Microalgae biofuels: A critical review of issues, problems and the way forward

Culturing of microalgae as an alternative feedstock for biofuel production has received a lot of attention in recent years 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. In addition, this superior feedstock offers several environmental benefits, such as effective land utilization, CO(2) sequestration, self-purification if coupled with wastewater treatment and does not trigger food versus fuel feud. Despite having all these 'theoretical' advantages, review on problems and issues related to energy balance in microalgae biofuel are not clearly addressed until now. Base on the maturity of current technology, the true potential of microalgae biofuel towards energy security and its feasibility for commercialization are still questionable. Thus, this review is aimed to depict the practical problems that are facing the microalgae biofuel industry, covering upstream to downstream activities by accessing the latest research reports and critical data analysis. Apart from that, several interlink solutions to the problems will be suggested with the purpose to bring current microalgae biofuel research into a new dimension and consequently, to revolutionize the entire microalgae biofuel industry towards long-term sustainability.