Life cycle assessment of novel two-terminal (2T) and four-terminal (4T) perovskite/CIGS solar cells

Abstract

Perovskite solar cells are an emerging photovoltaic technology promising higher efficiency than monocrystalline silicon solar cells. This study assesses the environmental impacts of novel two-terminal (2T) and four-terminal (4T) perovskite/copper indium gallium selenide (CIGS) tandem solar cells at technology readiness levels (TRL) 3 (2T configuration) and 4 (4T configuration). Based on the life cycle assessment (LCA) methodology, impacts are assessed from cradle to gate, focusing on climate change impacts per 1 m2 of solar cell, 1 kWp of module capacity, and the environmental 1 kWh of produced energy. Other relevant environmental impact categories, cumulative energy demand (CED) and energy payback time (EPBT), are also considered. The impacts of critical parameters are a sensitivity analysis. The LCA results indicate global warming impacts (GWI) of 49 and 50 kg CO2eq/m2, 170 and 174 kg CO2eq/kWp for the 2T and 4T configurations, respectively. For both configurations, the GWI ranges from 3.2 to 5.6 gCO2eq/kWh. Prospective investigated in climate change impact assessments suggest that manufacturing impacts may increase by 4% by 2050 without climate policies because of changes in the European energy mix. Conversely, stringent climate policies could reduce climate change impacts by 77%. The sensitivity analyses identify electricity use as the most critical factor for climate change impacts. CED values are 1219 and 1266 MJ/m2 for the 2T and 4T configurations, respectively. For impacts per energy output, the CED is 4231 and 4380 MJ/kWp for the 2T and 4T configurations, respectively. For both configurations, the CED ranges from 80 to 140 kJ/kWh. The average EPBT values are 0.74 and 0.76 years for the 2T and 4T configurations, respectively.