At temperatures below 60?C, the best way to use geothermal sources for
heating is to use heat pumps. A heat pump can provide air conditioning for a
residential, commercial, etc., all year round by heating in winter and
cooling in summer using a low-temperature source. Also, a heat pump can be
used for water distillation through evaporation. The ground source heat pump
with a high COP and low-temperature thermal energy sources is one of the
best technologies for using renewable energy sources. In the present study,
the effects of changing ambient temperature and soil temperature on a heat
pump's overall COP and energy efficiency are investigated using a simulated
geothermal heat pump with an economizer. The system's thermodynamic
simulation is first performed in the EES software for R134a and R513A
working fluids. The exergy destruction of different components for both
working fluids was calculated and displayed as a figure. COP of the heat
pump for R134a working fluid is equal to 3.916, equal to 3.729 for R513A
working fluid, which indicates that R134a fluid has about 5% better
performance. COP of the system for R134a working fluid is equal to 3.662,
which is equal to 3.504 for R513A working fluid, which indicates that R134a
fluid has about 4.5% better performance.