Greenhouse gas footprints of utility-scale photovoltaic facilities at the global scale

Abstract

Abstract Technological characteristics and meteorological conditions are major determinants of the greenhouse gas (GHG) footprints of photovoltaic facilities. By accounting for technological and meteorological differences, we quantified the GHG footprints of 9992 utility-scale photovoltaic facilities worldwide. We obtained a median greenhouse gas footprint of 58.7 g CO2-eq kWh−1, with a 3-fold spread (28.2–94.6 g CO2-eq kWh−1, 2.5th and 97.5th percentiles). Differences in panel type appeared to be the most important determinant of variability in the GHG footprint, followed by irradiation and a facility’s age. We also provided a meta-model based on these three predictors for users to determine the facility-specific greenhouse gas footprint. The total cumulative electricity produced by the utility-scale photovoltaic fleet worldwide is 457 TWh yr−1, 99.6% of which is produced at footprints below 100 g CO2-eq kWh−1. Compared to earlier studies, the footprints we computed of global utility-scale facilities show a relatively large spread. In order to further improve the accuracy of facility-specific footprints, more information on panel type as well as production country is required.