Energy and Environmental Performance of Bioethanol from Different Lignocelluloses

Table 6

Net energy summary including coproducts, no allocation.

Feedstock		Energy use (MJ/L^a)
		Agriculture	Biorefinery	Total input	Ethanol^b	Coproducts in agriculture^c	Coproducts in bioreinery^d	Total output	Net energy value (NEV)
Stover	Luo et al. [5]	10.0	0.5	10.5	21.2	85.2	0.2	106.6	96.1
Corn	Patzek [56]	9.9	17.0	26.9	21.2	25.9	4.1	51.2	24.3
	Pimentel and Patzek [7]	10.0	17.0	27.0	21.2	25.9	1.9	49.0	22.0
	Shapouri and McAloon [30]	5.3	15.2	20.5	21.2	24.0	7.3	52.5	32.0
	Graboski [29]	5.6	16.6	22.2	21.2	24.6	4.1	49.9	27.7
	Diaz de Oliveira et al. [28]	6.3	14.1	20.4	21.2	24.6	4.1	49.9	29.5
	Wu et al. [9]	6.6	12.5	19.1	21.2	24.6	4.0	49.8	30.7
Switchgrass	Wu et al. [9]	2.4	1.0	3.4	21.2	0.0	4.8	26.0	22.6
Sugarcane	Hadzhiyska et al. (base case) [32]	6.5	0.1	6.6	21.2	0.0	32.7	53.9	47.3
	Hadzhiyska et al. (future case) [32]	2.7	0.5	3.2	21.2	0.0	12.6	33.8	30.6
	Pimentel and Patzek [57]	2.6	3.4	6.0	21.2	0.0	0.0	21.2	15.2
	Diaz de Oliveira et al. [28]	5.6	0.6	6.2	21.2	0.0	1.1	22.3	16.1
	Macedo et al. [36]	2.0	0.3	2.3	21.2	0.0	3.0	24.2	21.9

^aThe unit of energy use is MJ per litre of ethanol produced from biorefinery.
^bNormalized energy value for ethanol based on lower heating value (LHV).
^cIn stover-ethanol study it refers to the corn as a coproduct in the agriculture; in the other six studies on corn-ethanol it refers to the harvested stover (60%, dry mass basis) as a coproduct, and the values are estimated in this study.
^dIn stover-ethanol and switchgrass-ethanol study it refers to electricity; in corn-ethanol studies it refers to a range of products from corn milling, such as dried distiller grains, corn gluten feed, and corn oil; in sugarcane-ethanol study it refers to electricity surplus or/and bagasse.