Tech giant Google—wealthy enough to have resources to pursue environmental leadership in whatever obscure place it may—has taken an odd step.

It has introduced a black background version of its search engine.

Yes, it's the same old Google. Just on black, instead of white.

Why?

A study from back in 2002 found that cathode ray tube (CRT) monitors expend significantly less energy to display black than white or other colors.

In January, a blogger riffed on this, postulating, in math that's since been refuted, that Google could save 750 megawatt-hours a year simply by changing the background color codes if its pages.

Google, in yet another of its infamous skunkworks projects, said 'why not,' and did it. Meet Blackle.

It's a cool move. But don't feel obliged to use it.

Liquid crystal displays (LCD) realize no savings from displaying black instead of white. The savings referenced above only apply to CRTs.

Sure, there are still huge numbers of CRTs in use today around the world. But we'll bet you're reading these very words, right now, on an LCD monitor.

And if that's the case, you don't need Blackle.

Want to really lower the planet's computing power consumption? Convince anyone still using a CRT to move to an LCD. That'll have a greater effect than the self-flagellation of forcing yourself to squint all day reading grey on black.

Of course, then you'll have to grapple with the karma of disposing of a perfectly good piece of computing hardware. And that's a whole other issue.