The ECOCASA Project (Intelligent spaces and social computing for behaviour change in end-consumers) aims at creating a novel platform to change the behavior of residential energy consumers towards more efficient habits that would lead to a drastic reduction in the consumption/production of energy and emissions, without crossing the consumers´ comfort levels. This platform will be designed as a social machine, where humans and computers collaborate, using energy data from meters, smart home devices and public data, as well as human interactions on the basis of data collected from social networks. As a result, we will obtain a new product that will be used on the market to stimulate users´ behavior through persuasive suggestions and collective challenges, leading to energy efficient habits, triggering measurable changes through personalized social strategies in combination with intelligent control and automation in smart homes and buildings.