Abstract
In this paper, passive cooling strategies have been investigated to evaluate their effectiveness in reducing cooling thermal loads and air conditioning energy consumption for residential buildings in Kingdom of Saudi Arabia (KSA). Specifically, three passive cooling techniques have been evaluated including: natural ventilation, downdraft evaporative cooling, and earth tube cooling. These passive cooling systems are applied to a prototypical KSA residential villa model with an improved building envelope. The analysis has been carried using detailed simulation tool for several cities representing different climate conditions throughout KSA. It is found that both natural ventilation and evaporative cooling provide a significant reduction in cooling energy for the prototypical villa located in Riyadh. Natural ventilation alone has reduced the cooling energy end-use by 22% and the total villa energy consumption by 10%, while the evaporative cooling system has resulted in 64% savings in cooling energy end-use and 32% in the total villa energy consumption. When applying both passive cooling systems together to the villa, the cooling energy end use is significantly reduced by about 84.2% and the total villa energy savings by 62.3% relative to the un-insulated basecase residential building model. Moreover, natural ventilation is found to have a high potential in all KSA climates, while evaporative cooling can be suitable only in hot and dry climates such as Riyadh and Tabuk.