Why is it that when companies (even google) respond to these kinds of accusations I jut automatically cringe?
UPDATE: Google responds, claiming the Wissner-Gross estimate “is *many* times too high”: “Queries vary in degree of difficulty, but for the average query, 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 … In terms of greenhouse gases, one Google search is equivalent to about 0.2 grams of CO2.”
Still, the numbers add up. Google says “the average car driven for one kilometer … produces as many greenhouse gases as a thousand Google searches.” That means that the billion searches Google is estimated to do a day are equivalent to driving a car about a million kilometers. And that doesn’t include the energy used to power the PCs of the people doing the searches, which Google says is greater than the power it uses.