Green IT - available data and guidelines for reducing energy consumption in IT Systems

Nowadays saving energy is an interdisciplinary key challenge. Green IT deals with saving energy in IT systems, and is rapidly gaining momentum. Hardware manufacturers and designers have first considered the problem, in the field of IT, but recently software energy efficiency gathered the interest of industry and academic research. In this paper we aim at summarizing the available knowledge in Green IT. In particular we: • Introduce a taxonomy of concepts related to energy and IT. • Present recent data on energy consumption trends organized according to the taxonomy. • Present some guidelines to write energy efficient software organized according to the taxonomy. • Underline what is missing and what should be done in future research.