

A recent report by a Harvard physicist estimates that a Google search generates about seven grams of carbon dioxide based on the electricity required to keep the company's servers running.

The headlines about the study quickly proliferated around the globe, with Britain's Inquirer chiding, "Googling pollutes the planet." Well, sure, but so does just about every other human activity. And it is in that context that Googling and internet usage must be judged.

In short, Googling is not the issue, dude.

Today, Google said that each of its searches uses 1 kilojoule or 0.24 kilocalories of energy. We can convert that into a unit we're all more familiar with: gas for your car.

A gallon of gas contains about 31,000 kilocalories — about 115 Snickers bars' worth — of energy, so a single gallon of gasoline would power about 130,000 searches. Even if Google handled five billion searches per day, the company's energy consumption for searches would be equivalent to something like the burning of 39,000 gallons of gasoline. The United States alone consumes 390,000,000 gallons every single day!

And even U.S. gas consumption is just a small fraction of the world's total energy usage — something like 1.4 exajoules of power per day. That's 1.4 times 1015 kilojoules. So, even if Google consumed 5 billion kilojoules for searches every day, that would only require 0.00037 percent of the world's daily energy usage.

As for the carbon footprint, Google says each search is only responsible for 0.2 grams of CO2, not the 7 grams that the Harvard researcher claims, but the dispute misses the larger point. U.S. greenhouse gas emissions are estimated at 16.9 billion kilograms of CO2-equivalent per day. Again assuming 5 billion daily searches, Google would be responsible for either 0.2 or 0.006 percent of the nation's carbon footprint, depending on whose number you choose.

When it comes the world's energy system, Google is not the problem. They are, however, embedded in the energy-intensive infrastructure that we've been building ever since we figured out how to tap the earth's fossil fuel resources.

It is a fine thing if internet companies want to worry about their carbon footprints. It's great, in fact. But chiding Google for making such a relatively tiny contribution to the overall environmental problem in the world is like complaining about a wobbly leg on one of the deck chairs on the Titanic.

Image: Gayle Laakmann

See Also:

WiSci 2.0: Alexis Madrigal's Twitter , Google Reader feed, and project site, Inventing Green: the lost history of American clean tech; Wired Science on Facebook.