What factors will shape the future of sustainable and smart cities in Europe? Evidence from the Delphi study

The article aims to identify and assess the factors shaping the development of sustainable and smart cities in Europe and their interrelationships. With respect to the objective, three research questions were formulated: (I) What are the factors supporting the development of sustainable and smart cities in Europe?, (II) What are the limiting factors (barriers) to the development of sustainable and smart cities in Europe?, (III) What are the main factors influencing the development of sustainable and smart cities in Europe? As part of the research process, the following methods were applied: horizon scanning, STEEPVL analysis, the Delphi method and structural analysis. The study involved 131 experts from 28 countries, whose articles on sustainable and smart cities development are indexed in the Web of Science database. The directions analysed include: smart governance and citizen participation; renewable energy microgrids with decentralised energy trading; delegating decisions to AI-based systems; and urban digital twins. The Delphi results unambiguously indicate three main enabling factors: access to external sources of finance; advanced digital infrastructure together with data integration; and a high level of cybersecurity and data protection. The principal barriers were identified as: a low level of integration across urban systems and a lack of data interoperability; limited fiscal capacity of local authorities; and institutional resistance to change and to the digital climate transition. The results of the structural analysis indicate that institutional governance, the maturity of data infrastructure and interoperability set the trajectory of change. The findings entail practical implications: institutional governance and regulatory transparency should be strengthened; diversified, multi-source funding should be ensured; interoperability should be prioritised; and AI and digital twins should then be scaled in step with capability development and a security-by-design approach.