Sensitivity analysis and optimization of PCM integrated buildings in a tropical savanna climate

Abstract

Several researchers have reported the importance of early design stage decisions in the building design process. Integrating phase change material (PCM) in buildings is a feasible method for enhancing energy efficiency. However, the following issues have not been addressed yet. (a) What is the most effective combination of early design stage parameters that minimizes the energy consumption of PCM integrated residential buildings? (b) Can the various sensitivity analysis methods generate a similar ranking of early design stage parameters? (c) Can the same set of early design stage parameters be used for tropical savanna climates? (d) Are the optimal solutions economically and environmentally feasible? Hence, this research proposes a multi-stage sensitivity and optimization of the PCM incorporated buildings in tropical savanna climates by considering building layout, envelope thermal characteristics, and energy efficiency measures. For multi-stage sensitivity analysis, at the first stage, global sensitivity methods (Morris, standard rank regression coefficients, partial rank correlation coefficients) were used followed by the utilization of the local sensitivity method. An evolutionary algorithm was used to optimize the key early design stage parameters. Finally, the economic and environmental analysis was performed on optimal solutions. Results showed that all methods generated a different ranking of the importance of early design stage parameters. Due to optimization, the annual energy use decreased by about 18.2–42.7% in comparison to the base case. In addition, the optimal solutions are economically and environmentally pronounced. It is concluded that early design stage parameter selection is crucial in reducing building energy consumption.