Utilization of Soil Temperature Modeling to Check the Possibility of Earth-Air Heat Exchanger for Agricultural Building

Document Type: Original Article

Authors

1 Department of Biosystems Engineering, College of Aburaihan, University of Tehran, Tehran, Iran

2 Agricultural Engineering Research Institute (AERI), Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran

3 Department of Agricultural & Biological Engineering, Purdue University, West Lafayette, USA

Abstract

The commonly used energy in Iranian greenhouses is provided from gas or diesel fuel. As fossil fuels will be finished in the coming years, the utilization of renewable energies could be quite significant. In this research, the thermal potential of the soil profile was studied in Kouhsar, Alborz province, Iran, for utilizing the shallow geothermal energy in order to supply thermal demands of building like greenhouses. Therefore, the temperature sensors were set at the four depths of 30, 100, 200, and 300 cm as well as at the ground surface. The results showed that the greater the depth, the less fluctuation of the soil temperature as well as the greater the temperature difference of the soil profile against the ambient air temperature. These results suggest that the potential of the earth could be used to warm up or cool down in this location for an agricultural structure like greenhouse. The soil profile temperature behavior was modeled at different depths by two methods as heat transfer and empirical. The empirical model was simpler than the other one. As the possibility of using geothermal energy in this region has not been investigated. This research could be an effective step for using renewable energy for agricultural structures like greenhouses.

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