Building Stock Energy Modeling (BSEM) is a critical methodology in the pursuit of sustainable urban development and effective energy management. As urban areas expand, buildings account for a significant portion of global energy consumption and carbon emissions. To address these challenges, the European Union has implemented directives aimed at optimizing energy performance in buildings. One critical approach to achieving this goal is through Building Stock Energy Modeling (BSEM), which facilitates data-driven strategies for energy efficiency improvements. This research focuses on developing and evaluating the performance and accuracy of BSEM tools: AssessCity, and Felicity. The study leverages standardized datasets from the TIMEPAC and TABULA projects, which provide comprehensive data on building parameters such as occupancy, envelope characteristics, energy systems, and environmental conditions.