316

20 Application of Sustainable Micro-Algal Species in the Production of Bioenergy

Bio fuels

Natural biofuel

firewood, plants, wood

chips, and forest animals

First generation (biofuel

produced from wheat,

barely, corn, and, potato)

Second generation (biodeisel

and bioethanol produced

from cassava jatropha)

Third generation (microalgae

and microbes)

Primary bio-fuels

Secondary bio-fuels

Figure 20.1

Classification of biofuels.

parts (potatoes, grains, and oilseeds, etc.) fall under the category of “first-generation

fuels,” which are also known as “conventional biofuels”; second generation of

biofuels are the fuels generated from nonedible plants and its components; lastly,

third generation of biofuels are produced from microalgae.

First- and second-generation biofuel resources include certain restrictions that

pose novel disputes on land usage for biomass resource production which would

contribute to the food crisis. Hence, the third-generation biofuels are consid-

ered as the most appropriate option, concerning economic and environmental

sustainability [1].

20.1.2

Microalgae and Bioenergy

The chapter gives an elaborate view of the highly promising bioenergy source –

microalgae. Algal biomass can be converted into biofuels like cellulosic ethanol and

biodiesel, for transportation. These fuels are functionally equivalent to petroleum

fuels and form the most appropriate alternative for conventional fuels. Microalgae

have got an extensive application and widely used as a feedstock for biofuel creation.

They can produce a valuable quantity of polysaccharides as well as triacylglycerides.

Microalgae additionally produce proteins which can be utilized as a source of food

[2]. The possibility for microalgae as an unlimited and practical feedstock for biofuel

manufacture has motivated a focus in the biorefinery. The modern advancement

of microalgae to deliver biofuel and bioproducts has expanded significantly in the

course of the most recent couple of decades [3]. Some of the microalgae species

used in the research for biomass generation are chlorophyceae, euglenophyceae,

prasinophyceae, haptophyceae, eustigmatophyceae, bacillariophyceae, cyclotella

cryptic, cyanobacteria, arthrospira (spirulina) platensis, etc [4].

Biofuel is a highly flexible bioenergy resource which can be turned positive and

downward rapidly to meet the fluctuating energy requirement. It forms a big encour-

agement for dependent renewable technologies like wind and solar energies. To

keep the energy supply clean and ethical, the bioenergy should meet the following

requirements: