Progress in energy from microalgae: A review

Microalgae have great potential as renewable fuel sources, but a dire need exists for high-level academic and industrial research into their growth and bioprocessing. New algae strains that efficiently use CO2 and wastes as nutrients, novel oil extraction methods, and industrial-scale designs for fuel production are imperative for long-term energy sustainability. A particular challenge to research in this field is the transition from pilot studies to industrial operations, which often exposes algae cells and their products to hostile environments, reducing yields. Hence, a need exists to integrate algae cell engineering with predictive bioprocess engineering to ensure economic and environmental feasibility and minimize the number of full-scale trials that fail. This review provides a brief overview of biofuel production from microalgal biomass. It highlights the most promising microalgae species for different types of fuel, the proper choice of photobioreactor and process parameters, product extraction techniques, and the main biofuel products. The main goal of this paper is to promote research into energetically- and environmentally-favorable technologies via the development of better algal strains and separation, extraction, and conversion methods.

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