On-site study on a desiccant-based air-conditioning system integrated with shallow geothermal energy
Journal
Energy Conversion and Management
Journal Volume
347
Start Page
120540
ISSN
01968904
Date Issued
2026-01-01
Author(s)
Abstract
In subtropical climates, hot and humid air results in significant electricity consumption for air-conditioning in residential and commercial buildings. This study aims to develop a high-efficiency hybrid air-conditioning system specifically designed for such climates. The proposed system integrates shallow geothermal energy, a desiccant wheel, and a ground-source heat pump, and separates the treatment of ventilation loads and indoor sensible heat loads, with multiple operating modes defined based on outdoor air conditions. Ventilation loads are managed through three distinct modes, selected according to the outdoor air humidity ratio. 65 test scenarios under varying ambient conditions were examined, showing that most supply air conditions remained within the thermal comfort zone. Indoor sensible heat loads were handled by a fan coil unit using chilled water, shallow geothermal groundwater, or hot water, depending on outdoor air temperature. Field experiments under subtropical climate conditions indicated that the proposed system reduced energy consumption by 34.3 % in a hot and humid summer and 18.7 % in mild spring and autumn periods. Annual operation analysis revealed that shallow geothermal groundwater alone could satisfy indoor sensible heat loads for approximately 39.5 % of the year; however, due to persistently high humidity, the desiccant wheel was required for about 49.7 % of operational hours. Full-scale field testing successfully demonstrated the system’s feasibility under subtropical climate conditions. Economic analysis further indicated a discounted payback period of approximately 8 years.
Subjects
Desiccant dehumidification system
On-site test
Shallow geothermal energy
Year-round operation analysis
SDGs
Publisher
Elsevier Ltd
Type
journal article