In the last years, the increasing social awareness about the need for containing energy consumption within sustainable rates has caught the interest of both the industrial and academic communities. In this scenario, Internet - and more generally ICT - may play a twofold role, being both a significant energy consumer and a potential actor in steering a more clever usage of energy resources. Both aspects of the problem raise interesting scientific challenges, and require a comprehensive effort and inter-disciplinary research at all levels of abstraction. The goal of this conference is to bring together people from different research areas, and provide a forum to exchange ideas, discuss solutions, and share experiences among researchers, professionals, and application developers both from industry and academia.