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, according to new research.
While millions of people tap into Google without considering the environment, a typical search generates about 7 grams of CO2. Boiling a kettle generates about 15 grams.
"Google operates huge data centers around the world that consume a great deal of power," said Alex Wissner-Gross, a Harvard University physicist whose research on the environmental impact of computing is due out soon. "A Google search has a definite environmental impact."
Google is secretive about its energy consumption and carbon footprint. It also refuses to divulge the locations of its data centers. However, with more than 200 million Internet searches estimated globally daily, the electricity consumption and greenhouse-gas emissions caused by computers and the Internet is provoking concern.
A recent report by Gartner, the industry analysts, said the global IT industry generated as much greenhouse gas as the world's airlines — about 2 percent of global CO2 emissions.
"Data centers are among the most energy-intensive facilities imaginable," said Evan Mills, a scientist at the Lawrence Berkeley National Laboratory in California. Banks of servers storing billions of Web pages require power.
Though Google says it is in the forefront of green computing, its search engine generates high levels of CO2 because of the way it operates. When you type in a Google search for, say, "energy saving tips," your request doesn't go to just one server. It goes to several competing against each other.
It may even be sent to servers thousands of miles apart. Google's infrastructure sends you data from whichever produces the answer fastest. The system minimizes delays but raises energy consumption.
Google has servers in the U.S., Europe, Japan and China.