Carbon cost of Googling revealed
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".
Environmental physicists are worried about the environmental impact of information technology.
In a statement, Google said it took the issue "seriously", adding "the energy used per Google search is minimal".
A recent study estimated the global IT sector generated as much greenhouse gas as the world's airlines put together.
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.
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.
Mr Wissner-Gross says for every second we stay connected to the internet, we produce 0.02g of carbon emissions.
This may not sound like a lot but each day an estimated 200 million internet searches are carried out.
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".
It said it had designed and built "the most energy efficient data centres in the world".
"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."