[ Environmental Engineering ]
Journal of Asian Architecture and Building Engineering - Vol. 11, No. 2, pp.407-414
ISSN: 1346-7581 (Print) 1347-2852 (Online)
Print publication date 30 Nov 2012
Received 05 Oct 2011 Accepted 24 Jul 2012

Reduction of Energy Consumption by AC due to Air Tightness and Ventilation Strategy in Residences in Hot and Humid Climates

Tomoko Uno*, 1 ; Shuichi Hokoi2 ; Sri Nastiti N. Ekasiwi3 ; Noor Hanita Abdul Majid4
1Lecturer, Department of Architecture, Mukogawa Women's University Japan
2Professor, Graduate School of Engineering, Kyoto University Japan
3Lecturer, Department of Architecture, Institute Technology Sepuluh Nopember Indonesia
4Associate Professor, Department of Architecture, International Islamic University Malaysia Malaysia

Correspondence to: *Tomoko Uno, Lecturer, Department of Architecture, Mukogawa Women's University, 1-13, Tozaki, Nishinomiya, Hyogo, 663-8121, Japan Tel: +81-798-67-4501 E-mail: uno_tomo@mukogawa-u.ac.jp


This paper proposes strategies for reducing energy consumption for cooling in residences in hot and humid climates. Based on the results of fieldwork measurements and questionnaire surveys, a simulation of indoor thermal environments in consideration of air conditioner operation was carried out, in order to evaluate energy consumption by air conditioners. This simulation program takes into account both heat and moisture transfer in building materials. In order to simplify the calculation and due to lack of measurement of ventilation volumes, the ventilation volumes are assumed as constant values depending on open or closed windows. The combined effects of building air-tightness and the opening time of windows for ventilation were examined. Making an entire building airtight results in a small reduction in energy consumption, as the air-conditioned area increases. Meanwhile, simply making an air-conditioned room airtight is more effective for reducing cooling energy consumption. Irrespective of this, nighttime ventilation of non-air-conditioned spaces is quite effective in reducing sensible cooling load. Thus, introduction of not only a high degree of insulation but also air-tightness along with well controlled ventilation is required to achieve energy savings in hot and humid climates.


windows and doors opening period (ventilation operating time), air-tightness, energy consumption for air conditioners, hot and humid climate


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