Phase change materials for flexible refrigerated warehouses: a multi-level review of material properties, system integration, and control strategies

With the rapid expansion of refrigerated warehouses (RWs) to meet growing demands for food safety and cold chain logistics, the resulting substantial energy consumption and operation costs have become critical challenges for development. However, current knowledge on the integration of PCMs into RW systems lacks a comprehensive review, leading to gaps in understanding their thermophysical suitability, specific integration configurations, and control coordination mechanisms. This review, consequently, presents a timely and structured multi-level analysis of recent progress in the application of phase change materials (PCMs) to achieve flexible RWs, incorporating the aspects of material properties, system integration, and control strategies. The cutting-edge contributions of this review lie in its holistic perspective, which bridges: (1) the material science view of PCM thermophysical properties and heat transfer enhancement; (2) the thermal engineering perspective of multi-zone load characteristics and refrigeration system advancements in RWs; and (3) the systems control perspective of PCM integration and intelligent control. Persistent challenges such as PCM-refrigeration compatibility, long-term reliability, and demand response implementation highlight the need for future research to advance intelligent, resilient, and grid-interactive refrigerated warehouses, thereby establishing a robust foundation for the sustainable transformation of the cold chain sector.