A review of passive building thermal management with phase-change materials

The soaring global demand for renewable energy and building energy efficiency has significantly propelled the application of phase-change thermal storage walls in passive building thermal regulation and solar thermal energy harvesting. This study reviews innovative designs such as Trombe walls embedded with phase change materials, multilayer composite phase change walls, and solar photovoltaic-integrated phase change walls, revealing an average energy efficiency improvement of 15 %–20 % in thermal energy storage and release. Compared to building energy efficiency of traditional insulation materials, phase change materials can achieve energy savings ranging from 23.5 % to 52.7 %. Incorporating phase change materials into walls and ceilings not only enhances indoor comfort but also achieves a 42 % cost reduction and a 32 % decrease in energy consumption. A heating system combining solar air heaters with ventilated phase change wall exhibits heat storage efficiencies between 76.3 % and 87.6 %, and heat release efficiencies within the range of 75.2 %–83.2 %. The use of two layers of phase change walls, each with a thickness of 30 mm, can enhance energy efficiency by 6.4 % in summer and 17.8 % in winter. This study enhances thermal energy management by summarizing phase change materials selection, encapsulation techniques, and new material exploration. It overviews phase change wall applications across regions, showcasing energy self-sufficiency, especially in solar energy use. Precise simulations on heat transfer processes provide a basis for design optimization. Future research will focus on phase change materials performance optimization, energy technology integration, intelligent control, driving buildings towards greater energy self-sufficiency and environmental friendliness.