Phase change material integrated roofs for minimizing heat transfer: performance and enviro-economic assessment

Phase change materials (PCMs) have shown strong potential for enhancing thermal comfort and reducing cooling loads in buildings. The experimental investigation was conducted on a test building situated in Chennai, India, a region characterized by hot and humid climatic conditions. Experimental results indicate that PCM-integrated roofs lower the inner surface temperatures by an average of 1.8 °C compared to conventional roofs. A validated numerical model, with a maximum relative error of 10.83% and an average error of 6.32%, was developed to assess performance. Two PCMs, HS29 and OM29, paired with steel and aluminium panels, were evaluated for energy savings, carbon emission reductions, and payback periods. Results show that HS29 and OM29 can reduce annual energy costs by 1294.38 and 2872.89 INR, and carbon emissions by 204.23 and 453.28 kg/kWh, respectively. Payback periods range from 8.3 to 29.8 years, with OM29 showing longer periods due to higher costs. PCM technology supports green building initiatives by lowering environmental impact and promoting energy efficiency, contributing to sustainability in the construction sector.