Abstract
The smart energy city is an emerging concept in urban development, aiming to optimize urban energy systems and improve the quality of life for citizens. However, smart energy city development requires a well-defined and consistent conceptual core in order to ensure its accurate interpretation and successful implementation. This research aims to define smart energy city development not only in a theoretical context, but also in terms of practical solutions. We adopt the 5W + 1H (why, what, who, where, when, how) model integrated with literature review and expert knowledge elicitation, i.e., focus groups and interviews. This results in: (i) clarification of general interrelationship between smart energy city, smart city, and sustainable city; (ii) a holistic, multidisciplinary, and comprehensive conceptual framework of smart energy city, revealing its principles, objectives, domains of intervention, stakeholders, and time and spatial scales; and (iii) a set of smart energy practical solutions and technologies categorized in the eight domains of intervention: buildings and districts, transportation and mobility, energy and ICT (information and communication technology) infrastructures, collaborative planning, consumer behavior management, energy and data management, as well as two cross-cutting domains. We suggest that sustainable, rational, and integrated application of new technologies, collaboration of multiple stakeholders, and integration of multiple urban energy domains, mainstreamed in energy specific targets, enable distinguishing real from labeled smart energy city development. We suggest that smart energy solutions are mostly effective when combined with other sustainable solutions. This research is applicable for all smart energy city stakeholders, particularly decision makers and researchers, in order to enhance a common and comprehensive understanding of the smart energy city concept and its practical solutions to foster sustainable smart energy city development.