Effectiveness of a thermal labyrinth ventilation system using geothermal energy: A case study of an educational facility in South Korea

Ventilation is essential to maintaining a healthy indoor environment. However, during the summer and winter seasons, the temperature of the outdoor air can be so extreme that providing adequate ventilation requires a significant amount of energy. Consequently, an energy-efficient ventilation system is important for minimizing energy consumption. The thermal labyrinth is a ventilation system that pulls in outdoor air through an underground labyrinth-shaped concrete structure that is part of the building itself. Through heat exchange with the ground, this system can pre-cool and pre-heat the outdoor air in the summer and winter seasons, respectively. The goal of this study was to evaluate the energy performance of the thermal labyrinth ventilation system (TLVS) used in the Ewha Campus Center building recently built in Seoul, South Korea. By using the TLVS, the peak loads for the cooling and dehumidification and the heating and humidification of the outdoor air were found to be reduced by 47.6% and 41.2%, respectively. The annual energy need for conditioning outdoor air was reduced by 31.3%, and a payback period of 12.1 years was calculated.