Enhancing energy efficiency in buildings using phase-change materials, acrylic paint, and solar shading in hot climates

In 2023, total greenhouse gas (GHG) emissions around the globe increased to 41.6 billion metric tons of CO 2 equivalent. Most of this emissions increase came from the use of residential electricity. In this regard, this study introduces a new integrated approach to enhancing energy-efficient buildings. This is in the above-mentioned context as it explores promising passive cooling strategies for reducing energy consumption and emissions in hot climatic conditions of the Middle East regions. The analysis incorporates integrating phase-change material (PCMs) with the reflective coating and the shading by solar PV panels not fully considered in other studies. In contrast to the conventional usage of PCMs or reflective coatings alone, it is found that their combination provides for a far better thermal management system for the building for minimizing heat absorption while allowing greater heat redistribution. Using ANSYS FLUENT software, experiments of the designs, the cooling loads, and CO 2 emissions were validated through experiments conducted in earlier studies. The investigation shows that defining PCM integration and reflective coating individually reduces heat gain by 76.57 %,56.70 %, respectively; however, due to the greater microclimate efficiency of the building, these configurations do not yield the greatest heat gain reduction. Using PV panels as roof shaders show a 92.69 % heat gain reduction, and combining the reflective coating with PCM integration produced an 84.12 % reduction. Thus, it was found that the mass of CO 2 emissions was 5.767 kg, 3.797 kg, 0.671 kg, and 2.114 kg for the respective 4 days for the cases of reflective coating, PCM integration, PV-shading and of reflective coating and PCM combined, respectively. This gives a direct comparison of several roof systems under hot climates for the first time and will aid in sustainable building design and climate resilience engineering.