Role of Microalgae in Microbial Fuel Cell

The reliance on conventional fossil fuels has resulted in the imminent energy catastrophe with the combined challenge of global warming and the depletion of these energy reserves (Nayak BK, Pandit S, Das D, Biohydrogen. In: Kennes C, Veiga ría C (eds) Air pollution prevention and control, Chapter 15, Wiley, pp 345–381, 2013). Our earth today is facing many environmental problems, ranging from pollution, global warming due to the accumulation of CO₂ in the atmosphere, depletion of natural energy sources like coal and petroleum and the increasing need for sustainable energy sources (Bentley, Energy Policy, 30(3):189–205, 2002). Research on renewable methods for producing energy has received utmost attention in last few years. Standing in such a situation, the use of microalgae to convert CO₂ into potential biomass coupled with their ability to produce oxygen gas, assumes strategic importance (Popp et al, Renew Sustain Energy Rev 32:559–578, 2014). Significant research is being carried out in this field to exploit this ability of microalgae and integrate it with microbial fuel cells. This integration becomes especially favourable considering the fact that the phototrophic organisms act as in-situ generators of oxygen which facilitate the reaction in cathode chamber of the MFC. Further, microalgae also effectively removes phosphorous and nitrogen from the wastewater which might not be possible solely by the MFCs (Rozendal et al, Trends Biotechnol, 26(8):450–459, 2008). The use of phototrophic organisms in MFCs leads to the development of photosynthetic microbial fuel cells or PMFCs (Rosenbaum et al, Curr Opin Biotechnol, 21(3):259–264, 2010).