We’ve all been sent this e-mail...
If Google had a black screen, taking into account the huge number of page views it receives, an estimated 750 mega watts/hour per year (sic) would be saved.
With this in mind, Google has created a black version of its search engine called Blackle, which functions in exactly the same ways as its white version, but consumes far less energy. Help to spread the word, use: www.blackle.com
Firstly, that page was not created by Google but by an entirely different company. Blackle is simply hooking into Google’s search engine.
More importantly, other than the warm, tingly sensation you get when you feel that you have done something good, which is disputable in this case, there are few benefits to this proposal. As such, I find this article rather misleading.
The proposal would be appropriate if we were all using old CRT screens but with LCDs, the power usage is constant, with most of the power being used by the back lighting. Mere microvolts are needed to activate the actual liquid crystals in the case of a wristwatch or calculator, so with no back light, a small 1.5 Volt battery powering a watch or calculator can last several years. Similarly, the power used to run a CRT TV for one night would be enough to keep your LCD watch running for several generations. Making a LCD screen black does not use any less back light, unless it is made black by turning down the brightness, but that would be pointless as then you would not be able to see anything.
If anyone really wanted to save energy, it would probably make more sense to promote LCDs over CRTs, as they are generally more power-efficient. Google has been in the limelight for a while on the subject of energy consumption, and I am convinced that they would have better results if they focused their attention on reducing the power consumed by their servers.
Another though – why not search less? Every search you do contributes to the power consumption of Google’s servers, so fewer searches would probably save a lot more power than a black background. Don’t you think?
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