We first documented Blackle’s existence about a month ago.  At the time, it was believed that CRT monitors would require less power to display the site’s black background, and new testing has confirmed that principle.  But the savings aren’t that impressive, and they’re lost when LCDs are in use.

“We applaud the spirit of the idea, but our own analysis as well as that of others shows that making the Google homepage black will not reduce energy consumption,” writes Bill Weihl, Google’s “Green Energy Czar,” on the Official Google Blog.  “To the contrary, on flat-panel monitors (already estimated to be 75% of the market), displaying black may actually increase energy usage.  Detailed results from a new study confirm this.”

Yet throughout the post, Weihl stresses the importance of efficiency, and he goes on to give several more effective tips (“turn down the brightness on your monitor” might be the least obvious of them).  And lest we all forget – saving energy helps the environment and your pocketbook.

It seems that Blackle’s not the best path to those savings, however.  A good searcher shouldn’t spend much time at the engine itself, anyway, and Blackle’s text is annoyingly difficult to read.

Blackle operates on the principle that displaying a black computer screen requires less energy than showing a white screen.  This only holds true when CRT monitors are involved, but “an all white web page uses about 74 watts to display, while an all black page uses only 59 watts,” according to Mark Ontkush.

Ontkush was cited two months ago in an article by TreeHugger about Blackle.  Since, then, Blackle has been mentioned by the Brisbane Times (an Australian publication), bigmouthmedia (a UK company), and the Hindustan Times (which is based in India) – word is definitely spreading.

And from a pure “search” standpoint, there’s no reason for it not to; Blackle’s design is very similar to Google’s, and the search results are identical.  Getting used to the gray-text-on-black-background is difficult, however, and many people (including your humble author) have found it harder to read then the traditional black-on-white.  Time wasted due to squinting may make up for the slight difference in power levels.

Still, given Google’s interest in conservation, it’s interesting to see what people have done with the engine in the environment’s name.