Journal of Energy Management and Technology

Journal of Energy Management and Technology

Optimum Dimensions of Windows to Improve Daylight and Energy Consumption of Educational Buildings in Hot and Dry Climate, A Case Study of Yazd City

Document Type : Original Article

Authors
ahmadreza Keshtkar Ghalati 1
Roya Tabatabaeiyan 2
1 Assistant Professor of Architecture, Faculty of Arts and Architecture, Kharazmi University, Tehran, Iran.
2 Graduated with a master’s degree of Architecture and Energy, Rassam Institute of Higher Education, Karaj, Iran
10.22109/jemt.2025.474179.1524
Abstract
Today, reducing energy consumption is one of the global concerns of preserving resources and the environment. The building industry is the main consumer of energy among all industries, so reducing energy consumption in this sector is important. This research aims to optimize the dimensions of windows in educational buildings to improve the quality of daylight and energy consumption, and for this purpose, one of the most important parameters, i.e. window-to-wall ratio, has been evaluated. Due to the parametric nature of the simulations, the software Rhino-Grasshopper plugin has been used to build the initial parametric model. Honeybee and Ladybug plugins have been used to simulate energy and light due to the use of the validated Energy Plus engine for thermal calculations. The results showed that the energy consumption of the building improved by about 12%, and the useful brightness of daylight improved by about 38% after optimization. The optimal size of the window-to-wall ratio for classrooms that received southeast and northwest light was about 25%, and for classrooms that received northeast light, about 20%.  
Keywords
Educational buildings, Reducing energy consumption
Hot and dry climate
Window dimensions
Daylight

