CO2 I just dumped in the air due to this black screen. A crime.

  5. Report this comment

    grubi said:

    Most displays are LCD now? In what universe are you living? Most displays you see, perhaps, but CRTs still outnumber LCDs by a huge margin.

    Let’s not try to give in to hyperbole.

  6. Report this comment

    Bill Binko said:

    Actually, the key thing to realize is that the site ( is actually just a Google Co-op site meaning that it was developed completely without Google’s involvement and 100% for the benefit of it’s owners.

    The way Co-op sites work is this:

    1) Authors put together a simple search form on their site. The form submits to Google

    2) Google returns their search results along with text ads

    3) Any revenue from those ads are split between Google and the site owner.

    So, regardless of whether dark backgrounds are good for the environment, using will enrich its owners. That’s fine with me, but it would be nice to have that out front instead of making this look like a Google “doing well by doing good” thing.

    If you really want to use a dark background, I suggest using which works exactly the same was, has a dark background and gives 100% of its revenue to kids with congenital heart defects.


  7. Report this comment

    Waldo Jaquith said:

    You are incorrect in writing that “Google created a black version of its search engine, called Blackle.” In fact, Google had nothing to do with it. Some guy just put up a black page with a single form field that submits to Google. Doing so requires no involvement from Google whatsoever and, in fact, did not.

  8. Report this comment

    gordonyb0 said:

    According to your theory,you should change your background into a darker one.

    but still very glad to see this passage. Well done!

  9. Report this comment

    May said:

    At least it looks cool, even if it’s not really helpful…

  10. Report this comment

    meany said:

    I wish blackle or some other dark search engine with google’s power had image search capability.

    > You guys are not looking at the big picture.

    > If I look at a black screen all day I am going to get seriously depressed.

    1. Nobody’s forcing people to use it.

    2. You can force all websites to be any color scheme you want in Display Properties > Appearance > Window, and Internet Options > General > Accessibility > Ignore All. Creating a custom CSS file to load in your browser also helps.

    3. You’d have to be a truly weak and pathetic individual to be brought down by a black screen.

  11. Report this comment said:

    Don’t turn on the lights says Google!

    With the world conserving energies right left and center it comes as no surprise to see our very own favorite search engine Google go Blackle! Yes that’s exactly what the black version of its search engine is called. Now that I have already set the …

  12. Report this comment

    Jason said:

    If people have trouble reading light text on a black background, then maybe using Greygle is an option it uses a grey background with a dark color text as a compromise between energy savings and readability. But as for Jeff, I am not sure which would get him depressed more quickly. Perhaps we can run an experiment with him. Have him view Blackle all day and then Greygle the next and see which one makes him want to go to the doctor more.

  13. Report this comment

    blacky said:

    On a backlit LCD, the effect is the same as covering a light bulb with a black towel. Does that save energy? If yes, I’ll apply this to all my light bulbs and you may call me blacky.

  14. Report this comment

    Bill Binko said:

    In response to your reader’s comments, has implemented a new feature that allows you to choose your colors by subtly changing the URL of our search page.

    The format is:


    Any valid CSS or HTML color is acceptable. For example, ‘white’, ‘black’, ‘yellow’, or any 3 or six digit Hex code (without the #) such as ‘400’ (dark red) or "552222’ (an ugly pinkish gray!).

    The system will try to determine whether the text should be white or black.

    If you want to specify the foreground as well (why not!) just use this format:


    So, you can use

    to get White text on a black background.


    to get a yellow on dark gray.



  15. Report this comment

    Krista said:

    I really liked this idea ever since I first heard of it. Since I do have a CRT monitor, I thought it would be a way to save energy and help the environment without even leaving my desk. Although Blackle is the most popular of these sites, I actually prefer doing searches on a site called Greenback Search ( whose search engine is powered by Google so you get the same results. They use eco-friendly colors but more importantly they purchase carbon offsets on behalf of users when searches earn revenue. Check the site out, it has other really nice features as well.

  16. Report this comment

    Yury Zammit said:

    I do not think that using black or white background screens will do any difference in terms of power consumption. I have followed this issue for some time and found the following post that discredits the whole ‘Black Google’ issue see: Read it and make your own conclusions.

  17. Report this comment

    Norris said:

    Wow! After reading the “dark” insights above I have a suggestion for you. You can also obtain a dark screen by turning it off. Then you could go outside and get acquainted with the world.


  18. Report this comment

    PSU Calculator said:

    This idea was used by at least a few search engines in the past and I believe there are a few blogs that use the same black background and style.

    I like it, it’s just an innovative way to look at things.

  19. Report this comment

    abbasi said:

    No doubt, a lot of energy can be saved by turning Google to black screen, but we should also take the usability factor into consideration. Current outlook is quite user friendly.

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