Screen Colours and Energy Consumption

It is a little known fact that different colours displayed on your PC screen consume different amounts of energy. Most people—even the most energy conscious and environmentally responsible—are completely unaware that different colours consume energy at different rates.  On a Cathode Ray Tube (CRT) computer monitor, for example, the colour black consumes 25% less electricity than the colour white.  Knowing this can help you make even better and smarter choices that will both save you money and help protect the environment.

Thanks to the Department of Energy, we now know the precise electrical impact of each of the 16 main colours used on Windows computers when appearing on the screen as a solid colour, those being:

Now, you don't want to overcompensate and make the mistake of applying this information to the extreme by, for example, viewing all printed text on your screen in white lettering on a black background (instead of the reverse, which is the obvious norm), as reading text this way can cause eyestrain after a while.

There are, however, many default colour schemes built into Windows (and Mac, for that matter) from which you can choose, so why not opt for a palette that predominantly uses colours from the less energy-demanding end of the colour spectrum?

Environmentally conscious web-designers will also appreciate having this handy palette of the most electrically-efficient colours (beyond the above-mentioned 16) to use as a reference in their work:

Emergy-C: The eco-friendly web-design colour-palette.

Another way to use this newfound knowledge to save money and energy is to use only a black screensaver. Now that you know about computer screen colour energy consumption, just think how much more energy those colour-rich, kaleidoscopic, photo-realistic screensavers are eating.  Sure, the money you'll be savings amounts to pennies - but that's not really the point. A little bit adds up, whether it’s money or energy, especially when you consider that you won’t be alone in your efforts. Every person who acts on these suggestions makes a difference. And the more people who do it, the bigger the difference.

You may already have been aware of some other display-related factors that affect energy consumption such as the following:

Hopefully, you’re already taking advantage of your computer's built-in power management controls, and now you also have this new energy-saving tip to add to your bag of tricks.

Just keep in mind that all of the above information relates specifically to CRT monitors. One way that you can instantaneously skirt all these issues and level the playing field of the energy consumption of colours is to switch to an LCD monitor. On LCD monitors, all colours use up the same amount of energy.

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