Subjects

  1. Watts, W. N. Adger, P. Agnolucci, J. Blackstock, P. Byass, W. Cai, S. Chaytor, T. Colbourn, M. Collins, A. Cooper, and others, “Health and climate change: Policy responses to protect public health”, Lancet, vol. 386, pp. 1861–1914, 2015. https://doi.org/10.1016/s0140-6736(15)60854-6
  2. King, J. Browne, R. Layard, G. O’Donnell, M. Rees, N. Stern, and A. Turner, “A global Apollo programme to combat climate change”, Centre for Economic Performance, London School of Economics and Political Science, London, 2015.
  3. Pérez-Lombard, J. Ortiz, and C. Pout, “A review on buildings energy consumption information”, Energy and Buildings, vol. 40, no. 3, pp. 394–398, 2008. https://doi.org/10.1016/j.enbuild.2007.03.007
  4. Ghermezi and F. Nasrollahi, “Daylight efficiency solutions using architectural patterns to save energy in Isfahan city schools”, in Proceedings of the 2nd Iran International Lighting Conference, Tehran, 2014.
  5. Heydari, Architecture and Lighting, University of Tehran Publications, Tehran, 2012.
  6. Department of Education and Science (DES), Lighting in Schools, Building Bulletin No. 33, HMSO, London, 1967 and 1981.
  7. Zomorodian, F. Nasrollahi, and M. Aliabadi, “Reducing energy consumption in schools with optimal design of windows and canopies: A case study of Shiraz schools”, in Proceedings of the 2nd National Conference on Climate, Building and Optimization of Energy Consumption, Shiraz, 2013.
  8. Research Centre, Lighting Standard, Iranian Building Code, vol. 19: Lighting, Ministry of Building and Urban Design, Tehran, 1992.
  9. Ghermezi and F. Nasrollahi, “Effect of building depth on the energy consumption of educational buildings in Isfahan city”, in Proceedings of the 1st International Congress of Interdisciplinary Science Researches in Urban Planning and Architecture, Isfahan, 2016.
  10. Hafizi, Z. Zomorodian, and M. Tahsildoost, “Process of obtaining a two-layer facade with appropriate energy efficiency: A case study in Tehran”, Journal of Iranian Architecture Studies, vol. 1, no. 10, pp. 1–10, 2015. https://doi.org/10.1016/j.enbuild.2016.09.059
  11. J. Sorgato, A. P. Melo, and R. Lamberts, “The effect of window opening ventilation control on residential building energy consumption”, Energy and Buildings, vol. 133, pp. 1–13, 2016.
  12. Li, J. Tan, T.-T. Chow, and Z. Qiu, “Experimental and theoretical study on the effect of window films on building energy consumption”, Energy and Buildings, vol. 102, pp. 129–138, 2015. https://doi.org/10.1016/j.enbuild.2015.04.025
  13. Wang and S. Greenberg, “Window operation and impacts on building energy consumption”, Energy and Buildings, vol. 92, pp. 313–321, 2015. https://doi.org/10.1016/j.enbuild.2015.01.060
  14. Cuce and S. B. Riffat, “A state-of-the-art review on innovative glazing technologies”, Renewable and Sustainable Energy Reviews, vol. 41, pp. 695–714, 2015. https://doi.org/10.1016/j.rser.2014.08.084
  15. Huang, J.-L. Niu, and T.-M. Chung, “Comprehensive analysis on thermal and daylighting performance of glazing and shading designs on office building envelope in cooling-dominant climates”, Applied Energy, vol. 134, pp. 215–228, 2014. https://doi.org/10.1016/j.apenergy.2014.07.100
  16. P. Jelle, A. Hynd, A. Gustavsen, D. Arasteh, H. Goudey, and R. Hart, “Fenestration of today and tomorrow: A state-of-the-art review and future research opportunities”, Solar Energy Materials and Solar Cells, vol. 96, pp. 1–28, 2012. https://doi.org/10.1016/j.solmat.2011.08.010
  17. W. Lockley, “Circadian rhythms: Influence of light in humans”, in Encyclopedia of Neuroscience, Elsevier, Oxford, pp. 971–988, 2009. http://dx.doi.org/10.1016/B978-008045046-9.01619-3
  18. Rashid and C. Zimring, “A review of the empirical literature on the relationships between indoor environment and stress in health care and office settings: Problems and prospects of sharing evidence”, Environment and Behavior, vol. 40, pp. 151–173, 2008. http://dx.doi.org/10.1177/0013916507311550
  19. Edwards and P. Torcellini, “A literature review of the effects of natural light on building occupants”, National Renewable Energy Laboratory, Golden, CO, 2002. http://dx.doi.org/10.2172/15000841
  20. D. Galasiu and J. A. Veitch, “Occupant preferences and satisfaction with the luminous environment and control systems in daylit offices: A literature review”, Energy and Buildings, vol. 38, pp. 728–742, 2006. https://doi.org/10.1016/j.enbuild.2006.03.001
  21. J. Gago, T. Muneer, M. Knez, and H. Köster, “Natural light controls and guides in buildings: Energy saving for electrical lighting, reduction of cooling load”, Renewable and Sustainable Energy Reviews, vol. 41, pp. 1–13, 2015. https://doi.org/10.1016/j.rser.2014.08.002
  22. T. Doulos, A. Tsangrassoulis, and F. V. Topalis, “Multi-criteria decision analysis to select the optimum position and proper field of view of a photosensor”, Energy Conversion and Management, vol. 86, pp. 1069–1077, 2014. https://doi.org/10.1016/j.enconman.2014.06.032
  23. T. Doulos, A. Tsangrassoulis, P. A. Kontaxis, A. Kontadakis, and F. V. Topalis, “Harvesting daylight with LED or T5 fluorescent lamps? The role of dimming”, Energy and Buildings, vol. 140, pp. 336–347, 2017. https://doi.org/10.1016/j.enbuild.2017.02.013
  24. T. Doulos, A. Tsangrassoulis, and F. V. Topalis, “Quantifying energy savings in daylight responsive systems: The role of dimming electronic ballasts”, Energy and Buildings, vol. 40, pp. 36–50, 2008. https://doi.org/10.1016/j.enbuild.2007.01.019
  25. Lee, S. Kim, and J. Seo, “Evaluation of a light shelf based on energy consumption for lighting and air conditioning”, Indoor and Built Environment, vol. 27, no. 10, pp. 1405–1414, 2017. http://dx.doi.org/10.1177/1420326X17719954
  26. F. Reinhart, “A simulation based review on the ubiquitous window head height to daylit zone depth rule of thumb”, in Proceedings of the 9th International IBPSA Conference, Montréal, Canada, pp. 15–18, 2005.
  27. EN 15193-1, Energy Performance of Buildings – Energy Requirements for Lighting, European Committee for Standardization, 2017. https://shop.bsigroup.com/ProductDetail?pid=000000000030292858
  28. F. Reinhart and V. R. M. LoVerso, “A rules of thumb-based design sequence for diffuse daylight”, Lighting Research and Technology, vol. 42, no. 1, pp. 7–31, 2010. https://doi.org/10.1177%2F1477153509104765
  29. Konstantoglou and A. Tsangrassoulis, “Dynamic operation of daylighting and shading systems: A literature review”, Renewable and Sustainable Energy Reviews, vol. 60, pp. 268–283, 2016. https://doi.org/10.1016/j.rser.2015.12.246
  30. Bellia, C. Marino, F. Minichiello, and A. Pedace, “An overview on solar shading systems for buildings”, Energy Procedia, vol. 62, pp. 309–317, 2017. https://doi.org/10.1016/j.egypro.2014.12.392
  31. S. Mayhoub, “Innovative daylighting systems’ challenges: A critical study”, Energy and Buildings, vol. 80, pp. 394–405, 2014. https://doi.org/10.1016/j.enbuild.2014.04.019
  32. E. Aizlewood, “Innovative daylighting systems: An experimental evaluation”, Lighting Research and Technology, vol. 25, pp. 141–152, 1993. https://doi.org/10.1177%2F096032719302500401
  33. Kherdmandi and S. B. Hosseini, “Investigating the effect of window size and shape on energy consumption in educational spaces”, in Proceedings of the 2nd International Congress of Structures, Architecture and Urban Development, Tabriz, 2013.
  34. Lartigue, B. Lasternas, and V. Loftness, “Multi-objective optimization of building envelope for energy consumption and daylight”, Indoor and Built Environment, vol. 23, no. 1, pp. 70–80, 2014. https://doi.org/10.11771420326/X1348022
  35. M. A. Melendo and P. Roche, “Effects of window size in daylighting and energy performance in buildings”, in Proceedings of the PLEA Conference, 2017.
  36. M. Koohsari, R. Fayaz, and B. Mohammad Kari, “The influence of window dimensions and location on residential building energy consumption by integrating thermal and lighting analysis in a mild and humid climate”, BRIS Journal of Advances in Science and Technology, vol. 3, pp. 187–194, 2015.
  37. J. Dabe and A. R. Dongre, “Analysis of performance of the daylight into critical liveable area of ‘type design’ dwelling unit on the basis of daylight metrics for hot and dry climate”, Indoor and Built Environment, vol. 27, no. 1, pp. 129–142, 2018. http://dx.doi.org/10.1177/1420326X16669844
  38. -W. Lee, H.-J. Jung, J.-Y. Park, J. B. Lee, and Y. Yoon, “Optimization of building window system in Asian regions by analyzing solar heat gain and daylighting elements”, Renewable Energy, vol. 50, pp. 522–531, 2013. https://doi.org/10.1016/j.renene.2012.07.029
  39. Akhtarkavan and S. Shafiee, “Effect of window dimensions on daylighting and energy consumption in residential complexes of hot and dry climate of Iran: Case study of Isfahan City”, Armanshahr Architecture and Urban Development, vol. 16, no. 42, pp. 17–30, 2023. https://doi.org/10.22034/aaud.2021.174175.1822
  40. Barzanouni, R. Fayaz, and S. B. Hosseini, “The effect of window dimensions on lighting and thermal energy in office buildings in hot arid climate”, Journal of Architecture and Urban Planning, vol. 16, no. 42, pp. 25–44, 2024. https://doi.org/10.30480/aup.2022.3837.1828
  41. Khanmohamadi M, Pourahmadi M, Mozaffar F. Windows optimization based on the glare performance in educational building of Iran hot and dry climate. J Sustain Archit Urban Des. 2019;7(1):113-28. https://doi.org/10.22061/jsaud.2019.4362.1302
  42. Heirani Pour M, Fayaz R, Mahdavinia M. Optimization of window dimensions regarding light and heat parameters in residential buildings of cold climate; case study: Ilam City. Armanshahr Archit Urban Dev. 2021;14(35). https://doi.org/10.22034/aaud.2019.185696.1881
