Life-cycle analysis of greenhouse gas emissions from renewable jet fuel production

Table 3 Allocation ratios for non-energy co-products and electricity [25, 29, 30, 56, 59–63]

Supply chain component	Applicable for pathway	Main product	Co-product	Co-product allocation ratio r_A Co-product/main product		Displaced product	Displacement ratio r_D	Emission factor	Reference
Supply chain component	Applicable for pathway	Main product	Co-product	MJ/MJ	g/MJ	Displaced product	g displaced product/g co-product	g CO_2eq/g displaced product	Reference
Non-energy co-products
Camelina oil extraction	HEFA	Camelina oil	Camelina meal	0.64	47.79	Soybean meal	0.77^a	0.53	[25, 59, 60]
Corn dry mill ethanol production w/o corn oil extraction^b	ATJ	Ethanol	Distillers grain solubles	0.68	31.74	Corn	0.78	0.29	[29]
						Soybean meal	0.31	0.53
						Urea	0.02	1.22
Corn dry mill ethanol production w/ corn oil extraction^b	ATJ	Ethanol	Distillers grain solubles	0.65	30.36	Corn	0.78	0.29	[29]
						Soybean meal	0.31	0.53
						Urea	0.02	1.22
		Ethanol	Corn oil	0.04	1.06	Soy oil	1.00	0.53	[29]
Corn wet mill ethanol production^b	ATJ	Ethanol	Corn gluten meal	0.15	6.87	Corn	1.53	0.29	[29]
		Ethanol	Corn gluten meal	0.15	6.87	Urea	0.02	1.22	[29]
		Ethanol	Corn gluten feed	0.56	29.74	Corn	1.00	0.29	[29]
		Ethanol	Corn gluten feed	0.56	29.74	Urea	0.02	1.22	[29]
		Ethanol	Corn oil	0.21	5.52	Soy oil	1.00	0.53	[29]

Supply chain component	Applicable for pathway	Main product	Co-product	Co-product allocation ratio r_A Co-product/main product	Displaced product	Displacement ratio r_D	Emission factor	Reference
Supply chain component	Applicable for pathway	Main product	Co-product	MJ/MJ	Displaced product	MJ displaced product/MJ co-product	g CO_2eq/MJ displaced product^c	Reference
Electricity (co-product)
FT synthesis	FT	RJF	Electricity	0.45	US grid electricity	1.00	137.88	[30]
Jatropha oil extraction	HEFA	Jatropha oil	Electricity^d	0.34	US grid electricity	1.00	137.88	[29]
Pyrolysis	Pyrolysis ex situ case	RJF	Electricity	0.51	US grid electricity	1.00	137.88	[54]
Ethanol from corn stover	ATJ	Ethanol	Electricity	0.10	US grid electricity	1.00	137.88	[61]
Ethanol from sugarcane	ATJ	Ethanol	Electricity	0.22	Brazilian grid electricity	1.00	26.52	[62]
Sugarcane milling	DSHC (increased blend level)	RJF	Electricity^e	0.13	Brazilian grid electricity	1.00	26.52	[63]
Sugarcane milling	DSHC (10% blend level)	RJF	Electricity^e	0.07	Brazilian grid electricity	1.00	26.52	[63]

^aBased on the ratio between the average protein content of camelina (36.2%) and soybean meal (47%)
^bGREET uses a weighted average of three different corn ethanol technologies. Dry mill ethanol production without corn oil extraction, dry mill ethanol production with corn oil extraction, and wet mill ethanol production respectively produce 18.23% , 72.91% and 8.87% of the total produced ethanol
^cFor electricity production, an average emission factor without transmission and distribution losses was used. For electricity consumption, these losses were included. For pathways located in Brazil, a much lower emission factor was used due to the high diffusion of hydropower in the electricity mix
^dFrom the combustion of jatropha husks, shells and meal
^eFrom the combustion of bagasse, after deduction of internal use of heat and power in the DSHC process

ISSN: 2731-3654