Integrating enzyme fermentation in lignocellulosic ethanol production: life-cycle assessment and techno-economic analysis

Table 2 Sensitivity analysis of ethanol GHG emissions (expressed as GWP)

g CO₂-eq. MJ⁻¹ ethanol (LHV)	ISO					RED
g CO₂-eq. MJ⁻¹ ethanol (LHV)	Off-site	A	A+	B	B+	Off-site	A	A+	B	B+
Base case^a	50	24	23	23	22	31	16	16	15	15
SOC 2–3 rotations	78	53	52	51	50	47	33	32	31	31
SOC 1 rotation	111	89	86	85	84	66	53	52	50	50
SOC 20 years	700	710	700	670	670	500	510	500	480	480
Solid fuel substitutes coal	−21	−64	−62	−68	−64
Electricity substitutes natural gas-based electricity^b	44	24	22	20	18

Results with alternative data and assumptions regarding soil organic carbon (SOC) and substituted products
^aBase case includes only fossil GHG emissions, excluding changes in SOC levels
^bIn this scenario imported electricity in case A is also assumed to be natural gas-based

ISSN: 2731-3654