Integrating static insulation versus dynamic PCM materials in building walls for desert climate conditions: A comparative assessment.

This study investigates the thermal performance, energy savings, and indoor thermal comfort associated with integrating static thermal insulation and dynamic phase change materials (PCM), both individually and in combination, into building walls under extreme desert climate conditions. The objective was to identify the most effective wall configuration for minimizing heat transfer and energy demand while enhancing thermal comfort, taking into account the effect of varying the cooling setpoint. The analysis was conducted numerically using EnergyPlus through the DesignBuilder interface. The findings indicate that thermal insulation alone consistently outperformed PCM in terms of reducing both heat transfer and cooling energy use, irrespective of the cooling setpoint. Additionally, while raising the cooling setpoint in the reference case reduced energy demand, it increased thermal discomfort during summer. In contrast, the integration of thermal insulation and PCM maintained indoor conditions within acceptable comfort thresholds. Besides, the combined application yielded further performance improvements, achieving up to 82.5 % reduction in heat transfer, 45.4 % energy savings, and enhanced thermal comfort. However, the additional benefits of combining PCM with insulation, amounting to only about 5.1 percentage points more energy savings compared to insulation alone, should be carefully balanced against the higher installation costs, which may not always be economically justified.