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Google Says Adding Dark Mode To Apps Saves Battery (betanews.com)

Posted by msmash on from the closer-look dept.

Dark Mode is not just more aesthetically pleasing to many people, there are real battery-life boosts to be had -- and Google has the numbers to prove it. From a report: Touting the benefits of Dark Mode, Google showed that with screen brightness set to 50 percent, using YouTube with Dark Mode enabled resulted in 14 percent less battery usage. With screen brightness set to 100 percent, the saving jumps to 60 percent. These are not numbers to be sniffed at, but the biggest savings are to be seen on phones with AMOLED screens as anything that is black does not require pixels to be powered. Slides from the event show Google comparing the power usage of its own Pixel phone with an LCD iPhone 7. It shows a 63 percent battery saving when displaying a screenshot of Google Maps in normal and night mode.

29 of 61 comments (clear)

  1. Here's my question by slashmydots · · Score: 2

    Aren't normal screens backlit by an LED array and they're on constantly and black pixels just blocks and absorb or reflect the light? So making an app all black would simply make your phone warmer and the only solution is dimming it?

    1. Re:Here's my question by slinches · · Score: 3, Interesting

      They are backlit, but many new displays will dim or turn off the backlight in darker regions of the screen.

      --
      Knowledge Brings Fear
    2. Re: Here's my question by Anonymous Coward · · Score: 1

      AMOLED screens, such as those Samsung uses, do not have a backlight.

      It's why Samsung has massive screens and always on screen features without obliterating battery life.

      They are also better looking.

    3. Re:Here's my question by EvilSS · · Score: 2

      They are backlit, but many new displays will dim or turn off the backlight in darker regions of the screen.

      Are there any phones doing local dimming? Aren't the majority of LCD screens on phones edge lit?

      --
      I browse on +1 so AC's need not respond, I won't see it.
    4. Re:Here's my question by Anonymous Coward · · Score: 1

      OLED is per-pixel dimming.

    5. Re:Here's my question by fluffythedestroyer · · Score: 1

      To my understanding, LED when the color is black should require less or no power

    6. Re:Here's my question by ceoyoyo · · Score: 5, Informative

      LCD screens yes. Google is talking about their phone with an OLED screen. In OLED screens each pixel actually emits light, so turning it off (or down) saves energy.

    7. Re:Here's my question by infolation · · Score: 2

      Therefore we should watch films on our devices that are set predominately at night like Michael Mann's The Keep & Collateral, David Fincher's Se7en, Alien Vs Predator and The Evil Dead '91.

    8. Re:Here's my question by thegarbz · · Score: 1

      Actually LCDs save power too. The backlight is constant but most common LCD technologies will actually use energy to block the light away from its default transparent arrangement.

    9. Re:Here's my question by thegarbz · · Score: 1

      Aside from the fact that a large portion of phones on the market use OLED displays, and they consume power only to light up individual pixels having no backlight, you are right while you don't understand why.

      On an LCD you block light to make pixels black, this incidentally uses power, when the power is released the LCD becomes transparent. That said it isn't really relevant, it's a minor difference in power compared to an OLED panel.

    10. Re:Here's my question by ceoyoyo · · Score: 1

      LCDs use energy to twist the crystals and change the polarization. It's pretty arbitrary what the rest state is, but when I looked previously it seemed like most LCDs were set up for a default light blocking state. Might have changed of course, but it would seem to make sense to orient the polarizer so the rest state was whatever used the least energy on average.

    11. Re:Here's my question by KiloByte · · Score: 1

      I found a claim that new monitors started doing this around 2005, and that (post from 2013) "the majority of monitor sales" do this. So, it's good to have on real computers, too.

      I'd thus like to advertise a nice GTK2+3 theme: you want to "apt install darkcold-gtk-theme" (or darkmint if you prefer green). Despite no css skills I fixed them up, and since then the original author returned from years of no show. Somehow, any other theme shipped in Debian is at most mid-gray rather than actual black.

      --
      The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
    12. Re:Here's my question by hawk · · Score: 1

      you can usually tell by looking when it's powered off.

      In high school, when a TI-30 (?) was the basic thing most had for Physics, we discovered that one of the variants had a case that would pop open easily.

