9.1 Biofuels
Energy plays a central role in the improvement of technology and quality of life. In
recent years, many countries have turned to alternative energy sources due to the
limited reserves of fossil fuels and their negative effects such as increased greenhouse gases, global warming, unsustainability, and high prices. All these drawbacks
of fossil fuels (coal, petroleum, and gas) have increased the attention for sustainable,
renewable, economic, and alternative fuel sources like bioethanol, biodiesel, and
biohydrogen that are being produced from low-cost biomass (Mood et al. 2013;
Leong et al. 2018; Amoozegar et al. 2019).
According to Prasad and coworkers, population growth in the last 25 years has
increased the total energy consumption by approximately 200% (Prasad et al. 2019).
Factors such as the increase in global population, global warming, depletion of fossil
fuels, and a rise in demand for energy have led to the search for cost-effective and
renewable alternative energy sources (Das et al. 2015). Some advantages and
disadvantages arising from the use of biofuels can be seen in Fig. 9.1 (Leong et al.
2018; Prasad et al. 2019; Zabed et al. 2019).
In addition, the need and demand for sustainable energy sources have increased
due to industrialization, urbanization, globalization, and economic development
(Bhatia et al. 2017; Leong et al. 2018). Therefore, immediate measures should be
taken worldwide such as lowering greenhouse gas emissions, decreasing environmental problems, and increasing the quality of life (Hajjari et al. 2017; Majidian
et al. 2018; Prasad et al. 2019).
Reduction in fossil resources, increasing environmental problems, and global
warming are serious troubles that concern all communities. For this purpose, environmentally friendly, renewable alternative fuels and energy sources are being
developed in order to avoid the threat of such problems (Kardooni et al. 2018). In
this context, interest in the transformation of biomass into biofuels is rising (Pimentel
et al. 2009).
The excessive use of fossil fuels causes a large-scale imbalance in the global
energy need and leads to the search for alternative sources to meet the energy
needed. Furthermore, as a result of the burning of fossil fuels, the CO 2 level rises
in the atmosphere, which is one of the biggest factors of global warming. In order to
deal with such negative situations, there is a need for clean energy infrastructures
that are readily accessible, renewable, and greener for nature (Corral Bobadilla et al.
2017; Leong et al. 2018). Although fossil fuels are currently our main energy
sources, biofuels with renewable energy sources have also gained more attention
recently and replaced fossil fuels (Majidian et al. 2018). Since they are obtained from
biological material, biofuels are preferred as suitable alternative energy sources that
can be preferred against the disadvantages of fossil fuels (Bhatia et al. 2017).
Conversion of raw materials to biofuels by microorganisms has been a highly
effective, cost-effective, and interesting method in recent years (Barnard et al. 2010).
Using microorganisms in biofuel production stages is an important factor that
reduces costs. In addition to the contribution of microorganisms to biofuel
258
T. Karaytuğ et al.
Energy plays a central role in the improvement of technology and quality of life. In
recent years, many countries have turned to alternative energy sources due to the
limited reserves of fossil fuels and their negative effects such as increased greenhouse gases, global warming, unsustainability, and high prices. All these drawbacks
of fossil fuels (coal, petroleum, and gas) have increased the attention for sustainable,
renewable, economic, and alternative fuel sources like bioethanol, biodiesel, and
biohydrogen that are being produced from low-cost biomass (Mood et al. 2013;
Leong et al. 2018; Amoozegar et al. 2019).
According to Prasad and coworkers, population growth in the last 25 years has
increased the total energy consumption by approximately 200% (Prasad et al. 2019).
Factors such as the increase in global population, global warming, depletion of fossil
fuels, and a rise in demand for energy have led to the search for cost-effective and
renewable alternative energy sources (Das et al. 2015). Some advantages and
disadvantages arising from the use of biofuels can be seen in Fig. 9.1 (Leong et al.
2018; Prasad et al. 2019; Zabed et al. 2019).
In addition, the need and demand for sustainable energy sources have increased
due to industrialization, urbanization, globalization, and economic development
(Bhatia et al. 2017; Leong et al. 2018). Therefore, immediate measures should be
taken worldwide such as lowering greenhouse gas emissions, decreasing environmental problems, and increasing the quality of life (Hajjari et al. 2017; Majidian
et al. 2018; Prasad et al. 2019).
Reduction in fossil resources, increasing environmental problems, and global
warming are serious troubles that concern all communities. For this purpose, environmentally friendly, renewable alternative fuels and energy sources are being
developed in order to avoid the threat of such problems (Kardooni et al. 2018). In
this context, interest in the transformation of biomass into biofuels is rising (Pimentel
et al. 2009).
The excessive use of fossil fuels causes a large-scale imbalance in the global
energy need and leads to the search for alternative sources to meet the energy
needed. Furthermore, as a result of the burning of fossil fuels, the CO 2 level rises
in the atmosphere, which is one of the biggest factors of global warming. In order to
deal with such negative situations, there is a need for clean energy infrastructures
that are readily accessible, renewable, and greener for nature (Corral Bobadilla et al.
2017; Leong et al. 2018). Although fossil fuels are currently our main energy
sources, biofuels with renewable energy sources have also gained more attention
recently and replaced fossil fuels (Majidian et al. 2018). Since they are obtained from
biological material, biofuels are preferred as suitable alternative energy sources that
can be preferred against the disadvantages of fossil fuels (Bhatia et al. 2017).
Conversion of raw materials to biofuels by microorganisms has been a highly
effective, cost-effective, and interesting method in recent years (Barnard et al. 2010).
Using microorganisms in biofuel production stages is an important factor that
reduces costs. In addition to the contribution of microorganisms to biofuel
258
T. Karaytuğ et al.