RES4CITY is a 36-month project funded by the European Commission, initiated in October 2022. Its primary objective is to advance the development of sustainable renewables and fuel technologies within cities. This is achieved by collaborative efforts in designing innovative educational micro-programmes involving various stakeholders. The project also emphasizes the promotion of sustainability and circularity, bridging the knowledge and skills gaps essential for a successful energy transition. This deliverable, designated as D.2.2 RES4CITY multidisciplinary and multi sector lighthouses, is developed under task T2.2 Lighthouse case studies development of the RES4CITY project during M12 (September 2023). Task T2.2 builds upon the energy-related urban challenges identified in T2.1 Innovative sustainable strategies for carbon neutral smart cities. In essence, task T2.2 focuses on creating lighthouse case studies that address these identified challenges. To ensure a comprehensive and effective approach, task T2.2 collaborates closely with task T3.2, actively engaging the community of stakeholders. The culmination of these collaborative efforts results in the production of pre-feasibility analyses tailored to the specific urban context under consideration. The document comprises three chapters. The first chapter introduces task T2.2, which involved the development of ten lighthouse case studies by project partners, along with their corresponding HUBs. This chapter describes the approach to ensuring clarity and enhancing reader comprehension, thereby amplifying the impact and dissemination of these case studies. To achieve this, the case studies followed a predefined template designed with a structure like that of a scientific article. This structure encompasses not only an introductory section addressing the challenge under scrutiny and introducing the case study but also includes sections dedicated to presenting results, recommendations, and conclusions. In the second chapter, the ten lighthouse case studies are compiled and presented individually. This set of lighthouse case studies contributes to fulfilling the RES4CITY’s Milestone 11 Lighthouse available for case study education. Each case study is accompanied by an executive summary, which complements the existing Abstract and Graphical Abstract elements that are part of the case study structure. The objective of creating this executive summary is to provide an additional resource that can be examined independently of the complete case study. Its purpose is to facilitate an understanding of the subject matter and the case study itself while highlighting key results and conclusions. This approach enables the case studies to be used independently. Within the framework of this Deliverable, the executive summary serves as tool for readers to grasp the key points of each case study swiftly and concisely. This empowers readers to determine, based on their interests and requirements, whether they want to delve deeper into the individual case studies for more detailed analysis. In the third and concluding chapter, each lighthouse case study developed by the project partners is presented in a straightforward and concise manner. Furthermore, this chapter highlights key concluding remarques derived from each of the case studies. Lastly, it emphasizes the dual purposes for which these case studies were developed: as learning tools in the RES4CITY learning and upskilling programs and as multipliers for replication in other contexts. The Deliverable 2.2 was concluded and submitted in September 2023 by (UCOI) with the support of the partners listed in Table 1.