Google’s carbon footprint

According to the official Google blog, one Google search uses about 0.2 grams of carbon dioxide, roughly the same amount of energy your body burns in 10 seconds.

The search engine’s energy expenditure came into question after a Sunday Times of London story on Jan. 11 reported that “performing two Google searches from a desktop computer can generate about the same amount of carbon dioxide as boiling a kettle for a cup of tea,” or seven grams of CO2 per search. The claim was based on research by Harvard University physicist Alex Wissner-Gross about the environmental impact of computing.

However, a day after the story ran, Wissner-Gross told TechNews World, “Our work has nothing to do with Google,” and his study doesn’t mention the company. “Our focus was exclusively on the web overall, and we found that it takes on average about 20 milligrams of CO2 per second to visit a website.” As for the teakettles, that was also a comparison devised by the Times.

However, Wissner-Gross says a Google search does have a “definite environmental impact.” “Everything online has a definite environmental impact,” he told TechNews. “I think everybody can agree on that, including Google.”

Adding to the dialogue about the IT industry’s environmental footprint is that more traditional forms of getting information—mailing letters, copying documents, driving to the library, etc.—also require significant energy expenditure.