Analysis of Strategies for the Optimization and Maintenance of the Geothermal Potential Resources in a Spa Hotel

The efforts to establish sustainable solutions that meet the increasing global energy demand have been continuously fostered. A promising approach that has been popularized is the utilization of geothermal potential, which can be exploited in several ways depending on the available enthalpy, from power generation to heating, ventilation, and air-conditioning (HVAC) operations. As the HVAC applications require a low enthalpy, they represent over 70% of the geothermal resources’ exploitation worldwide. Despite the great potential of such solution, if not properly maintained, it might deteriorate in the long term. As a result, it is fundamental to balance the heat in the ground, and to do that, it is important to use the ground as hot and cold source. This work aims to establish and analyse possible strategies to optimize and maintain the geothermal potential resources while exploiting them for the pool heating, domestic hot water, and thermal comfort of a spa hotel. For that purpose, a geothermal borehole logging of the soil where the borehole for geothermal exploitation is located was conducted to provide a better comprehension of the thermal behaviour of the ground. Then, to avoid ground thermal drift, heating and cooling operations of a geothermal heat pump were simulated along their respective performance, and the heat fluxes in the soil for both operations were analysed. Additionally, an air-source heat pump (ASHP) and a borehole with a depth of 250 m, which are also part of the proposed strategy, were simulated as well. The conducted simulations revealed a great potential to maintain thermal balance within the ground while obtaining a high performance for both GSHP and ASHP under the most severe circumstances.