Google's Green Cred: A Storm in a Teacup?

A Harvard University physicist has left Google a bit hot under the collar with research claiming a couple of Google searches generate as much carbon dioxide as boiling the kettle.

Alex Wissner-Gross claims "Google operates huge data centres around the world that consume a great deal of power" and that "a Google search has a definite environmental impact." The Sunday Times reports that the nature of the company's search means it calls upon the power of several 'competing' servers for each search, which is believed to quicken its response rate but raise its energy consumption.

Wissner-Gross claims each search generates between 5g and 10g of CO2, while bringing a kettle to boil produces 15g. But these figures don't add up, says The Register.

Instead, it cites consumer champ Which magazine, which says that boiling a kettle results in something closer to 50 or 60g of emissions. The article goes on to explain that "bottomnal emissions" of methane gas should be of far more concern. Using Wissner-Gross's estimates, the Reg helpfully points out that "every three days of your life your guts are needlessly burdening the Earth with greenhouse gas destruction equivalent to doing a Google search."

Then there are the emissions generated by breathing...

So what's the verdict? One search = how much greenhouse gas?

The Official Google Blog says around 0.2g of CO2.

John Buckley of Carbon Footprint.com says between 1g and 10g (but running a PC generates between 40g and 80g an hour.)

Chris Goodall of Carbon Commentary (and author of "Ten Technologies to Save the Planet") says 7-10g (for 15 minutes on a computer).