Life Cycle Assessment of Perovskite/Silicon Tandem Solar Cells Coupled with Solar Flow Battery Systems

The intermittent nature of solar energy has made it necessary for photovoltaic (PV) systems to rely on external energy storage when deployed off-the-grid. In recent years, solar flow batteries (SFBs) have emerged as a potential alternative, which integrates energy production and storage in an integrated device. Here we performed an environmental assessment by highlighting potential hotspots that might hinder their acceptance, offering less pollutive alternatives. Specifically, we analyzed the environmental impacts of perovskite/silicon tandem based SFB. Our results show that the PV cell is responsible for three fourths of the impact of the device at lab scale, while the stack frame is responsible for the remaining impact. At this scale, the impact of the electrolytes is negligible. We expect the impact of the frame to reduce as the scale increases, while we anticipate an increase for the importance of the electrolytes as more energy is stored. For the future, the impact of the PV cell could be reduced by using a back electrode different than gold, and by substituting the perovskite/silicon tandem configuration with a perovskite/perovskite one.