Li, D.H.W.; Mak, A.H.L.; Chan, W.C.; Mak, B.L.; Chen, Y.M.; Xie, H.R.; Hou, G.Q.
Bibliographic info:
The 6th International Conference on Indoor Air Quality, Ventilation & Energy Conservation in Buildings IAQVEC 2007, Oct. 28 - 31 2007, Sendai, Japan

Energy tariff is a major cost in hotel operation. Effective use of energy can reduce operationalexpenditures and has important environmental benefits. Solar heat gain particularly throughfenestration, contributes to a significant proportion of the building envelope cooling load. More solarradiation means more total solar heat gain and hence, more cooling requirements and larger electricityconsumption for air-conditioning in hot summer. Daylight makes an interior space look more lively andattractive and people expect good natural lighting in their living spaces. Daylight is alwaysaccompanied by solar heat gain. Due to the small angle of incidence, direct sunlight can be excessivefor east-facing windows in early morning and west-facing windows in late afternoon. To avoid theproblems of glare, excessive brightness and thermal discomfort, occupants may block the windowswith internal shading devices, resulting in poor daylighting performance, switching on electric lightfittings and completely isolating with the outdoor environment. Recent advances in thin film coatings forwindow glass products provide a means of substantially reducing heat gain without proportionallyreducing daylight transmittance. It indicates that cooling energy can be reduced, while people canenjoy more natural light and maintain visual contact with the outside environment. This study presentsthe optical and energy performances of a solar control film coating installed in a guest room of athree-star hotel located in Hunan Province, China. The findings indicated that solar film coating can cutdown cooling load without substantially reduce the indoor daylight illuminance level. Proper solar filmcoating designs would minimize the building energy expenditures and maintain the visual and thermalcomforts.