Can a web page's background color save electricity?
I have some input with regards to the claim that the color black uses less electricity. This claim is TRUE for CRT monitors (the big old clunky ones) but is FALSE for LCD monitors (the thin kind that come with laptops and newer desktops).
BLACK USES THE SAME OR MORE ELECTRICITY ON LCD MONITORS, NOT LESS. This is backed up on the FAQ from the original site that posted the power savings calculations . This is because of the way an LCD works which is approximately opposite of a CRT -- an LCD (think laptop or digital watch) has a backlight that is on all the time and electricity is used to change pixels to COVER the white backlight . The more, darker pixels you show, the more electricity you use to cover them. A CRT (think desktop computer or old tv) works in the opposite fashion, showing black by default and shooting electrons towards a fluorescent screen which then lights up .
My own trials viewing google.com and blackle.com and measuring immediate watts via my trusty Kill-A-Watt(tm) electricity meter:
|CRT||108w||79w||-29w||20" Sony Trinitron|
|LCD||21w||22w||+1w||Dell Latitude D820 laptop
While blackle saved (significant) electricity on my desktop, it used MORE electricity on my laptop, not less. Also note that the CRT viewing blackle still uses almost 4x the electricity than the LCD viewing google.
I'm glad to see that the folks at the HoS are serious about saving electricity; if you're still using a CRT monitor then by all means, use as many black backgrounds as possible. However, if you use an LCD monitor (the flat kind) you should stick with regular old google.com with a light background.
Some other simple things you can do to conserve electricity while using your computer: