January 22, 2009
Regarding ‘Google’s carbon footprint exposed‘:
It was literally a tempest in a teapot. When a critic recently suggested that two searches on Google consumed as much energy as boiling a kettle for a cup of tea, even many of us within the company were startled. Could this really be the case? Rather than consulting the tealeaves, we took a fresh look at the facts.
Not long ago, answering a query meant travelling to the reference desk of your local library. Today, search engines enable access to immense quantities of useful information in an instant, without leaving home. Tools like email, online books, photos and video chat increase productivity while decreasing our reliance on cars, pulp and paper.
Of course, as computers become a bigger and bigger part of people’s lives, information technology consumes an increasing amount of energy, and Google takes this impact seriously. That’s why we have designed and built the world’s most energy-efficient data centres. These efficient centres reduce the energy required to conduct Google searches: your own personal computer consumes much more energy than Google needs to provide an answer.
It was claimed that a typical search uses “half the energy as boiling a kettle of water” and produces seven grams of CO2. Our research showed that this was many times too high.
Search queries may vary in degree of difficulty, but Google is fast – for the average query, the servers it touches each work on it for just a few thousandths of a second, returning a search result in less than a fifth of a second, meaning a single Google search generates only around 0.2 grams of greenhouse gas (or around 1kJ of energy).
This is a very small amount. The average adult needs about 8000 kJ a day of energy from food, so a Google search consumes just about the same amount of energy that your body burns in ten seconds.
Some other comparisons may be helpful: it takes 2,739 Google searches to consume as much energy as a modern efficient washing machine uses to clean a single load of clothes: that’s a year’s worth of searches for just one load. It takes 322 searches to equal an hour spent watching TV, and the average car driven for one kilometre produces as many greenhouse gases as a thousand Google searches.
We were interested to learn that the Harvard physicist on whose research the stories were based was equally surprised by the purported figures. Alex Wissner-Gross explained that his focus was not on Google but on the web as a whole, and he found that it takes on average about 20 milligrams of C02 per second to visit a website. Tea kettles? The research never mentioned it, Wissner-Gross said, and in any case, he is a coffee drinker.
Wissner-Gross later told InternetNews that “Google’s really the leader in this space and the largest in this space. They are also the thought leader in terms of green energy for large Internet platforms”.
We take energy issues very seriously. Our founders are passionate about combating climate change. We deploy bio-diesel shuttles and electric cars to and from our Mountain View, California headquarters, offer bikes for employees to ride from building to building, and depend on recyclable materials throughout our buildings. We’ve made great strides to reduce the energy used by our data centres and we want clean and affordable sources of electricity for the power that we do use.
Google has come up with its own plan to get the United States 100% off coal and oil for electricity generation by 2030 (read about it at google.com/energyplan.) We are partnering with General Electric to re-invent the global electricity grid to be both smart and big, and in the right places. The new grid must be smart to switch away from wind power when the wind stops blowing, and big to transfer solar energy captured in the far-off desert in our cities.
In 2008, our philanthropic arm, Google.org, invested $45 million in breakthrough clean energy technologies. We’re also working with other members of the IT community to improve efficiency on a broader scale. In 2007, we co-founded the Climate Savers Computing Initiative, a group which champions more efficient computing. This non-profit consortium is committed to cutting the energy consumed by computers in half by 2010 – reducing global CO2 emissions by 54 million tons per year.
Now that’s a lot of kettles of tea.
Google’s senior manager for communications in BrusselsAuthor : Andreas