Thermal Performance and Energy Benefits of Dynamic Insulation-PCM Wall Systems Applied to Residential Buildings

Abstract This study uses a validated Resistance Capacitance (RC) Network modeling framework for analyzing the energy efficiency benefits of integrating dynamic insulation systems (DIS) with phase change materials (PCMs) in building energy simulations. DIS offers variable thermal resistance capability, while PCM provides enhanced energy storage capacity for building envelope systems. Specifically, four wall constructions, including only static insulation, only DIS, PCM with static insulation (i.e., PCM), and PCM with dynamic insulation (i.e., PCM-DIS), are considered. The analysis results indicate that coupling DIS with PCM in wall assemblies (i.e., PCM-DIS) can achieve significant reductions in the annual heating and cooling energy needs reaching 42.7% in San Francisco, CA, 29.2% in Golden, CO, 12.6% in Phoenix, AZ, and 41.6% in Minneapolis, MN, relative to statically insulated residential buildings. Sensitivity analyses show that lower PCM fusion temperatures consistently produced the greatest annual HVAC reductions across all climates, while higher switching ratios amplify the benefits of the PCM-DIS configuration. Although increased internal loads and building orientation reduced their relative savings, PCM-DIS configurations still maintained meaningful reductions in total HVAC use, demonstrating robust performance even under less favorable operating conditions.