Transparent Backsheets for Bifacial Photovoltaic Modules

Bifacial modules now represent a growing percentage of the PV module market due to their higher output power and more effective use of the available light for photovoltaic conversion. Initial adoption of double glass module constructions has raised concerns related to increased module weight and potential failure mechanisms. The introduction of transparent backsheets has provided an alternative that brings advantages including lighter weight, established manufacturing processes and established field performance. In this paper we discuss the development of a transparent backsheet based on Tedlar (R) polyvinylfuoride films. The long-term durability of these transparent backsheets and the stability of key backsheet properties is reviewed. The performance of these backsheet in accelerated module testing is also discussed.