Energy saving potential of fresh air pre-handling system using shallow geothermal energy

To reduce the energy consumption for fresh air handling, a novel fresh air pre-handling system that fully exploits the shallow energy to precool and preheat fresh air is proposed in this study. The model of a typical all-air system with a pre-handling system is built on the TRNSYS platform. The energy saving potential of this fresh air pre-handling system is simulated based on the diverse climate of China. The results show that the ratios of the cumulated heat transfer capacity of the fresh air pre-handling system to the annual total of cooling and heating load range from 35% to 45% in the temperate zone and the subtropical zone, such as Shenyang, Beijing, and Shanghai, while the ratio in the tropical zone is approximately 10%. The energy saving rates are approximately 30% in most climate zones, but less than 5% in Guangzhou, the tropical climate zone. Moreover, the payback periods are within 4 years in the temperate and subtropical zones. However, the system is not economical in the tropical zone. All these results indicate that the fresh air pre-handling system with shallow geothermal energy is quite promising in most climate zones except in the hot summer and warm winter region with a tropical climate. (C) 2019 Elsevier B.V. All rights reserved.