Efficiency and Applications of Nanocomposite Materials in Thermal Energy Saving

Nanocomposite materials have gained significant attention as advanced solutions for thermal energy saving due to their ability to enhance heat transfer, improve insulation, and store thermal energy more efficiently. This study presents a systematic classification and comparative analysis of six categories of nanocomposites—including nanofluids, thermoelectric composites, polymer-based systems, carbon-based materials, phase change materials (PCMs), and building insulation nanocomposites. Performance parameters such as convective heat transfer coefficient (HTC) and thermal transmittance (U-value) were benchmarked and visualised using data extracted from peer-reviewed sources. Results indicate that graphene- enhanced nanofluids achieve up to a 60% improvement in HTC, reaching 160 W/m²·K, while aerogel-based insulation materials reduce U-value by 50%, down to 0.6 W/m²·K. These findings confirm the potential of nanocomposites to significantly improve energy efficiency in applications such as solar thermal systems, HVAC, waste heat recovery, and passive buildings. Nevertheless, challenges such as nanoparticle agglomeration, interface thermal resistance, and cost constraints remain. This work provides a comprehensive overview of nanocomposite capabilities and highlights future directions for their integration into sustainable thermal management technologies.