This thesis investigate how energy efficient measures has spread throughout the data centers in Sweden. These questions are put up against a theoretical use of such concepts such as green IT, technological evolution, large technical systems and knowledge dissemination. These theories are used to answer the questions that are encountered during the study, such as how green IT is approached, how big of a role environmental thinking has had in the evolvement of these new technologies. The study has been conducted in a longitudinal manner, it is an observation of the phenomenon that is data centers over a longer period of time. 23 non structured interviews spanning over 27.5 hours of recorded material have been conducted alongside a study of archived material. An overview of what a data center represents is first presented and then a number of cases involving different companies is then presented to give examples of how different actors have managed their data centers. Through these examples it can be seen that working towards a more energy efficient market among data centers is something that has been going on for a long time and is gaining a lot of ground today. A lot of today’s focus is leaning towards how to use computer power as a method of becoming greener. A cyclical pattern of the large accumulation of computer power is also an important factor here were the large centralizations of computer power enables big actors to focus more on greening.