Energy saving performance of dual-mode adaptive wall with phase change material and dynamic louver

Passive solar design is essential for developing energy-efficient buildings. Traditional passive solar walls often struggle to regulate solar heat gain effectively under varying climatic conditions. This study proposes a novel Thermal Diode Solar Wall (TDSW) integrated with translucent phase change material and dynamic louver control, establishing a dual-mode thermal regulation mechanism. The TDSW mitigates summer overheating, provides winter heating and daylighting, and enhances thermal comfort and energy efficiency. The operational results from test and reference rooms across multiple climatic regions in China demonstrate the effectiveness of TDSW. In Kunming, the TDSW test room showed an 8.36 °C temperature difference in winter, while in Beijing, it reduced indoor temperatures by 6.36 °C in summer. The TDSW absorbed up to 1500 W of solar radiation in winter, with Tibet receiving up to 10.71 GJ annually. In Yunnan, the cooling load decreased by 2.59 GJ, and 55.14 % of annual solar radiation was blocked in Hainan. Comfort hours in Yunnan increased by 2429 h (114.71 % improvement). The test rooms achieved up to 6.67 GJ in annual energy savings, with an energy-saving rate of 87.58 %. The TDSW demonstrates substantial thermal benefits, enhancing thermal comfort and energy efficiency, positioning it as an optimal solution for sustainable building design.