Building energy performance of DSSC BIPV windows in accordance with the lighting control methods and climate zones

This study was aimed at analyzing the total energy consumption associated with different lighting control methods when dye-sensitized solar cell (DSSC) building-integrated photovoltaic (BIPV) windows were installed in office buildings in various climate zones. The total energy consumption and power generation efficiency of the DSSCs were analyzed to determine the power generation efficiency standards that could facilitate energy con-servation within a target building. Notably, the energy required for heating, cooling, and lighting and power generation efficiency of DSSCs can be influenced by the climate. Thus, four climate zones in the United States were considered to perform a comparative analysis. The total energy consumption of the buildings was analyzed using DesignBuilder, a computer simulation program, and three window types were compared: Low-E, DSSC-R, and DSSC-Y. In general, DSSCs consume a considerable amount of lighting energy because of their low visible light transmittance. To decrease the lighting energy consumption, three lighting control methods were consid-ered, and the corresponding total energy consumption was analyzed. The energy consumption can be minimized using the linear/off lighting control method. The energy consumption associated with Low-E can be further decreased by enhancing the power generation performance of the DSSCs. Specifically, when the power gener-ation efficiency of DSSC-R is more than 13%, the overall energy consumption is lower than that of Low-E in all climates. The presented findings can guide the development of power generation efficiency standards for DSSC BIPV windows.