Urban Data-Driven Energy Planning: Insights and Challenges from Italy and Portugal

Effective urban planning for sustainable and equitable development requires data-driven support for policymakers to enable context-specific actions. Big and Open Data can serve as valuable resources for technicians and policymakers, transforming scientific knowledge into decision-support tools. However, the complexity and lack of standardisation of such data can create significant gaps. In the energy sector, open data issues are even more complex due to multiple stakeholders, privacy concerns, and varying motivations for collecting energy consumption data, such as municipal taxation versus energy management. This paper investigates these critical issues, which underpin the development of reliable, data-driven methodologies for understanding urban systems and supporting targeted interventions. Through two comparative case studies in Italy and Portugal, we highlight how data structure and accessibility shape the methodological approach and outcomes. In the Italian case study, conducted in Naples, comprehensive energy consumption data were available through the Siatel platform, including detailed records for individual users across the city. While the richness of the dataset enabled high-resolution analysis, the primary challenge lay in accurately geocoding and spatially integrating user-level data within the urban fabric. In contrast, the Portuguese case study relied on more aggregated energy datasets, where the key methodological challenge was disaggregating and translating large-scale information into finer spatial units suitable for meaningful urban analysis. The comparison demonstrates that even when adopting replicable methodologies and modelling approaches, valid cross-city comparison depends on explicit harmonization of the target variables produced from distinct data infrastructures, because addressing data-specific constraints is essential for producing effective, context-sensitive planning solutions.