ABSTRACT
The modern world's reliance on computers and the internet depends upon the deployment of huge numbers of specialised computers called servers which store data and may respond to queries sent via a network or the internet. Collections of such servers are called data centres, and they consume a phenomenal and increasing amount of energy. Worldwide, this amounts to about 30GW annually, approximately the same as the output of 50 nuclear power plants. The large data centres, which serve the computing ‘cloud’, consist of thousands of rows of servers spread over hundreds of thousands of square metres. Many organisations have smaller ones, down to single roomfuls of servers, servicing their own needs. Data centres probably have the most potential for reducing energy use of any industrial or commercial sector.
