Authors: Jun Wang
Abstract—This paper analyzes the ground thermal responses of borehole heat exchanger and of solar PV panels assisted borehole thermal energy storage systems, when subjected to constant rate of heat extraction or injection. The undisturbed underground temperature is assumed to be uniform. Seven types of earth material are analyzed using mean values of their thermal properties. Simple equations for Zone of Influence and average temperature change, convenient for quick engineering assessment, are derived. The results show that, among seven underground materials studied, dry sand and sand aquifer are the best for storage application of thermal energy; whereas igneous is the best for dissipative application of geothermal energy.
Keywords: dissipative type application; storage type application; Borehole Heat Exchanger (BHE); Borehole Thermal Energy Sstorage (BTES); Zone of Influence (ZOI)