Assessment of annual performance of quonset GiPVT system combined with an earth-air heat exchanger (EAHE) for hot and dry climatic conditions

Abstract

Annual performance of a Quonset-shaped GiPVT system combined with an earth air heat exchanger (EAHE) has been evaluated for hot and dry climatic conditions. A periodic thermal model for the GiPVT system has been developed in terms of input climatic and design parameters by employing the energy balance equations of the greenhouse system. The present model is used to calculate the effective cooling and heating capacity of the EAHE, which is further utilized to determine the optimum operating hours of EAHE for different months of the year. Furthermore, the electrical energy of the GiPVT system and the thermal energy of EAHE are calculated, enabling a comprehensive performance evaluation of the greenhouse system. Results show that the EAHE increases the greenhouse air temperature by 8 °C on the coldest day and decreases the greenhouse air temperature by 21 °C on the hottest day of the year. EAHE has a lower potential for heating than cooling because of the hot and dry climatic conditions. Moreover, the system generates 17.6 kWh and 29.22 kWh of electrical energy on an extremely cold and hot day, respectively making the system self-sustainable. The EAHE significantly reduced TLL and DF values, which gives thermal comfort to the greenhouse.