Fig. 4: Techno-economic analysis and life cycle assessment under uncertainty and across the fermentation design and technological landscape.
Uncertainties (box and whisker plots) and breakdowns (stacked bar charts) for (A) minimum product selling price (MPSP) and (B) cradle-to-grave 100-year global warming potential (GWP100). Whiskers, boxes, and the middle line represent 5th/95th, 25th/75th, and 50th percentiles from 2000 Monte Carlo simulations (n = 2000 simulations) for each scenario. Pentagon, square, and diamond markers represent baseline results for the laboratory batch (Lab. batch) laboratory fed-batch (Lab. fed-batch), and pilot batch (Pilot batch) scenarios, respectively. Stacked bar charts report baseline results for the pilot batch scenario; results for other scenarios are included in the SI. Electricity consumption includes only the consumption of the system; production was excluded in the depicted breakdown for figure clarity. Tabulated breakdown data for material and installed equipment costs, heating and cooling duties, electricity usage, GWP100, and FEC are available online62. Labeled dark gray lines denote reported impacts for fossil-based production pathways (f152; f2-f451). Labeled light gray lines denote reported impacts for alternative bio-based production pathways (b151; b253; b352). Where GWP100 was reported as cradle-to-gate, 1.49 kg CO2-eq./kg was added as end-of-life impacts for consistency with this study and Dunn et al. 2015. Values for all reported MPSPs and impacts before and after adjustment are listed in Supplementary Table 3 and 4. (C, D) MPSP and (E, F) GWP100 across 2500 fermentation yield-titer combinations at the baseline productivity of the pilot batch scenario (0.66 g/L/h) for neutral (left panel; C, E) and low-pH (right panel; D, F) fermentation. Yield is shown as % of the theoretical maximum (%theoretical) scaled to the theoretical maximum yield of 1.31 g/g-glucose-equivalent (based on carbon balance). For a given point on the figure, the x-axis value represents the yield, the y-axis value represents the titer, and the color and contour lines represent the value of MPSP, GWP100. Diamond markers show baseline results for the pilot batch scenario. Source data are provided as a Source Data file.
