As reported on the PV Performance Modeling Collaborative (PVPMC), Sandia Labs is leading a three-year research project to study bifacial photovoltaic technology and performance. The project is sponsored by SunShot, a U.S. Department of Energy program. Conventional PV cells convert light hitting the front side of the cell to electricity. With a few extra processing steps, bifacial PV cells can be made so that light hitting from both sides contributes to the current produced by the cell. When cells are placed into modules designed with transparent back sheets or glass-glass construction, bifacial PV modules are born. This idea is not new, but this technology has, thus far, remained on the fringe of the PV market. We believe that bifacial PV may begin to enter the mainstream of the PV industry in the next few years, especially if its levelized cost of energy is lower than monofacial technologies. Field data, characterization methods and standards, and predictive models are needed.

As partners in this project, Sandia National Laboratories, the National Renewable Energy Laboratory, and the University of Iowa are working together to better understand the performance characteristics of bifacial PV modules and systems. This work is divided into the following tasks.

  1. Outdoor bifacial PV performance data
  2. Bifacial characterization and rating standards
  3. Performance modeling of bifacial PV systems