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Carbon cost of Googling revealed 'Carbon cost' of Google revealed
(about 3 hours later)
Two search requests on the internet website Google produce as much carbon dioxide as boiling a kettle, according to a Harvard University academic. Two search requests on the internet website Google produce "as much carbon dioxide as boiling a kettle", according to a Harvard University academic.
US physicist Alex Wissner-Gross has conducted research into the environmental impact of "googling". US physicist Alex Wissner-Gross claims that a typical Google search on a desktop computer produces about 7g CO2.
Environmental physicists are worried about the environmental impact of information technology. However, these figures were disputed by Google, who say a typical search produced only 0.2g of carbon dioxide.
In a statement, Google said it took the issue "seriously", adding "the energy used per Google search is minimal". A recent study by American research firm Gartner suggested that IT now causes two percent of global emissions.
A recent study estimated the global IT sector generated as much greenhouse gas as the world's airlines put together. Dr Wissner-Gross's study claims that two Google searches on a desktop computer produces 14g of CO2, which is the roughly the equivalent of boiling an electric kettle. If you want to supply really great and fast result, then that's going to take extra energy Dr Alex Wissner-Gross
Mr Wissner-Gross's study found a typical Google search on a desktop computer produces about 7g (0.25oz) of carbon dioxide.
If you enter another request you obviously end up with double that amount, which is the roughly the equivalent of boiling an electric kettle for a cup of tea.
Carbon emissionsCarbon emissions
The Harvard academic argues that these carbon emissions stem from the electricity used by the computer terminal and by the power consumed by the large data centres operated by Google around the world.The Harvard academic argues that these carbon emissions stem from the electricity used by the computer terminal and by the power consumed by the large data centres operated by Google around the world.
Although the American search engine is renowned for returning fast results, Mr Wissner-Gross says it can only do so because it uses several data banks at the same time, producing more carbon dioxide than some of its competitors on the net. Although the American search engine is renowned for returning fast results, Dr Wissner-Gross says it can only do so because it uses several data banks at the same time.
Mr Wissner-Gross says for every second we stay connected to the internet, we produce 0.02g of carbon emissions. Speaking to the BBC, he said a combination of clients, networks, servers and people's home computers all added up to a lot of energy usage.
This may not sound like a lot but each day an estimated 200 million internet searches are carried out. "Google isn't any worse than any other data centre operator. If you want to supply really great and fast result, then that's going to take extra energy to do so," he said.
In a statement, Google said that as computers became a bigger part of more people's lives, they consumed an increasing amount of energy - "and Google takes this impact seriously". Dr Wissner-Gross said he was working on a website called co2stats.com which helps companies identify "energy inefficient" aspects of their websites.
It said it had designed and built "the most energy efficient data centres in the world". In a statement on its official blog, Google said that Dr Wissner-Gross' figures were "many times too high."
"In fact, in the time it takes to do a Google search, your own personal computer will use more energy than we will use to answer your query." The firm said that a typical search returned a result in less than 0.2 seconds and that the search itself only used its servers for a few thousands of a second. This, said Google, amounted to 0.0003 kWh of energy per search - equivalent to 0.2g of CO2.
"We've made great strides to reduce the energy used by our data centres, but we still want clean and affordable sources of electricity for the power that we do use," said Google in its statement.
"In 2007, we co-founded the Climate Savers Computing Initiative. This non-profit consortium is committed to cutting the energy consumed by computers in half by 2010 and so reducing global CO2 emissions by 54 million tons per year. That's a lot of kettles."