Refining the design approach for GeoExchange system

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In Alberta, new buildings have also been increasingly utilizing the GeoExchange system, which uses theshallow ground-mostly less than 150 meter-as an energy reservoir for space cooling and heating. In the system,the borehole heat exchanger (BHE) is the most crucial one because the efficiency of the GeoExchange systemrelies primarily on the thermal interactions between BHE and its surrounding ground. Currently, the designapproach of BHE is to use analytical solutions of heat conduction governing equations under the Laplacetransform. However, these models do not consider the impact of groundwater flow on the thermal performanceof BHE. This impact is beneficial because the advection of groundwater helps the dissipation of heat in theground and therefore provides a synergistic effect on the performance of BHE under both cooling and heatingmodes. Consequently, this design length of BHE can be shortened, and the drilling and installation costs can bereduced substantially. To this end, we propose research collaboration between Revolve Engineering Inc. andthe University of Alberta to conduct finite element method (FEM) modeling of the BHE by incorporating theco-simulation of groundwater. As a result, a more explicit understanding will be achieved on the complexthermal behavior of BHE, and the current analytical design approach will be refined for the GeoExchangesystem, leading to more economically feasible design. Since the GeoExchange system is increasingly popularacross Canada, the outcome of this research can be directly used in other nationwide projects.