Google: We are not an energy hog

Faster than you can boil a cup of tea, Google's Urs Hölzle cooked up a response to a Harvard University researcher's accusation that Google searches adversely affect the environment. Hölzle's conclusion? The research is just a lot of hot air that doesn't put Google in any hot water.

In the U.K. Sunday Times, researcher Alex Wissner-Gross posited that two Google searches consumed as much carbon dioxide as boiling a kettle for a cup of tea, or about 7g of CO2. Wissner-Gross attributed the amount to the vast number of Google servers, many of which may be thousands of miles apart, used to complete each search. "The system minimizes delay but raises energy consumption," according to the Times article.

In his responding blog, Hölzle said the 7g figure was a bit overblown, and each Google query actually releases the equivalent of just 0.2g of CO2. While each search does use several servers:

"the servers it touches each work on it for just a few thousandths of a second. Together with other work performed before your search even starts (such as building the search index) this amounts to 0.0003 kWh of energy per search, or 1 kJ. For comparison, the average adult needs about 8000 kJ a day of energy from food, so a Google search uses just about the same amount of energy that your body burns in ten seconds.

So which is it, the energy to boil a kettle or that used by a body in 10 seconds? Neither and both. Those are really apples-to-oranges comparisons, since Wissner-Gross takes into account the user's PC, while Google focuses solely on the data center. But either way, a Google search consumes a lot less energy than driving to a library and researching the answer the old-fashioned way. OK, so maybe you can bike to the library. But that building needs to be heated/cooled. And what about all the trees used to make those cadres of phone directories and encyclopedias, all of which are out of date pretty much the moment they're printed? It's just a silly argument. While it's important to keep the idea of reducing data center and IT energy consumption on the front burner, picking on the carbon footprint of Google searches seems a tepid way to go about it.

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