Moving towards an energy efficient future: essays on energy efficiency, technology and development

Energy efficiency is a key element in the pursuit of sustainable development. This dissertation provides a comprehensive narrative of how energy efficiency and the technologies related to energy efficiency evolve over time. The results show energy consumption increases caused by development can be roughly offset by reducing the energy intensity and lowering energy intensity within sectors is the overwhelming factor behind the decline in aggregate energy intensity. Based on a statistical approach on big data of individual vehicles and their owners in Massachusetts, the importance of reallocation of new vehicles for the growth of aggregate vehicle energy efficiency and the convergence of aggregate vehicle energy efficiency between municipalities, is confirmed. Using big data on patents the results show that latecomer countries tend to contribute less to the main technological trajectories related to energy efficiency. The optimal path method using patent citation networks may inspire studies in any other technological fields, and enable policymakers and investors to monitor technological development and discover business opportunities