Multi-objective optimal design of a solar absorption cooling and heating system under life-cycle uncertainties

SACH systems, as a type of renewable energy systems, meet building cooling and heating demand through solar energy and therefore can reduce energy consumption and, in turn, mitigate the environmental impacts associated with building operation. Many researchers have evaluated and optimized the design of SACH systems under deterministic schemes; however, deterministic approach is subject to uncertain parameters in the evaluation or objective functions such as energy prices in the future and the results subsequently may not hold true. To enhance the design robustness and validate the use of deterministic approaches, a stochastic multi-objective optimization (SMOO) model is developed that incorporates these uncertainties. In this paper, a SACH system is optimized with respects to life-cycle energy, economic, and environment performance. The uncertain parameters considered include the life span of SACH systems and the fluctuations of energy markets and financial conditions. A case study follows to investigate the relationship among uncertainty and different designs. The comparison between deterministic and stochastic optimization shows that deterministic optimization can be used by designers who are moderate or not risk-averse at all.