Performance of energy piles foundation in hot-dominated climate: A case study in Dubai

Energy piles represent an innovative technology that can help provide sustainable geothermal heating or cooling energy for thermal conditioning purposes. In hot-dominated climates, the interest is to inject heat in the ground and extract energy for space-cooling purposes. This study evaluates the feasibility of energy piles in these regions through three-dimensional numerical modelling. The modelling framework is validated against a published experiment and is able to sufficiently capture the development of outlet temperature over time. The numerical analysis is then used to evaluate a case study in Dubai where it is targeted to provide 40 % of the cooling demand of a typical building. The unbalanced energy demand causes an increase in the outlet temperature of the heat carrier fluid and the radial temperature over time. However, observation of long-term behaviour indicates that the temperature increase is most significant in the initial years and gradually stabilizes over time. This stabilization enables to respect the outlet temperature limitation of the heat pump over 50 years. A sensitivity analysis confirms these observations with respect to system dimensioning variables. The obtained results highlight the effectiveness of energy piles to decarbonize energy supply in buildings in hot-dominated climates via the use of renewable energy sources.