Comparative Evaluation of Facade-Based Water Harvesting Technologies for Sustainable Buildings in India's Arid Climate
Abstract: India's arid and semi-arid regions, including the Thar Desert, Kutch, and Marwar tracts, are experiencing accelerating groundwater depletion, with national assessments indicating that a majority of monitored wells show declining levels [1]. While rooftop rainwater harvesting is widely implemented and mandated by several state governments, the vertical building envelope remains a comparatively unexploited water-harvesting surface, despite its large exposed area in dense urban settings. This paper undertakes a comparative evaluation of facade-integrated water harvesting approaches, namely fog harvesting, dew and passive radiative condensation, sorption-based atmospheric water generation, and biomimetic surface enhancement, assessed alongside traditional and contemporary vertical rainwater channeling. A multi-criteria comparative framework is constructed from published technical performance, climatic suitability, architectural integration, and cost data, and applied to representative Indian arid climate zones. It is found that dew-based radiative condensation shows the strongest evidence base for Indian conditions, given documented field trials in Gujarat, while sorption-based atmospheric water generation, though still emerging at building scale, is best suited to the very low relative humidity conditions typical of interior arid tracts. Fog harvesting is found to be climatically restricted to coastal or orographic-fog locations, and vertical rainwater channeling, informed by vernacular precedent, is found to remain the most cost-effective and technically mature option. A technology-selection framework linked to micro-climatic zoning is proposed for architects and building planners.
Keywords: facade water harvesting, atmospheric water harvesting, arid climate, sustainable buildings, building envelope, dew harvesting, India
How to Cite?: Abha Gupta, "Comparative Evaluation of Facade-Based Water Harvesting Technologies for Sustainable Buildings in India's Arid Climate", Volume 15 Issue 10, October 2026, International Journal of Science and Research (IJSR), Pages: 941-945, https://www.ijsr.net/getabstract.php?paperid=SR26727234332, DOI: https://dx.doi.org/10.21275/SR26727234332