Energy savings from the shading performance of devices in highly glazed multi-story office buildings in the tropical climates of China and India
Rapid urbanization in China and India has led to the widespread development of high-rise office buildings with highly glazed façades in tropical climates, increasing the need for energy-efficient design strategies. Exterior shading systems can significantly enhance building energy performance by regulating solar heat gain in cooling-dominated climates. However, a systematic strategy is required to evaluate the energy-saving potential of such systems during the design phase. This study investigates the impact of shading fraction (SF) on space cooling load through simulation-based methods in two major tropical climate zones of Asia. Two Köppen climate types are examined: humid subtropical (Cwa), represented by Hong Kong (China) and New Delhi (India); and tropical wet and dry (Aw), represented by Haikou (China) and Chennai (India). The tools employed include Revit for geometry modeling, Dynamo for shaded area calculation, and E-Quest for energy simulation. A custom Dynamo script was developed to calculate the hourly shaded area of horizontal and vertical fins by varying fin depth. These were categorized into five SF levels (45–95%) at 10% intervals for four orientations and four representative seasonal days. Hourly cooling energy demand for each SF case was compared to a base model without shading. Results show cooling load savings ranging from 6% to 14% across locations: Chennai (9–14%), New Delhi (7–13%), Hong Kong (6–13%), and Haikou (8–14%). Despite identical climate classifications, Indian cities showed higher savings due to higher mean monthly temperatures. These findings offer valuable guidance for climate-responsive shading design in highly glazed tropical buildings.
Al-Masrania, S. M., Al-Obaidi, K. M., Zalina, N. A., & Aida Isma, M. I. (2018). Design optimisation of solar shading systems for tropical office buildings: Challenges and future trends. Energy, 170:849-872. https://doi.org/10.1016/j.solener.2018.04.047
Bano, F., & Kamal, M. A. (2016). Examining the role of building envelope for energy efficiency in office buildings in India. Architecture Research, 6(5):107-115. https://doi.org/10.5923/j.arch.20160605.01
Bazazzadeh, H., Świt-Jankowska, B., Fazeli, N., Nadolny, A., Safar Ali Najar, B., Hashemi Safaei, S. S., et al. (2021). Efficient Shading device as an important part of daylightophil architecture; a designerly framework of high-performance architecture for an office building in tehran. Energies, 14(24):8272. https://doi.org/10.3390/en14248272
Bhattacharya, A., Kar, S., & Bhattacharya, R. (1996). Diffuse solar radiation and associated meteorological parameters in India. Annales Geophysicae, 14(10):1051-1059. https://doi.org/10.1007/s005850050366
Chandrasekaran, C. (2020). Envelope Performance Analysis of Office Buildings in Warm and Humid Climate: From Case Studies of Multi-storied Office Buildings in Chennai. Singapore: Sustainable Urban Architecture Springer. https://doi.org/10.1007/978-981-15-9585-1
Choi, S. J., Lee, D. S., & Jo, J. H. (2017). Method of deriving shaded fraction according to shading movements of kinetic façade. Sustainability, 9(8):1449. https://doi.org/10.3390/su9081449
Chown, S. L., Hoffmann, A. A., Kristensen, T. N., Angilletta, M. J. Jr., Stenseth, N. C., & Pertoldi, C. (2010). Adapting to climate change: A perspective from evolutionary physiology. Climate Research, 43:3-15. https://doi.org/10.3354/cr00879
Darwin, N. (2019). Parametric Design with Visual Programming in Dynamo with Revit The Conversion from CAD Models to BIM and the Design of Analytical Applications. [Master Thesis]. Brinellvägen, Sweden Stockholm: KTH Royal Institute of Technology.
Gronbeck, C. (2016). Sustainable by Design. Available from: https://www.susdesign.com/overhang_annual/index.php [Last accessed on 2025 Mar 10].
Hien, W. N., & Istiadji, A. D. (2003). Effects of External Shading Devices on Daylighting and Natural Ventilation. In: Proceedings of the 8th International IBPSA Conference, Eindhoven, The Netherlands, p. 475-482.
Hiller, M. D. E., Beckman, W. A., & Mitchell J. W., (2000). TRNSHD - a shading and isolation calculations program. Building and Environment, 35:633-644.
Johnsen, K., & Winther, F. V. (2015). Dynamic façades, the smart way of meeting the energy requirements, Energy Procedia, 78:1568-1573. https://doi.org/10.1016/j.egypro.2015.11.210
Kent, M. G., Altomonte, S., Wilson, R., & Tregenza, P. R. (2017). Temporal effects on glare response from daylight. Building and Environment, 113:49-64. https://doi.org/10.1016/j.buildenv.2016.09.002
Kim, H., Asl, M. R., & Yan,W. (2015). Parametric BIM-Based Energy Simulation for Buildings with Complex Kinetic Façades. In: 33rd eCAADe Conference. Vol. 1. Vienna, Austria: Vienna University of Technology.
Maestre, I. R., Pérez-Lombard, L., Foncubierta, J. L., & Cubillas, P. R. (2013). Improving direct solar shading calculations within building energy simulation tools. Build. Perform. Simulation, 6:437-448.
Murta, A. (2015). GPC: General Polygon Clipper Library. Astrophysics Source Code Library, p. 1512.
Pongpattana, C., & Rakkwamsuk P. (2006). Efficient algorithm and computing tool for shading calculation. Songklanakarin Journal of Science and Technology, 28(2):375-386.
Ying, H., Liu, X., & Chang, L. (2014). Comparison of software for building energy simulation. Journal of Chemical and Pharmaceutical Research, 6(3):467-471.