Hydrogeological Assessment of the Groundwater Heat Pump (GWHP) System

Subject Areas : Water and Environment

Hajar Barzegar ¹ (Former M.Sc. Student of Hydrogeology, Shahrood University of Technology, Shahrood, Iran)
Hadi Jafari ² (Associate Professor of Hydrogeology, Shahrood University of Technology, Shahrood, Iran *(Corresponding Author))
Seyed Majid Hashemian ³ (Assistant Professor of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran)

Received: 2017-10-11 Accepted : 2018-10-10 Published : 2020-09-22

Keywords: MT3DMS, Groundwater Heat Pump, Heat simulation, GWHP,

Abstract :

Background and objective: Groundwater heat pump (GWHP) system that uses the constant temperature of the groundwater as the source of the clean and renewable energy for heating and cooling, is applied as a strategy for energy saving and the CO2 reduction. In this technique, groundwater is extracted by pumping wells, passed through the heat exchanger and then returned to aquifer through the injection shafts. This research is aimed to assess the Groundwater Heat Pump (GWHP) System from hydrogeological point of view.  Method: Regarding the mathematical similarities between transport of the heat and mass in porous media, the applied computer code of MT3DMS in mass transport modelling, was used in this study for simulation of the heat transfer in the groundwater system to assess the GWHP from hydrogeological viewpoint. Finding: The results show that a thermal plume is developed around the injection well due to the energy exchanges in GWHP system. This plume is regarded as an indicator of the impact of the injected water temperature on the underground source. Its extent and direction which are directly affected by the hydrogeological parameters is not fair from the heat transport aspect and finally the performance of the GWHP system.  Discussion and Conclusion: Modelling results clearly show that with the change in hydraulic conductivity in relation to the type of the sediments in porous media, hydraulic gradient and porosity of aquifer, the extent of the thermal plume is changed, expecting impacts on functionality of the GWHP system. The results of the study can be used in utilization of the GWHP system in the country, of course after the technical-and-economic justifications.

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