Abstract
Buildings in Saudi Arabia consumes approximately 80% of the electricity generated in the country. Saudi Arabia's hot, arid climate, with summer temperatures frequently exceeding 45 degrees C, means that air conditioning uses nearly 50% of the country's electricity, and virtually all the electricity is generated from fossil fuels. Passive cooling techniques could be a sustainable alternative to conventional air-conditioning systems when integrated properly within a building. A Passive Downdraught Evaporative Cooling (PDEC) tower is considered as one of the most efficient passive systems and was investigated in this study. A single storey open plan room with a PDEC tower was digitally modelled and then changes in wind direction and architectural form were simulated to see the effect on the PDEC performance. IES VE software was selected for the simulations as it can conduct a dynamic thermal simulation for PDEC systems. A weather file for Riyadh was obtained from the software Meteonorm. The study demonstrated that significant cooling can be achieved by PDEC towers, but that their effectiveness was greatly reduced by changes in wind direction linked to opening distributions in the room attached to the PDEC tower.