Bifacial Color-Tunable Transparent Photovoltaics for Application as Building-Integrated Photovoltaics

Transparent photovoltaics (TPVs) have attracted enormous attention due to their potential to be applied as building-integrated photovoltaics (BIPV). Transparent and semitransparent photovoltaics have achieved a high level of efficiency, but there are still a number of issues that limit their application, such as their device size, lack of stability, and transmittance in the visible wavelength region. The excellent color implementation of a bifacial color-tunable (BCT) TPV by tuning the indium tin oxide (ITO) thickness is demonstrated. The BCT TPV has a bifacial factor of 97.2% while maintaining an average visible transmittance (AVT) of 41.6%. The use of a 16 cm² large-scale TPV device using a dry plasma fabrication process is also demonstrated. This dry process enables large-scale device production and ensures long-term device stability. The efficiency improvement with various background colors (blue 14%, red 25%, and white 35%) without any additional installation on the device is also confirmed. The BCT TPV is a promising candidate for BIPV applications due to its wide range of color tunability and excellent double-sided photovoltaic operation, even under an indoor artificial light.