As sensor networks in buildings continue to grow in number
and heterogeneity, occupants can become empowered to
better control their environment for comfort maximization
and energy minimization. Since buildings are the primary
consumers of energy and are the dominant cause of
greenhouse gases, apps that help occupants to understand and
control their interactions with a building could be extremely
beneficial to society. However, the massive raw data sets that
could be collected must be aggregated and visualized to be
usable which presents significant data handling, information
visualization, and interaction challenges. In the context of
Project Dasher, a prototype building site for exploring these
issues, we discuss lessons learned and challenges ahead to
develop ubiquitous computing support for sustainability.