Energy efficiency is presently a buzzword that has created new challenges and opportunities over several markets and industries.

Buildings consumptions are known to be responsible for over 30% of the overall energy consumption in the world. Reducing facilities consumptions has been recently considered as a main priority no just because of the referred weight but also due to its optimization potential. In fact, unexpected collaborations like IBM and Cisco have recently been done just to deal with this subject and Google has its own task force.

In this talk it is firstly presented the way how consumptions are generically managed in facilities. Some techniques like data warehouse analysis, data-mining or machine learning are then considered to be used as tools to classify and quantify consumptions and ultimately define feedback strategies to buildings behavior.