JAUE2022-071: Evaluation of PV/T as an Auxiliary Heat Source for Enhancing Natural Ventilation at Office Buildings: A Case Study

Abstract

Over one-third of China’s total energy usage can be attributed to buildings, of which one-fifth is consumed within public buildings. Natural ventilation is an energy-efficient way to reduce building energy consumption and improve indoor thermal comfort. However, natural ventilation is still facing the problems of instability and insufficient air exchange. Stack ventilation system with auxiliary heat source of solar energy is an alternative way to improve the ventilation rate. In this research, a strategy of using the released heat of photovoltaic-thermal collectors (PV/T) system to enhance stack ventilation was proposed. The ventilation efficiency of the system was evaluated by using TRNSYS and Fluent. The results show that the average electrical efficiency of the PV/T unit is 18% higher than that of the PV unit, the annual heat and electricity generation per unit area of the PV/T are 197.7 kW‧h /year and 156.8 kW‧h /year, respectively. The ventilation rate of the ventilation chimney in the case with auxiliary heating of the PV/T is 7 times than that of the case without auxiliary heating. The proposed method will contribute towards to reduce energy consumption and increase the efficiency of natural ventilation in public buildings.