Best known for its internet search engine, Google is also the owner of sites such as the video specialist YouTube, which require huge numbers of data servers to keep up with consumer demand.
To store the information that drives its business, Google has set up so-called "server farms" in a range of locations. Large amounts of water are needed to cool the servers.
Google revealed in 2011 how energy was used to power its web services – 260 million watts continuously across the globe, or roughly a quarter of the output of a standard nuclear power plant – and said 25 per cent of its energy was supplied by renewable fuels.
In 2012 the New York Times published the results of an in-depth investigation it carried out into data centres. It quoted a Stanford University study which showed that data centres in the United States accounted for two per cent of all electricity used in the country in 2010. The newspaper also noted that data centres can waste 90 per cent of the electricity they pull off the grid and are seen by authorities as a source of pollution.
(All pictures: Google.com)