open pond production (Wigmosta et al. (2011) and photobioreactor is required 1.853
 10
8 acres area in the CONUS plus Hawaii to produce 315 billion gallon/year
(BGY) of algal lipid production (Quinn et al. 2012). Topography and soil limit the
land availability for algae farming in open pond systems. Soils porosity and permeability affect the construction costs and design of open systems. Topography is the
limiting factor for open pond systems because the installation of large shallow ponds
requires relatively flat terrain. The bulk density of soil (quality indicator) below the
liners could influence the future productivity of the soil for the environmental
sustainability of algal biofuels. Biofuel production at coastal sites could also be
influenced by land prices and availability. Land desirable for development and for
publicly beneficial reasons may not be seen as suitable for biofuel production.
1.5.4 Nutrients
Availability and cost of nutrients (i.e., nitrogen, phosphorus, and potassium) play an
important role in commercial viability for algae growth (Venteris et al. 2014; Pate
2013; Williams and Laurens 2010). Pate (2013) has been estimated that 7 million
metric tons of nitrogen and 1.03 metric tons of phosphorus will be required for algal
biofuel production in range from 4.5 BGY to 12 BGY. The requirement of nutrient
determined by hydrothermal liquefaction with combined catalytic hydrothermal
gasification (CHG) has resulted in improvement on nitrogen (34%) and decrease
in phosphorus consumption (52%) as compared to another method of lipid extraction
(Venteris et al. 2014).
1.5.5 Carbon Dioxide
Atmospheric CO 2 is a limiting factor for efficient algal production due to slow
diffusion rates. Autotrophic microalgae cultivation scalability and operating expense
are influenced by CO 2 availability and cost of delivery. CO 2 waste gas could be used
a potential source for low-cost algal cultivation. Algae can use emitted CO 2 to
convert into organic molecules that can be used as biofuel, building blocks for the
biotechnology industry, and energy. Thus algae production could be efficiently used
to reduce fossil carbon emission. Algae production does not directly involve in fossil
carbon sequestration, rather provides carbon capture and reuse in the form of fuels
derived from the algal biomass. Mitigation of CO 2 emissions from large industrial
plants, including coal and natural gas combustion plants are already operated under
the research area of carbon capture and utilization as a climate change abatement
strategy (Rubin et al. 2005; Campbell et al. 2008).
Several studies have been focused on the availability of carbon dioxide from
stationary sources for algal cultivation (Pate et al. 2011; Quinn et al. 2012; Venteris
et al. 2014). Estimated 10 billion gallons of fuel could be produced using sufficient
CO 2 from stationary sources (Pate et al. 2011). This amount of fuel production
account to approx. 20% of the U.S. waste carbon emitted per year (Venteris et al.
1 Algal Biofuel: A Sustainable Approach for Fuel of Future Generation
17
 10
8 acres area in the CONUS plus Hawaii to produce 315 billion gallon/year
(BGY) of algal lipid production (Quinn et al. 2012). Topography and soil limit the
land availability for algae farming in open pond systems. Soils porosity and permeability affect the construction costs and design of open systems. Topography is the
limiting factor for open pond systems because the installation of large shallow ponds
requires relatively flat terrain. The bulk density of soil (quality indicator) below the
liners could influence the future productivity of the soil for the environmental
sustainability of algal biofuels. Biofuel production at coastal sites could also be
influenced by land prices and availability. Land desirable for development and for
publicly beneficial reasons may not be seen as suitable for biofuel production.
1.5.4 Nutrients
Availability and cost of nutrients (i.e., nitrogen, phosphorus, and potassium) play an
important role in commercial viability for algae growth (Venteris et al. 2014; Pate
2013; Williams and Laurens 2010). Pate (2013) has been estimated that 7 million
metric tons of nitrogen and 1.03 metric tons of phosphorus will be required for algal
biofuel production in range from 4.5 BGY to 12 BGY. The requirement of nutrient
determined by hydrothermal liquefaction with combined catalytic hydrothermal
gasification (CHG) has resulted in improvement on nitrogen (34%) and decrease
in phosphorus consumption (52%) as compared to another method of lipid extraction
(Venteris et al. 2014).
1.5.5 Carbon Dioxide
Atmospheric CO 2 is a limiting factor for efficient algal production due to slow
diffusion rates. Autotrophic microalgae cultivation scalability and operating expense
are influenced by CO 2 availability and cost of delivery. CO 2 waste gas could be used
a potential source for low-cost algal cultivation. Algae can use emitted CO 2 to
convert into organic molecules that can be used as biofuel, building blocks for the
biotechnology industry, and energy. Thus algae production could be efficiently used
to reduce fossil carbon emission. Algae production does not directly involve in fossil
carbon sequestration, rather provides carbon capture and reuse in the form of fuels
derived from the algal biomass. Mitigation of CO 2 emissions from large industrial
plants, including coal and natural gas combustion plants are already operated under
the research area of carbon capture and utilization as a climate change abatement
strategy (Rubin et al. 2005; Campbell et al. 2008).
Several studies have been focused on the availability of carbon dioxide from
stationary sources for algal cultivation (Pate et al. 2011; Quinn et al. 2012; Venteris
et al. 2014). Estimated 10 billion gallons of fuel could be produced using sufficient
CO 2 from stationary sources (Pate et al. 2011). This amount of fuel production
account to approx. 20% of the U.S. waste carbon emitted per year (Venteris et al.
1 Algal Biofuel: A Sustainable Approach for Fuel of Future Generation
17