Abstract: A novel system of dual-functional building integrated solar collector is proposed. The system can run in two independent modes: passive space heating in cold days and solar water heating in hot days. Dynamic numerical models have been established to investigate the performance of the system in the two operating modes. Results show that when the system works in the space heating mode, the indoor air temperature reaches the maximum value of 274 ℃, with the maximum value of ambient temperature being only 28 ℃; when working in the water heating mode under given simulation conditions, the thermal efficiency of the collector is 548%, with the solar heat gains being 432 MJ/m2.

Key words: dual-functional solar collector integrated with buildings, passive space heating, water heating, thermal efficiency