Indoor Thermal Performance of a Retrofitted Air-Conditioned Mosque: Case Study for Penang State Mosque

In a mosque environment, occupants are temporarily in the situation of various dress and congregate activities which desire comfortable environment. Inappropriate thermal comfort condition in a mosque leads the distraction in fulfilling the religious practice and also causing emotional influence. The proper setting of thermal comfort parameters is important to provide a suitable environment for the mosque occupants. Proper investigations of thermal comfort may help to optimize the usage of the cooling systems such as air conditioning system. The objective of this paper is to investigate the thermal comfort performance of large-scale retrofitted air-conditioned mosques with intermittent operation in Penang, Malaysia. According to the survey, the mosques in this region can be categorized into five groups (G1 –G5) according to floor area (131.55 m^2 to 2,920 m^2). A case study is conducted on a large scale mosque with a floor area of 2,920 m^2 that is equipped with a centralized air-conditioning system. Result shows that the system produces an indoor thermal environment that within the range recommended by ASHRAE Standard 55. Most of the predicted thermal sensation under predicted mean vote (PMV) indices is achieved and within the comfort zone range (-0.5, +0.5). Some thermal strategies need to be applied especially on air conditioning system, operation configuration, handling procedure, zoning section as well as technical knowledge among mosque officials. Hence, the energy consumption of the mosque can be reduced while maintaining thermal comfort level of occupants.