Building-integrated Solar Collector (BISC)

Abstract

The present study intends to develop building-integrated solar collector (BISC). The storage tank inside is designed in multi-function. BISC combines the solar collector and the water storage tank together with one face acting as the solar absorber. A double-glazing design is adopted to reduce the heat loss. A PC-based automatic operating system is designed and built to monitor the long-term performance of the BISC system with 8 collector units. Hot water discharge is controlled from 18:00 until 22:00 to simulate the hot water load of a family. The discharge rate is at 60 L/hr. A 30 L backup electric water heater was connected to the BISC system. The long-term test results in winter season show that about 50 % energy saving was achieved in clear days. The monitored results have also shown that the daily-total solar irradiation on a 75 o tilted surface (the BISC installed angle) is higher than the horizontal surface, about 40-50 % higher at Ht > 10 MJ/m^2day. This assures that BISC will produce more hot water in winter. This proves that the use of BISC as parapet or sun-shading canopy of a building (installation angle > 75 o) is technically feasible. The characteristic efficiency of the installed BISC with different colors is 0.34-0.39.