The Carbon Footprint of a Google Search

As innocuous as it may seem, "Googling" apparently has a definite environmental impact.

A story in The Sunday Times says that two Google searches are the equivalent to boiling enough water for one cup of tea.

Alex Wissner-Gross, a physicist at Harvard University who came up with the figures, estimates that a search on Google generates 7g of CO2. Boiling a kettle for just one cup of tea generates 15g of CO2.

With an estimated 200 million searches on the Internet daily there's obviously a great amount of concern regarding the environmental impact of web search. If all those searches were on Google (with it's supposed 7g/query) then that would be the equivalent to over 1,500 tons of carbon dioxide emissions, or over 9 million cups of tea!

According to the story Google does not, apparently, publish the figures on its energy consumption or its carbon footprint, but they are just one part of the global IT industry which technology analysts Gartner believe to be as polluting as aviation.

The blame for Google's carbon output is laid squarely at users' desire for quick and accurate searches - the amount of processor power needed from multiple datacentres in order to satisfy search demands is apparently pretty phenomenal and one researcher in the Times story says that

Data centres are among the most energy-intensive facilities imaginable

That's quite a dramatic statement.

But at the end of the very same day that story was published, Google posted on the Official Google Blog to correct these figures, adding that they believe they have the most energy-efficient data centres in the world.

Google state that with a fast Google search taking 0.2 seconds their results use only 0.2g of CO2. That's 35 times less than Wissner-Gross's figure, a considerably smaller amount.

If all search only generated that amount of carbon dioxide on a daily basis then our previous example would be greatly reduced to less than 50 tons of CO2 daily and a little over 250,000 cups of tea.

So, who's right? Google, who dominate the arena as the world's favourite search engine or Alex Wissner-Gross's research with his commercial service?

If and when we find out we'll let you know but, after I've Googled for an energy-efficient kettle and green hosting, my tea should be brewed ;)


Frankly, I had never considered the impact of my very frequent searches, so I can only hope that the Google figures are right. Seemingly, we may have to start pondering other conservation measures....limiting the number of free searches, for example? Kind of wild; my current mindset is that the internet and its resources are vast and limitless....

BTW, it would be cool to convert the energy example into "American-speak"...not too many of us have electric kettles, much less regularly drink tea....