Comparative Thermal Performance of Advanced Insulation Materials and Hybrid Wall Systems in Cold-Climate Buildings
Improving building envelope performance is a critical strategy for reducing heating energy demand and enhancing indoor thermal comfort in cold climates. This study evaluates the thermal effectiveness of four advanced insulation materials—phase change materials (PCM), aerogel, vacuum insulated panels (VIP), and autoclaved aerated concrete (AAC)—through dynamic energy simulations. Using 24 years of hourly climate data, five wall configurations were analyzed, including an uninsulated reference case. The research focuses on annual heating demand, surface temperature stability, thermal time lag, and comfort hours to determine how different material properties contribute to energy efficiency and occupant comfort.
Methodological Framework and Simulation Approach
The investigation employed dynamic building energy modeling using EnergyPlus, incorporating long-term hourly climate data to ensure robust performance assessment. PCM behavior was simulated through an enthalpy–temperature phase change algorithm to accurately capture latent heat storage and release. Each wall assembly—reference, PCM, aerogel, VIP, and AAC—was evaluated under identical boundary conditions. Performance metrics included annual heating energy demand, wall surface temperature fluctuation, time lag, and the percentage of annual comfort hours, enabling a comprehensive comparison of conductive resistance and thermal storage capabilities.
Energy Demand Reduction Performance
Among the evaluated materials, VIP demonstrated the highest reduction in annual heating demand, achieving a 36.6% decrease relative to the uninsulated reference. Aerogel followed with a 29.5% reduction, while AAC and PCM achieved 24.1% and 21.4% reductions, respectively. The superior performance of VIP and aerogel is primarily attributed to their ultra-low thermal conductivity, which significantly minimizes heat transfer. These findings highlight the effectiveness of high-resistance insulation materials in substantially lowering heating loads in cold-climate buildings.
Thermal Inertia and Surface Temperature Stability
While VIP and aerogel excelled in minimizing conductive losses, PCM and AAC provided enhanced thermal inertia. PCM delayed heat transfer by approximately 150–180 minutes, and AAC achieved a delay of 90–120 minutes, contributing to improved night-time comfort and reduced temperature swings. In contrast, VIP and aerogel maintained nearly constant interior surface temperatures, with fluctuations below 3°C. This distinction underscores the complementary nature of high thermal mass materials and ultra-low conductivity insulation in managing both steady-state and transient thermal conditions.
Hybrid Wall Configurations and Passive Solar Integration
Hybrid configurations combining high-resistance and high-storage materials produced the most favorable outcomes. The VIP+PCM wall system reduced annual heating demand by 40.3% and achieved approximately 6,510 comfort hours, representing about 74% of the year. The integration of passive solar gains further enhanced PCM performance by approximately 12% during sunny winter periods, demonstrating the importance of solar-responsive design. AAC showed moderate improvement under solar exposure, whereas VIP performance remained largely unchanged, indicating limited interaction with solar heat gains due to its strong resistance properties.
Sensitivity Analysis and Practical Implications
Sensitivity analysis revealed that VIP performance is vulnerable to vacuum degradation, with an estimated 12% reduction in effectiveness under compromised conditions. AAC performance showed dependence on moisture content, affecting its thermal resistance. Conversely, aerogel and PCM demonstrated greater robustness under variable conditions. Overall, the findings emphasize the strategic integration of ultra-low conductivity materials and thermal storage components to optimize energy efficiency and comfort. Although economic and practical challenges persist, hybrid insulation systems offer a promising pathway toward significant heating energy reduction and resilient building envelope design in cold climates.
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