Towards greener buildings: A review on the role of fluidic windows with embedded microfluidic channels for energy saving in the building setups

In modern buildings, windows and facades are significant sources of energy inefficiency that account for 40% of the energy cost of the entire building due to the thermal energy loss during both summer and winter in terms of heat gain and heat loss. This further increases the energy expenditure of the heating, ventilation, and air-conditioning (HVAC) system. To address this issue, double-glazed windows are converted into liquid-filled tunable window systems, where the heat in-flux and out-flux to the room can be regulated by adjusting flow properties. Researchers have recently focused their attention on integrating microfluidic technologies into fluidic windows for the transport of fluid, as it demonstrated superior performance in terms of energy recovery and adaptive lighting. The objective of this review is to summarize engineering perspectives and recent progress in the design and efficiency of fluidic window systems with a particular emphasis on the advantages of integrating microfluidics. In this study, a comprehensive metadata analysis was conducted based on the obtained literature from the Scopus database. A description of the numerical methods, experimental setup, material properties, influence of microfluidic integration to the building’s facade system, advantages, disadvantages, and future perspectives of these fluidic window systems is provided in detail.