Numerical study on the thermal performance of water flow window fed with air-conditioning condensate

• Published in: Energy (Oxford) 2023-01, Vol.263, p.125633, Article 125633
• Main Author: Chan, Lok Shun
• Format: Article
• Language: English
• Subjects: Building energy simulation; Condensate recovery; Water flow window
• ISSN: 0360-5442
• DOI: 10.1016/j.energy.2022.125633

A water flow window (WFW) fed with potable water is deemed as an effective system for absorbing incoming heat energy through the glazing area of a window. In this study, condensate formed in an air-conditioning (A/C) system is applied in a WFW for reducing heat gain and electricity consumption of a building. There is no need to consume any potable water. Through building energy simulations and numerical computation, this study unveils that a fully air-conditioned office building operating under a subtropical climate can produce condensate of sufficient flow rate to absorb heat energy from the glazing panes of an A/C condensate fed WFW system. The surface temperature of an outer glazing pane in an A/C condensate fed WFW system can be dropped by 16.3 °C when compared to a Low-e glass window. Moreover, an A/C condensate fed WFW can offer better thermal performance than a conventional WFW. When comparing to a Low-e glass case, an A/C condensate fed WFW facing four different orientations (N, E, S & W) can give reduction percentages of transmitted heat gain ranging from 57.2% to 63.5%. This A/C condensate fed WFW system shows a promising performance and has good potential for real application in commercial buildings. •Water flow window fed with air-conditioning condensate (A/C condensate WFW).•Application of A/C condensate WFW in buildings under subtropical climate condition.•The surface temperature of an A/C condensate WFW can be decreased by 16.3 °C.•The reduction percentages in transmitted heat gain range from 57.2% to 63.5%.•The A/C condensate WFW system has a good potential for application in buildings.