Albania has been a cradle of various civilizations throughout history, possessing a rich cultural heritage with many buildings across the region designated as historically valuable. Due to the significance of these buildings, the extent of permissible changes is limited. The primary challenge in retrofitting historic structures lies in balancing the preservation of historical values with the need for energy efficiency. Often, achieving one goal requires compromising the other. Additional challenges include the complexity of retrofit work and uncertain building characteristics. This study aims to enhance the energy performance of the Polytechnic University of Tirana while preserving its historical integrity. By performing detailed energy simulations with Design Builder software, the study assesses the effectiveness of different interventions. The results indicate that the implementation of photovoltaic (PV) panels constitutes the most effective intervention, yielding a substantial 49.10% energy saving compared to the baseline. Overall, sustainable interventions reduced energy consumption by an average of 20.18%, demonstrating that heritage buildings can be made sustainable without sacrificing their historical and cultural value. This study demonstrates the potential of technological advancements to support the development of resilient, energy-efficient heritage buildings. The findings provide a model for future sustainable conservation projects, showcasing how to balance historical preservation with energy efficiency. The results emphasize the value of targeted retrofitting in protecting cultural heritage while advancing sustainability objectives.