The LCA was performed following the same procedure used in our previous study. Briefly, the system boundary extends from cradle to biorefinery-gate for the operational phase and does not include the construction phase of the biorefinery. All operational inventory data originated from the biorefinery models leveraged in this study (Table ; SI). Life cycle inventory data for each raw material and ancillary input were adapted from the GREET 2020 model and the ecoinvent 3.7 life cycle inventory database. The life cycle impact assessment methodology used was the Intergovernmental Panel on Climate Change (IPCC) 2013, with a focus on GWP100 as the primary indicator (reported herein as carbon intensity). Three different allocation methods were employed to compare carbon intensity across biorefinery configurations: displacement, economic, and energy allocation (a detailed breakdown of the LCA results using each allocation method is provided in Section S4 of the SI). Because the biorefinery configurations presented here mainly produce biofuel, we focus our discussion on results using energy-based allocation of carbon intensity. The only co-product with alternative end uses is crude glycerol. While crude glycerol is produced in significant quantities, the choice of allocation factor under either economic or energy allocation (minimally 1.18% and maximally 4.53%; Tables and) does not change the conclusions of this study (Figures , and D; SI), in agreement with the low energy content (12 MJ•kg -1 ) and low price (0.1 USD•kg - 1 ) 23 of crude glycerol as compared to biodiesel (37 MJ•kg -1 and 0.50 USD•kg -1 , minimally).