Phase change materials for buildings’ thermal energy management: an overview

Globally, energy consumption in the building sector is continuously increasing due to increasing heating and cooling demands from various applications. Phase change materials (PCMs) have emerged as promising solutions for enhancing the thermal storage of building materials. This study presents an overview of phase change materials and their classifications, which are commonly utilized in building applications. It also highlights key associated challenges, such as thermal efficiency, safety risks, and economic considerations. Various approaches for incorporating PCMs in their liquid state, along with different methods to improve their thermophysical properties, are explored. Additionally, the importance of strategically positioning PCMs within building structures, which can lead to considerable reductions in annual energy consumption and improvements in thermal comfort, is discussed. This study emphasizes the critical importance of selecting and placing PCMs appropriately to achieve optimal thermal performance and energy savings while also identifying future research directions. The graphical abstract shows a bibliometric analysis of key research areas and emerging trends in PCM applications for buildings from 2018 to 2025. The conclusions of these review papers offer a clear overview of the developments since 2018. Moreover, future research directions are outlined to support more efficient use of PCMs in building walls.