Semi-Transparent Photovoltaic Thermal Greenhouse System Combined With Earth Air Heat Exchanger for Hot Climatic Condition

Abstract

Semi-transparent photovoltaic thermal (SPVT) greenhouse system combined with an earth air heat exchanger (EAHE) has been developed to make the system sustainable. The system is designed to cultivate plants in a hot climatic condition, where green net is provided, which bifurcates the enclosed space of the greenhouse into zone-1 and zone-2, and this green net cut the solar radiation incident on the plants. The influence of air changes in zone-1, mass flowrate of air flowing through EAHE, and packing factor on photovoltaic (PV) cell, air of the greenhouse, and the plant temperatures is investigated for a typical harsh summer day by using periodic model of these parameters. Furthermore, for a holistic performance assessment of this SPVT greenhouse, exergy, thermal load leveling, and decrement factor are evaluated. Results indicate that the optimum temperature range for plant growth (30 °C–37 °C) within the greenhouse can be achieved through a combination of ventilation in zone-1 and integration of EAHE. The temperature of plants reduced by 9 °C for 30 air changes in zone-1, and the temperature reduces further by 24 °C when EAHE having a flowrate of 0.5 kg/s is operated. The SPVT greenhouse system also generates 128 kWh of daily overall exergy that makes the system sustainable.