The cloud begins with coal
Big data, big networks, big infrastructure- An overview of the electricity used by the global digital ecosystem
A study by Digital Power Group
The information economy is a blue-whale economy with its energy uses mostly out of sight. Based on a mid-range estimate, the world’s Information-Communications-Technologies (ICT) ecosystem uses about 1,500 TWh of electricity annually, equal to all the electric generation of Japan and Germany combined — as much electricity as was used for global illumination in 1985. The ICT ecosystem now approaches 10% of world electricity generation. Or in other energy terms – the zettabyte era already uses about 50% more energy than global aviation. This recent study (August 2013) by Digital Power Group includes interesting facts about the use of electricity by smart phones and tablets.
You can read the complete paper at : http://www.tech-pundit.com/wp-content/uploads/2013/07/Cloud_Begins_With_Coal.pdf?c761ac&c761ac.