Performance evaluation of a novel building envelope integrated with thermoelectric cooler and radiative sky cooler

Abstract

Heat loss or heat gain through building envelopes accounts for a large part of heating or cooling loads. The development of high-performance building envelopes is the key towards building energy efficiency. In this study, a novel building envelope integrated with thermoelectric cooler and radiative sky cooler (TEC-RSC) was proposed, not only for the elimination of heat gain through itself but also for space cooling. Considering the mismatched heat flux generated by radiative sky cooler and that by thermoelectric cooler, the spacing of thermoelectric elements in TEC-RSC was redesigned. To evaluate the performance of TEC-RSC, a global sensitivity analysis was conducted based on the TEC-RSC model. Four key parameters including direct current, area enlargement coefficient, thermoelectric element height and cross-sectional area were identified and their combined effects on TEC-RSC were analyzed. Through optimization design, the TEC-RSC can provide a cooling capacity of 25.49 W/m2 with a COP of 2.00 under the condition of global solar radiation of 1000 W/m2, ambient temperature of 35 °C and outdoor relative humidity of 60%. Further study shows that it can provide a cooling capacity of 35.05 W/m2 with an averaged COP of 3.01 in typical hot climate regions.