Photovoltaic-integrated Double Façades and the Future of Energy-autonomous Buildings

As the global push for sustainable architecture intensifies, the integration of building-integrated photovoltaic systems and building-integrated photovoltaic and thermal energy systems into double façade designs presents a promising solution for reducing energy consumption and enhancing building performance. This study explores how these technologies contribute to thermal efficiency, primary energy savings, and overall building sustainability, using a residential module in the Mediterranean, as a case study. Through advanced computer simulations, different façade cavity depths were analysed to determine their impact on energy performance and indoor comfort. Findings confirm that building-integrated photovoltaic systems and building- integrated photovoltaic and thermal energy systems significantly improve energy efficiency, with the building-integrated photovoltaic and thermal energy system achieving the greatest reduction in heating and cooling demands. An 74 optimal cavity depth of 0.97 meters was identified as the most effective in balancing thermal comfort, energy savings, and functional space usability, reinforcing its potential for nearly zero-energy building applications. This research is particularly valuable for architects, engineers, urban planners, and policymakers seeking to implement innovative renewable energy solutions in residential construction. The study underscores the importance of integrating passive and active energy strategies to create self-sustaining, energy-efficient urban environments. Additionally, it highlights the need for policy incentives and design optimization to accelerate the adoption of building-integrated photovoltaic systems and building-integrated photovoltaic and thermal energy systems in new and existing buildings. Future research should explore how regional climate variations, material properties, and urban density influence system performance, ensuring their adaptability for widespread implementation.