Analysis of an earth‐to‐air heat exchanger for enhanced residential thermal comfort

Abstract

It is well known that a massive demand for thermal comfort has resulted in a sharp rise in energy use for residential space heating and cooling. This article presents numerical simulations of a room coupled with an earth‐to‐air heat exchanger system operating at the climatic condition of 21.2497° N, 81.6050° E for both summer and winter seasons. The present study involves an estimate of monthly variations in soil temperature at different depths and a suitable geometrical arrangement of pipe is proposed. The thermal performance of the earth‐to‐air heat exchanger system in terms of the outlet air temperature and effectiveness has been calculated. It is shown that with an effectiveness of 0.77 in summer and 0.78 in winter, the present EAHE system reduces the ambient air temperature from 38 to 28.2°C in the summer and it rises from 13 to 22.9°C in winter, respectively. Finally, an improvement in the thermal comfort condition of the room exposed to the solar radiation has been examined at different time intervals and different heights of the room. During the summer the room temperature dropped by 4.2°C while in winter it rose by 5.2°C. Furthermore, the environmental effects of system have been evaluated, showing energy savings of 3.90 kWh/day during summer and 4.83 kWh/day during winter leading to a decrease in CO2 emissions of 6.13 kg/day in summer and 7.59 kg/day in winter.