Multi-objective optimization and thermal performance evaluation of a novel Trombe wall

To minimize buildings' energy demand for space heating/cooling and water heating while maximizing solar energy utilization, this study proposing a multi-mode operating Trombe Wall (TW). Employing the orthogonal experimental and entropy weight method, this study introduced a novel multi-objective optimization approach, complemented by a mathematical expression to evaluate the TW's performance. The influence of four key parameters on the TW's performance across multiple objectives were investigated. Results show that the thermal efficiency of the novel TW can reach 78.54%. The total heat gain of the proposed TW can reach to 384,639 kJ during a typical day in Beijing winter, with 16.01 kJ conventional energy substitution quantity, 39.53 kg CO₂ emission reduction, 0.32 kg SO₂ emission reduction, and 31.27 Yuan cost saving. Significance order and optimal parameter combinations for six performance objectives were obtained, then an output performance (OP) evaluation index was proposed by entropy weight method. Scoring and ranking of the 16 schemes reveal that the highest OP score was the scheme with a water inlet temperature of 283 K, water flow rate of 0.07 kg/s, initial indoor temperature of 287 K, and a concentration ratio of 4.