  43. Ghiabaklou Z. Fundamentals of building physics 5 (Daylighting). Tehran: University Jihad Organization Publications; 2013.
  44. Heidari SH. Architecture and lighting. Tehran: Tehran University Press; 2001.
  45. Ochoa CE, Aries MB, Van Loenen EJ, Hensen JL. Considerations on design optimization criteria for windows providing low energy consumption and high visual comfort. Appl Energy. 2012;95:238-45. https://doi.org/10.1016/j.apenergy.2012.02.042
  46. Goia F. Search for the optimal window-to-wall ratio in office buildings in different European climates and the implications on total energy saving potential. Sol Energy. 2016;132:467-92. https://doi.org/10.1016/j.solener.2016.03.031
  47. Scott C, Bekker A, Reinhard C, Lyons TW. Late Archean euxinia as a window into early biogeochemical cycles. AGU Fall Meeting Abstracts. 2009;B13A-0510. https://ui.adsabs.harvard.edu/#abs/2009AGUFM.B13A0510S/abstract
  48. Montaser Koohsari A, Fayaz R, Mohammad Kari B. Window dimension optimization on the south side of moderate and wet climate residential buildings to achieve sustainable architecture. Proc 2nd Int Cong Struct Archit Urban Dev. Tabriz; 2014.
  49. Alwetaishi M. Impact of glazing to wall ratio in various climatic regions: A case study. J King Saud Univ Eng Sci. 2019;31(1):6-18. https://doi.org/10.1016/j.jksues.2017.03.001
  50. Jensen SØ. Validation of building energy simulation programs: a methodology. Energy Build. 1995;22(2):133-44. https://doi.org/10.1016/0378-7788(94)00910-C
  51. Witte MJ. Algorithms for modeling multiple air handling units serving the same zone in EnergyPlus. Proc Build Simul Conf. 2019;3:1539-44. http://dx.doi.org/10.26868/25222708.2019.211176
  52. Queiroz N, Westphal FS, Ruttkay Pereira FO. A performance-based design validation study on EnergyPlus for daylighting analysis. Build Environ. 2020;183:107088. https://doi.org/10.1016/j.buildenv.2020.107088
  53. Givoni B. Conservation and the use of integrated-passive energy systems in architecture. Energy Build. 1981;3(3):213-27. https://doi.org/10.1016/0378-7788(81)90007-4
  54. Parasonis J, Keizikas A. Possibilities to reduce the energy demand for multi-storey residential buildings. Proc 10th Int Conf Modern Build Mater Struct Tech. VGTU: Technika; 2010. p. 989-93.
  55. Kialashki Mohsen M, Ghermezi M. Feasibility of using solar energy in supplying electricity to schools in Isfahan city. Proc 1st Natl Conf Future City. Tehran; 2014.
  56. Parasonis J, Keizikas A, Endriukaitytė A, Kalibatiene D. Architectural solutions to increase the energy efficiency of buildings. J Civil Eng Manag. 2011;18(1):71-80. http://dx.doi.org/10.3846/13923730.2011.652983
  57. Zomorodian Z. Evaluation of architectural solutions to reduce energy consumption in primary schools in Shiraz [Master’s thesis]. Shiraz: Shiraz University; 2013.
  58. Keshtkaran P, Karimzadeh A. Principles of sustainable school design in order to achieve sustainable architecture and save energy consumption. Proc Natl Conf Archit Educ Spaces. 2014.
  59. Babaifar Z, Nikpour M. Using daylight in educational spaces. Proc Int Conf Civil Eng Archit Urban Infrastruct. Tabriz; 2015.
  60. Gorji Mahlabani Y, Feizi M, Khakzand M. Lighting programme and Iranian schools lighting requirements. Int J Archit Eng Urban Plan. 2011;0(2):1-11. http://ijaup.iust.ac.ir/article-1-73-en.html
  61. Shafavi Moghaddam N, Zomorodian Z, Tahsildoost M. Ability of daylight indicators in estimating adequate lighting in space based on user assessments: Case study of architecture design studios in Tehran. Soffeh. 2019;29(3):37-56. https://dx.doi.org/10.29252/soffeh.29.3.37
  62. Ghiabaklou Z. Basics of building physics: Daylight. Tehran: Jihad University Publications, Amirkabir Industrial Unit; 2012.
  63. Lechner N. Heating, cooling, and lighting: Sustainable design methods for architects. 3rd ed. Hoboken: John Wiley & Sons; 2009.
  64. Sharifi H, Khabiri O. Optimal use of sunlight in schools with solar architecture approach. Proc 3rd Natl Conf Sustain Dev Geogr Plan Archit Urban Plan. Tehran; 2014.
  65. Montaser Koohsari A, Fayaz R, Mohammad Kari B. Optimizing window size and its sunshade in four main directions of residential buildings in mild climate by integrating thermal and lighting analysis. J Renew Energy Environ. 2016;3(2):1-14. https://dx.doi.org/10.30501/jree.2016.70080
  66. Troup L, Philips R, Eckelman M, Fannon D. Effect of window-to-wall ratio on measured energy consumption in US office buildings. Energy Build. 2019;203:109434. http://dx.doi.org/10.1016/j.enbuild.2019.109434
  67. Acosta I, Campano MA, Domínguez S, Fernández-Agüera J. Minimum daylight autonomy: A new concept to link daylight dynamic metrics with daylight factors. Leukos. 2019;15(4):251-69. https://doi.org/10.1080/15502724.2018.1564673
Journal of Energy Management and Technology
Volume 9, Issue 2
Spring 2025
Pages 110-120

  • Receive Date 19 August 2024
  • Revise Date 13 January 2025
  • Accept Date 22 July 2025