A Numerical Assessment of Daylight Performance of Office Buildings in Dhaka, Bangladesh: Introducing Light Shelves to Enhance Daylighting Quality

  • Nafis Sadat Department of Architecture, Faculty of Civil Engineering, Rajshahi University of Engineering and Technology, Rajshahi, Bangladesh¬
  • Nabilah Nargis Department of Architecture, Faculty of Civil Engineering, Rajshahi University of Engineering and Technology, Rajshahi, Bangladesh¬
Keywords: Daylighting, Useful Daylighting Illuminance, Light Shelves, Office Buildings, Tropical Climate

Abstract

Daylighting is one of the significant factors affecting the working environment in an office which is recognized as a vital source of energy savings. Occupants require proper daylight for desk jobs in their working spaces which largely depends on a set of internal and external aspects. This paper aims at analyzing the natural daylighting performance of the office buildings in Dhaka and providing a few design options concerning light shelves in order to enhance interior daylighting performance. A total of eleven commercial office buildings were selected in the survey based on a set of building parameters that has significant effects on daylighting. Among those selected buildings, one typical office building was further analyzed and simulated for a more detailed assessment of daylighting performance. Daylighting performance is assessed in terms of illuminance value concerning useful daylighting illuminance. The resultant data shows the inner office region lags in terms of illuminance value and is not very suitable for office works. Hence, light shelves were introduced as architectural design elements which were then simulated at different heights and angles to find out the optimum solution for daylighting enhancement which will save electrical lighting energy consumption.

References

. L. Roche, E. Dewey, and P. Littlefair, “Occupant reactions to daylight in offices,” Light. Res. Technol., vol. 32, no. 3, pp. 119–126, 2000, doi: 10.1177/096032710003200303.

. M. A. Fasi and I. M. Budaiwi, “Energy performance of windows in office buildings considering daylight integration and visual comfort in hot climates,” Energy Build., vol. 108, pp. 307–316, 2015, doi: 10.1016/j.enbuild.2015.09.024.

. “Learn about daylighting and the controlled use of natural light.” https://bit.ly/2Rv5wiY (accessed May 19, 2021).

. A. Nabil and J. Mardaljevic, “Useful daylight illuminance: A new paradigm for assessing daylight in buildings,” Light. Res. Technol., vol. 37, no. 1, pp. 41–59, 2005, doi: 10.1191/1365782805li128oa.

. HBRI, “Bangladesh National Building Code,” Hous. Build. Resaerch Inst., vol. 1, 2015, [Online]. Available: https://www.bnbc2020.com.

. D. H. W. Li and E. K. W. Tsang, “An analysis of daylighting performance for office buildings in Hong Kong,” Build. Environ., vol. 43, no. 9, pp. 1446–1458, 2008, doi: 10.1016/j.buildenv.2007.07.002.

. A. R. Joarder, Z. N. Ahmed, A. Price, and M. Mourshed, “A simulation assessment of the height of light shelves to enhance daylighting quality in tropical office buildings under overcast sky conditions in Dhaka, Bangladesh,” IBPSA 2009 - Int. Build. Perform. Simul. Assoc. 2009, pp. 1706–1713, 2009.

. [A. M E, “daylighting systems : An experimental evaluation,” Light. Res. Technol., pp. 141–152.

. X. Yu and Y. Su, “Daylight availability assessment and its potential energy saving estimation -A literature review,” Renew. Sustain. Energy Rev., vol. 52, pp. 494–503, 2015, doi: 10.1016/j.rser.2015.07.142.

. “useful daylight illuminance (UDI) – Illuminating Engineering Society.” https://bit.ly/3tVLDic (accessed May 19, 2021).

. Latlong, “Dhaka, Bangladesh Geographic Information,” 2017. https://www.latlong.net/place/dhaka-bangladesh-718.html.

. P. R. Tregenza, “Measured and calculated frequency distributions of daylight illuminance,” Light. Res. Technol., vol. 18, no. 2, pp. 71–74, 1986, doi: 10.1177/096032718601800202.

. H. Lee, S. Park, and J. Seo, “Development and Performance Evaluation of Light Shelves Using Width-Adjustable Reflectors,” Adv. Civ. Eng., vol. 2018, 2018, doi: 10.1155/2018/2028065.

. P. K. Soori and M. Vishwas, “Lighting control strategy for energy efficient office lighting system design,” Energy Build., vol. 66, pp. 329–337, 2013, doi: 10.1016/j.enbuild.2013.07.039.

Published
2021-07-02
Section
Articles