Tunnelling and Underground Space Technology

In response to rising energy demand and urban heat island effects in Taipei, an energy raft foundation was constructed beneath a 13-story residential building to provide energy-efficient indoor heating and cooling for the residents while acting as a structural support for the superstructure. This study investigated the thermal response of the energy raft foundation using three-dimensional coupled thermo-hydraulic finite element analysis. The numerical model was validated against field measurements. Parametric studies were conducted to investigate the influences of ground heat exchanger (GHE) spacing and pattern on heat exchange efficiency. The study found that GHE pipe spacing and length were crucial in maximizing heat exchange efficiency while minimizing the thermal impact on nearby structures. This research enhances the understanding of the thermal responses of energy rafts and supports the development of sustainable building solutions in dense urban environments.