Design Optimization of Building Form and Fenestration for Daylighting and Thermal Energy in Three Variations of the Hot Climate of Egypt
Amany Khalil
Abstract
With the increasing in the contribution of the built environment to the climate change crisis, energy performance is becoming essential in the early design stage specially in Egypt. The building form and orientation designed at the early stage of the architectural design process can save a significant amount of the energy consumed by a building. Previous research using optimization of building form for energy performance in more than one city focused mainly on the difference between three or more climates. However, the difference between cities that are variations of the same climate is not fully studied. This research proposes a multi-objective-optimization (MOO) method of a three-floor office building in three different cities that represent variations of the Egyptian climate, namely, Cairo, Alexandria, and Aswan. This method helps architects find optimal solutions concerning thermal energy and daylighting performance while imposing genetic diversity as a third objective. Dynamic parameters are the building expansion along east-west axis, floors expansion along north-south axis, orientation, skylight, Window-to-Wall-Ratio (WWR), and shading devices. After performing the optimization, enhancements of one of overall best solutions are 19.63 %, 13.2 %, and 30.1% for annual thermal Energy Use Intensity (EUI), and 8.05%, 11.66%, and 1.54% for annual Useful Daylight Illuminance (UDI (100-2000)) in comparison to the initial squared form. The results are compared, and characteristics attributed to the specific conditions of each city are identified. Scatterplots are then developed to study the relationship between building dynamic parameters and the performance objectives. Scatterplots of floors’ expansion, building expansion and skylight show the most obvious trends in the three cities.