Blockchain for digital twins to empower smart city

Rapid global urbanisation is driving the need for a smart city capable of providing more efficient and responsive municipal administration. To realise the full potential of a smart city, it is essential to adopt emerging technologies that are people-centred and foster high-tech innovations. This chapter explores the integration of two transformative technologies: Digital twins (DT) and blockchain, both of which hold the potential to revolutionise smart city development. DT technologies enable real-time virtual simulations, which aid in result prediction, situational control and link to metaverse applications. These simulations create a dynamic, data-driven urban infrastructure that enhances decision-making and operational efficiency. Blockchain technology, on the other hand, contributes to the development of smart cities by improving traceability, transparency and connectivity while establishing a secure, decentralised framework for efficient service management. By ensuring data integrity, blockchain empowers secure and transparent interactions across urban services, helping smart cities offer convenient and secure services to citizens. This chapter investigates how these two technologies can be integrated into a comprehensive smart city model. It begins by explaining the concepts of DT and blockchain, followed by a detailed analysis of their roles in enhancing urban management, resource optimisation and citizen engagement. Through real-world case studies - including applications in transportation, energy management and environmental monitoring - the chapter demonstrates how blockchain-enabled DT systems have been successfully deployed to optimise city operations. Additionally, the chapter delves into the challenges associated with this integration such as scalability, data interoperability and privacy concerns. By addressing these challenges, this research offers insights into building sustainable, resilient and citizen-centric cities of the future. In conclusion, the chapter emphasises the transformative potential of integrating blockchain and DT in smart city development, providing a roadmap towards secure, efficient and sustainable urban ecosystems.