Integrated biorefinery approach for sustainable biofuel production from algal biomass

Renewable alternative biofuels can solve two important current global challenges, i.e., energy crisis and global warming. Biofuels such as bioethanol, biodiesel, and biogas from algal biomass are alternative sources of renewable energy and have attracted considerable attention in recent years. However, the major problem with biofuel from algae is its high production cost. Therefore, to minimize the production cost of fuel, biorefinery approaches in which many value-added products with market potential are extracted from the algae along with biofuel was discussed. Bioremediation of wastewaters by different types of algae was integrated with biofuel production to make the biorefineries sustainable. The sustainability parameters such as techno-economic analysis and lifecycle assessment of different algal biorefineries considered indicates that a biorefinery with (a) advanced technology; (b) multiproduct production facility; (c) recycle/reuse of nutrients and/or catalyst; and (d) waste (flue gas, wastewater) usage have made algal cultivation more sustainable. In brief, sustainable biofuel production from algae through biorefinery approaches is possible and because of its application in wastewater remediation, CO₂ mitigation and clean energy and various by-products production, algae have the potential to achieve many sustainable developmental goals (SDGs), specifically SDG-6, 7, 11, 13, of the United Nations.