Third-Generation Biofuel: Algal Biofuels as a Sustainable Energy Source

Abstract

Algal biofuels are third-generation biofuels which do not require agricultural land and potable water resources. Recently, culturing of microalgae as an alternative feedstock for biofuel production has received a lot of attention due to their fast growth rate and ability to accumulate high quantity of lipid and carbohydrate inside their cells for biodiesel and bioethanol production, respectively. Algae can grow in brackish, marine, and wastewater mostly unsuitable for cultivating of all of the traditional crops and a variety of climatic conditions. It can also grow in municipal, animal, and even industrial runoff and help in their purification. Autotrophic algae grow through photosynthesis – by converting plentiful available sunlight, CO2, and available nutrients, including nitrogen, potash and phosphorous, magnesium, iron, calcium, and sodium into the vital biomaterial known as the green biomass. Most algae can grow or can be made to grow in the dark using fermentable simple sugars and the complex starch as “heterotrophic” growth or even in combine of both growth modes through the process called the “mixotrophic” growth. Attempts are made in this review to list some of the recent advances on algal biofuel production theory and practice citing various examples of establishments. The authors acknowledge the works of various companies cited in his paper with purely academic intention of providing wider perspective to readers.