      We would grab an unwatched phone, hide behind one of those dinosaurs that still walked the earth, and flip the display--giving our victim white numbers on a black background.

      Then we'd do something innocuous to get him to look at the calculator, and enjoy the ensuing panic . . .

      hawk

    13. Re:Here's my question by KiloByte · · Score: 1

      Unless you're using an OLED display, or one with local dimmin, a dark theme does nothing to save energy

      Right then. A dark theme is still good for your eyes during the night, so you save wetware even if no electricity.

      --
      The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
  2. Re:Why not offer the alternative up front? by Anonymous Coward · · Score: 1

    Not dark mode. Take the glaring blinding white of Google's home page makes it impossible to use inside a moviehouse or place of worship...

    I have a better alternative up front.

    Don't use your fucking smartphone inside a moviehouse or place of worship.

  3. Re:Genius by DontBeAMoran · · Score: 1

    +1 million informative.

    --
    #DeleteFacebook
  4. Whoooo...Caahh... by xsspd2004 · · Score: 3, Funny

    Behold, the lack of power of the dark mode.

    --
    This is not an illusion, a rip-off, or a ninja technique!
  5. Duh by azcoyote · · Score: 2

    Now why has Google been burning my eyes and draining my batteries for years with their excessive use of all-white UXs?

    --
    Incipiamus, fratres, servire Domino Deo, quia hucusque vix vel parum in nullo profecimus.
  6. Re:Why not offer the alternative up front? by gerald.edward.butler · · Score: 1

    Yeah, but, can I eat popcorn and slurp a giant soda in church and stand up, raise my hands, and "speak" in tongues in a movie house? No? Then, why are you equating these two things?

  7. NO SHIT, SHERLOCK. by Anonymous Coward · · Score: 1

    Thanks for admitting your design team is being run by retards.

  8. Black Pixels by CanHasDIY · · Score: 1

    Whether or not black pixels save energy is the technological equivalent of the "are eggs healthy" debate:

    CRT screen? Black saves energy over white by not firing the beam at the dark pixels.

    LCD screen? White saves energy over black by not diffusing the backlight.

    OLED/AMOLED screen? Black saves energy by not lighting the pixel.

    So will the next revolution in display technology swing the pendulum back?

    --
    An enigma, wrapped in a riddle, shrouded in bacon and cheese
    1. Re:Black Pixels by thegarbz · · Score: 1

      LCD screen? White saves energy over black by not diffusing the backlight.

      Wrong. Most LCD configurations are transparent without energy and block light when energy is applied. The difference is only slight compared to OLED / CRT (unless you have a HDR display where the backlight adjusts depending on the content) but none the less black is actually the energy saving state not white.

  9. Google late to the party by thegarbz · · Score: 2

    Google finally realises what Samsung users have known about for over 8 years thanks to a long history of using OLED displays.

    Seriously the energy saving benefits on not lighting the screen up actually made it into Samsung's variant of Eclair back in the day which gave you the option to use a dark mode or invert the display.

  10. Dark backgrounds... by DriveDog · · Score: 1

    ...are good with me. I've always hated white backgrounds and dark text/objects, on any screen, small or large. More eyestrain, less distinct objects/letters/whatever. So fine, make all the blank areas black. BTW, how do I get Slashdot to use a grey background???

  11. Google Homepage by WankerWeasel · · Score: 2

    And yet their homepage is still white. A blog post some years ago calculated that a black Google homepage would save 750 megawatt-hours a year. http://ecoiron.blogspot.com/20...

    1. Re:Google Homepage by jafffacake · · Score: 1

      http://www.blackle.com/

  12. dark google - blackle ! by jafffacake · · Score: 1

    Does anyone remember http://www.blackle.com/ ?

  13. Um, duh? by sremick · · Score: 1

    Why is this news? We've known this for years:
    https://www.greenbot.com/artic...

    What next? We need Google to announce that water is wet so that people can finally go jump in a lake?

  14. Re:Pixel 3 vs iPhone 7 by Anonymous Coward · · Score: 1

    They compared the ORIGINAL Pixel to the iPhone 7, not the Pixel 3. Both phones came out in 2016, just one month apart. Please learn how to read before you start jerking your knee, you illiterate, raging fanboi.