Underground thermal energy storage and exergy analysis for vertical loop ground source heat pump systems

Thermal energy storage (TES) is basically the temporary ?holding? of energy for later use.There are mainly two types of Thermal Energy Storage (TES) systems, sensible (e.g.underground thermal energy storage-UTES) and latent heat (e.g. phase change materials-PCMs). Underground Thermal Energy Stroage (UTES) systems under the definition of thisstudy can be divided into three groups:? Aquifer Thermal Energy Storage (ATES)? Borehole Thermal Energy Storage (BTES)? Cavity Thermal Energy Storage (CTES)In this study, a borehole thermal energy storage with heat pump is designed four differentrefrigerants make use of for a residence which is located in İstanbul. The system can carry outheating and cooling simultaneously. Firstly, the heat insulation, heat loss and heat gaincalculations are carried out, the ground heat exchganher?s lengths are determined. Afterward,the mass, energy, entropy and exergy balance relations are derived and applied to a BTESsystem with a heat pump. The performance characteristics of this system are evaluatedin terms of energetic and exergetic aspects.As a result of the analyis the objective is, to identify available energy loses in the componentsand also make use of refrigerants of the losses in the system.