Comparing Smart Cities Concepts

Urban areas cause 70% of global CO
₂
-emissions already today. This share is continuously growing, mainly due to a general urbanization trend. This makes cities one of the major addressees with regards to CO
₂
reduction policies. A potential framework to deal with the challenges of radically reducing energy demand while grounding it mainly on renewable energy sources is the smart energy city (SEC) concept. This work provides an overview of the SEC concept by comparing three SEC models regarding their central characteristics and synthesizing them into a common approach. This comparison finds that all three models regard infrastructure, buildings, and transport as the main areas of intervention, such as upgrading the legacy grid into a smart grid or substituting vehicle fuels. Extending these findings, a unified smart energy city model (USECM) is proposed, which can serve for decision-makers as a basis for the conceptualization of SEC initiatives and directing their attention to critical aspects of SEC development.