Ahmadreza Keshtkar Ghalati - Department of Architecture, Faculty of Art and Architecture, Kharazmi University, Tehran, Iran.
Mahdieh Ahmadian - Rassam Institute of Higher Education, Karaj, Iran.

Light shelves not only create shade but also improve the uniformity of daylight. In addition to saving energy, they can improve the lighting quality of a space. This research aims to position light shelves and deep windows to enhance energy efficiency and daylight illuminance in classrooms in Abadan (Iran) with hot and dry climates. Rhino/Grasshopper software and Ladybug/Honeybee plugins were used to model and evaluate visual comfort and EUI. By comparing the types of external, internal, and central shelves and in different situations of window depth, the following results were obtained: By combined use of light shelves and deep windows: In central light shelves, energy consumption decreased by ۲۰%, and glare effects were reduced by ۵۳.۳۷%. As a result, installing a window in the depth of the wall did not have much effect on reducing energy consumption, but to some extent, it controlled the intensity of glare. The deep window has reduced energy consumption (۱۳%), and using light shelves has improved energy performance (۱۴ to ۲۰%). Compared to the base model, the combined light shelves reduced UDI by ۲۰% and glare by ۵۳%, while the inside light shelves reduced UDI by ۱۴% and glare by ۳۰%. Therefore, installing light shelves always reduces glare. But if the intention is to save energy, the central and external light shelves in the position of the deep window are very useful.

Light shelves, Deep windows, EUI, UDLI, Daylight