Part of the book: Planet Earth 2011
In the context of building design, as investment in the built-environment continues to grow, the requirement to deliver low-energy buildings will become ever more pressing as natural resources dwindle and consumer energy costs increase. Energy efficiency awareness and regulations continue to rise in the Gulf Cooperation Council (GCC) countries but the majority of building stock of which the larger share in energy consumption has not been designed for energy efficiency. The design and construction of buildings in hot humid climates require high-energy consumption typically for air conditioning due to higher thermal loads. Regionally, there is a rising concern on the current rate of energy consumption due to air conditioning. The global sustainability assessment system (GSAS), a performance-based system raised the bar of efficient design by the development of stringent energy passive design benchmarks on the thermal cooling need in buildings. This chapter introduces the simulation measures undertaken to reduce the cooling need using a ‘showcase’ house or the ‘near Zero Energy Home’ (nZEH), which is currently under construction. The chapter presents and discusses the Be Lean, Be Clean and Be Green strategies that used to reduce the cooling demand by more than 80% and the overall energy consumption by 75%.
Part of the book: Energy Efficient Buildings
In hot-humid climates, cooling greenhouses and barns are needed to protect crops from extremely high temperature and to ensure high-yielding dairy cows. In Qatar, outside air temperature exceeds 46°C during summer, and the wet-bulb temperature can exceed 30°C which makes greenhouses and barns unworkable during this season. This study provides theoretical and experimental data for cooling greenhouses and barns using highly efficient and low-carbon technology (QGreen). QGreen uses groundwater (geothermal) for indirect-direct evaporative cooling coupled with desiccant dehumidification. The desiccant used is seawater bittern which is a by-product of the desalination process. A desiccant indirect-direct evaporative cooling panel system is designed and analyzed. The results show that the use of groundwater will enhance the efficiency and reduce the wet-bulb temperature dramatically. As a result, the efficiency of the overall cooling system is enhanced by more than 50% compared to the direct evaporative cooling efficiency that was recorded.
Part of the book: Low Carbon Transition
Solar energy is used for a wide range of applications such as electricity production, desalination, cooling, heating, etc. Solar-based technologies are widely spread and increasingly studied in the industry. This theoretical and experimental study focuses on solar ponds as a desiccant and low-grade energy source. A thermal model has been developed for a salinity gradient solar pond (SGSP) with a non-convective zone split into 10 sub-zones. A solar pond was constructed and used as a case study for the validation of the predictive model capabilities. The dimensional characteristics of the pond, as well as the solar radiation intensity and ambient temperature data obtained from the meteorological data, were used to produce the solar pond’s zone thermal behaviour data. With regards to the thermal behaviour measurements obtained from the solar pond, the predicted data were found to be higher. There is a significant difference between the real-world and meteorological data obtained, the difference between the predicted and real-world pond temperature data was also attributed to the fact that the actual absorbed solar radiation was reduced due to wall shading effect, turbidity and insufficient duration of operation of the pond. In the following year, the stored heat from the previous summer would be expected to improve thermal storage values obtained partially.
Part of the book: Low-temperature Technologies