Design Guidelines for Thermal Comfort and Energy Consumption of Triple Glazed Fluidic Windows on Building Level

Abstract

AbstractThere has been a growing trend for buildings with large glazing size. As a trade‐off, this comes with enhanced solar heat input and/or reduced thermal insulation. Several approaches are being followed to reduce the energy consumption in these buildings, including the prolific field of smart windows. In a previous report, a fluidic window device for thermal harvesting and air‐conditioning was introduced. Using this example, the impact of a building's window‐to‐wall ratio on the triple glazed fluidic window's energy consumption and user thermal comfort is evaluated, providing design guidelines for large‐scale implementation of such smart windows with real‐world buildings. The analysis shows that the proposed window design reduces the primary energy demand as compared to using a conventional air‐conditioning system. Building simulation results indicate that the system enables satisfying thermal comfort for buildings with different window‐to‐wall ratios. Although a higher window‐to‐wall ratio improves the heat pump efficiency, it requires more heating and cooling energy. On‐device photovoltaic modules may be used for changing this relationship. In this case, the proposed device may become self‐sufficient once the transfer efficiency is high enough. It is argued that similar considerations should be applied to other types of smart window technologies.