Toplighting and energy saving implications for classrooms in Muscat-oman

Open Access
Al-jahadhmy, Nablus Ali
Graduate Program:
Architectural Engineering
Master of Science
Document Type:
Master Thesis
Date of Defense:
April 09, 2015
Committee Members:
  • Richard George Mistrick, Thesis Advisor
  • Daylight
  • Toplighting
  • Skylight
  • Clerestory
  • Monitor
  • Visible Light Transmittance (Tvis)
  • Light to Solar Gain (LSG)
  • Solar Heat Gain Coefficient (SHGC)
  • Skylight to Roof Ratio (SRR
  • energy savings
  • energy consumption
One of the driving forces for a country's economy is its energy consumption. With a rise in electricity prices, fossil fuels being a finite resource, and their major role in producing greenhouse gas emissions (Environmental Protection Agency, 2013), it is important to minimize energy use and or convert to alternative energy sources. The use of natural daylight for lighting the interior of buildings can reduce prime energy demand and lower negative impacts on the environment. This research study provides some design guidance of toplighting systems for school classrooms in hot climates such as in Muscat, Oman. This work can serve to advice not only engineers, but also architects by providing an understanding of the relationship between daylight delivered through rooftop fenestration systems and the heat gain resulting from these systems. Usually, for architects, the focus is on building design and less emphasis is placed upon building performance and its effectiveness. Integration of energy simulation tools into the design process can help assess the performance of toplighting and its correlation to energy savings within a space. The aim of this study is to assess appropriate daylighing conditions that do not significantly over-light a space while providing a favorable energy balance between cooling and electrical lighting loads. A classroom analysis of a 9 meter (30 feet) wide by 7.6 meter (25 feet) deep by 3 meter (10 feet) high space was conducted using two simulation programs: DAYSIMps and IES-VE. Three types of rooftop fenestration were analyzed: skylights, clerestory roof monitors, and roof monitor. Standards for the base model follow the ASHRAE 90.1/ IESNA 2013 prescriptive fenestration guidelines. Aperture placement, glazing type, size, and shape are variables that determine illumination and heat gain levels present in the classroom. Adjustments to these parameters were analyzed and compared to the baseline model with no toplighting fenestration in order to assess illumination, glare, energy, and savings response.