List of Abbreviation
1G
first generation
2G
second generation
3G
third generation
4G
fourth generation
SPR
sweet potato residues
VHG
very high gravity fermentation
SHF
separate hydrolysis and fermentation
SHCF separate hydrolysis and co-fermentation
SSF
simultaneous saccharification and fermentation
7.1
Introduction
Presently environmental and energy security concern are synergistically associated
two important factors controlling the sustainable growth of the human being all over
the world. With rapid industrialization, the dependence on fossil fuels has increased.
These fossil fuels helped in meeting the global energy need, but at the same time, it
has been contributing to pollution and global warming through greenhouse gas
(GHG) emissions (Vanhala et al. 2016). In addition to this, the fossil fuels (nonrenewable) reservoirs are also depleting, and at the current rate of consumption, it’s
expected to end by the next 40–50 years (Chen et al. 2016). With these concerns in
mind, different stakeholders working in the area of energy generation and environmental pollution have suggested different approaches such as the use of renewable
resources, i.e., solar, wind, tidal, and biomass-based energy generation approach.
Among these methods, solar, wind, and tidal are being exploited; however, huge cost
and land involved for these techniques and also changing environmental patterns
have limited their application. Therefore, biomass-based bioenergy especially
bioethanol is a cost-effective and eco-friendly alternative to fossil fuel (Balat
2009; Demirbas 2009). In an attempt to minimize the dependence on fossil fuel,
several developed countries, e.g., the USA, China, Brazil, and Canada, and several
EU nations have made substantial progress in bioethanol production. Developing
nations such as India have also made a substantial stride in the area of bioethanol
generation. Although gasoline gives 44% better energy yield as compared to ethanol,
it has certain disadvantageous properties as mentioned in Table 7.1.
There are different feedstocks used for bioethanol production, and its composition determines the overall yield and process cost involved. The other aspects
associated with the feedstock are its
availability, transportation, and their efficiency as alternatives to fossil fuels.
Based on the above parameters, various literature surveys suggest that a wide
range of biomass have been used by different research groups. Biofuels can be
divided into different generations, i.e., first, second, third, and fourth generations on
156
B. Kumar et al.
1G
first generation
2G
second generation
3G
third generation
4G
fourth generation
SPR
sweet potato residues
VHG
very high gravity fermentation
SHF
separate hydrolysis and fermentation
SHCF separate hydrolysis and co-fermentation
SSF
simultaneous saccharification and fermentation
7.1
Introduction
Presently environmental and energy security concern are synergistically associated
two important factors controlling the sustainable growth of the human being all over
the world. With rapid industrialization, the dependence on fossil fuels has increased.
These fossil fuels helped in meeting the global energy need, but at the same time, it
has been contributing to pollution and global warming through greenhouse gas
(GHG) emissions (Vanhala et al. 2016). In addition to this, the fossil fuels (nonrenewable) reservoirs are also depleting, and at the current rate of consumption, it’s
expected to end by the next 40–50 years (Chen et al. 2016). With these concerns in
mind, different stakeholders working in the area of energy generation and environmental pollution have suggested different approaches such as the use of renewable
resources, i.e., solar, wind, tidal, and biomass-based energy generation approach.
Among these methods, solar, wind, and tidal are being exploited; however, huge cost
and land involved for these techniques and also changing environmental patterns
have limited their application. Therefore, biomass-based bioenergy especially
bioethanol is a cost-effective and eco-friendly alternative to fossil fuel (Balat
2009; Demirbas 2009). In an attempt to minimize the dependence on fossil fuel,
several developed countries, e.g., the USA, China, Brazil, and Canada, and several
EU nations have made substantial progress in bioethanol production. Developing
nations such as India have also made a substantial stride in the area of bioethanol
generation. Although gasoline gives 44% better energy yield as compared to ethanol,
it has certain disadvantageous properties as mentioned in Table 7.1.
There are different feedstocks used for bioethanol production, and its composition determines the overall yield and process cost involved. The other aspects
associated with the feedstock are its
availability, transportation, and their efficiency as alternatives to fossil fuels.
Based on the above parameters, various literature surveys suggest that a wide
range of biomass have been used by different research groups. Biofuels can be
divided into different generations, i.e., first, second, third, and fourth generations on
156
B. Kumar et al.