A study on dedicated outdoor air handling unit systems regarding the widespread of ZEB

• Published in: E3S web of conferences 2023-01, Vol.396, p.3012
• Main Authors: Suzuki, Shogo, Yoon, Gyuyoung
• Format: Article
• Language: English
• ISSN: 2267-1242; 2267-1242
• DOI: 10.1051/e3sconf/202339603012

ZEB has been promoted in the building sector to realize energy conservation and carbon neutrality. This has caused changes such as a decrease in the room sensible heat load factor and an increase in the outdoor air load ratio. In this study, the systems with a dedicated outdoor air handling unit (OAHU) are evaluated as air conditioning systems that can flexibly respond to a changing heat load, and guidelines for rational design and operation are given. A case study is conducted to evaluate the indoor environment and energy performance of a conventional air handling unit (AHU) system and an OAHU system under the assumption of a reduction in internal heat gain intensity. The study results showed that the OAHU processed latent heat and reduced the number of uncomfortable hours by 78% compared to those for the AHU system during the cooling season for cases with reduced internal heat gain. Regarding system energy consumption, the OAHU system consumed 17% more energy than the AHU-system. Thus, the OAHU system maintained a better indoor environment than the AHU system at the cost of increased energy use. Based on these results, measures for reducing the energy consumption of the OAHU system are discussed.