Envelope retrofit and air-conditioning operational strategies for reduced energy consumption in mosques in hot climates

Thermal performance of buildings is mainly determined by their thermo-physical and operational characteristics as well as the prevailing climatic conditions. Mosques which represent a unique type of building in terms of construction and operation can be major consumers of cooling energy, particularly in hot climates, if not properly designed and operated. In this study, energy modeling and simulation is utilized to identify potential energy savings due to envelope retrofitting measures and air-conditioning (A/C) operational strategies while maintaining acceptable thermal conditions. Results revealed a good potential for energy reductions when proper thermal retrofitting and operational strategies are employed. As much as 26% reduction in annual cooling energy is obtained when applying roof and wall insulation and reducing air infiltration to 0.5 ACH. By implementing a proper A/C operational strategy and employing system efficiency improvements, the required cooling energy can be reduced by around 36%. The total reduction in cooling energy consumption due to combined A/C system and envelope retrofit measures can be as much as 48%. A number of recommendations pertaining to mosque design, retrofitting and A/C operational strategies are derived. These are expected to be of great use to mosque designers and operators worldwide, but particularly in hot climates.