In January 2007 a blog post titled Black Google Would Save 750 Megawatt-hours a Year proposed the theory that a black version of the Google search engine would save a fair bit of energy due to the popularity of the search engine.
So Blackle was created. Blackle searches are powered by Google Custom Search
Blackle saves energy because the screen is predominantly black. "Image displayed is primarily a function of the user's color settings and desktop graphics, as well as the color and size of open application windows; a given monitor requires more power to display a white (or light) screen than a black (or dark) screen."
Spread the word about Blackle by telling your friends and family to set it as their home page. If you have a blog then give it a mention.
www.blackle.com
*EDIT*
Extract from an article about Blackle I read in the newspaper Athens Voice.
"There are two kinds of pc screens. CRT and TFT (the thin ones that we all use now). TFT are basically consisted of 2-3 fluorescent lamps put behind from a liquid crystal on which appear the images we are viewing. When we see white the liquid crystal is inactive and the light flows within it. When we see black, the liquid crystal is active and and blocks the light from the fluorescent lamps to reach our eyes. In both cases the most energy spending part of a flat TFT screen (which is the fluorescent lamps) are active. The fluorescent lamps are inactive only when we turn off the screen completely.
[...] As for the CRT screens it is true that they consume a bit less electrical power when they show black, but the ones that really care about saving energy shouldn't have one of these at all, because CRTs consume about 200-300 watt per hour when TFTs consume roughly 40-60 watt. In that case the amount of electrical power saved from blackle.com is close to zero in comparison to the consumption mentioned above."
I found that article very interesting and illuminating and since I own a TFT screen I'm ready to switch back to normal google.com
The only thing that I liked about blackle was that the black color is less tiring for my eyes.
I tried to translate the article as faithful to the original as I could, hope you found it interesting too (if someone bothered to read so far
).