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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