The Carbon Footprint of a Google Search?

Last year, The Sunday Times published an article based on research by Alex Wissner-Gross calculating the CO2 emissions of internet searches.

The article claimed that one Google search generates about 7g of CO2 (about half the carbon dioxide produced by boiling an electric kettle). Google responded and said the numbers were more like 0.2g of CO2 per search, which is quite a bit less.

This discrepancy can partly be explained when you take into account the length of time a search takes. A simple one-hit search would be on the low end of the spectrum, whereas a search that requires several attempts would obviously require more computer brain-power. Whatever the exact numbers, the important thing to be aware of is the impact your internet use has on the environment; even a Google search that takes 0.2 seconds to complete.

Google's lightning fast search engines are powered by servers all over the world, including Europe and Japan. A search request travels across more than one server, which means data can travel thousands of miles and use up energy on many networks before it arrives to your computer. Once again, it boils down (no pun intended) to powering and cooling data centres.

A data centre is a network of machines that run 24/7, storing and serving information. These computers also give off a lot of heat, so it's necessary to cool them, using even more energy. The primary source of this energy is coal and less than 10% is from renewable sources.

Our computer habits generate about as much greenhouse gas emissions as the airline industry. Obviously this doesn't mean that checking your email impacts the environment quite like a flight to the tropics does. But it's necessary to consider that although most of us don't fly every day, we probably check our email and "Google it" every day.

Over and above our efforts to reduce energy consumption with personal computer use, we can also extend into thinking about the overall impact of our internet activity.

http://www.newstatesman.com/culturetech/2010/06/co2-energy-google-industry
http://googleblog.blogspot.com/2009/01/powering-google-search.html
http://www.timesonline.co.uk/tol/news/environment/article5488934.ece