Challenges in Microbial Fuel Cell and Future Scope

The imminent energy crisis due to reserved fossil fuel and global warming due to greenhouse gas emission warrant the necessity for environmentally friendly sources of energy. Fossil fuels adversely affect the nature due to the release of CO2 into the environment (Venkata Mohan et al. 2011; Venkateswar Reddy et al. 2011a; Kadier et al. 2016a, b). Hence the consumption of fossil fuels based energy sources has harshly threatened human life through its drastic consequences, such as global warming and environmental pollution. As a result, in the present global energy scenario, searching for other energy resources is necessary (Kadier et al. 2015; Chandrasekhar et al. 2015a; Venkata Mohan and Pandey 2013). Last few years, several researchers around the world have made remarkable efforts to find a solution for this energy crisis (Venkata Mohan et al. 2013). In this scenario, fuel cells are a unique addition to the list of alternative energy sources having a negligible CO2 emission. Production of electricity using microorganisms was firstly reported early in the last century (Potter 1911). Microbial fuel cell (MFC) have been considered as a bio-based reactor that modifies the chemical energy of substrate into electrical energy through biocatalytic action of exoelectrogenic microorganisms under anaerobic circumstances over sequences of metabolic reactions (Kondaveeti and Min 2015; Chandrasekhar et al. 2015b). MFC technology signifies an innovative approach of using microorganisms for bioelectricity generation by the oxidation of organic substrate varied from the synthetic substrate such as acetate, glucose to a complex mixture of the organic substrate including food, dairy, distillery, animal and domestic wastewater. In recent years, MFC technology has been developing as one of the popular wastewater treatment based technology to deliver clean water and green energy (Venkata Mohan and Chandrasekhar 2011a, b; Pant et al. 2012; Pandit et al. 2012a, b; Chandrasekhar et al. 2015b). These MFCs overtook other conventional technologies such as an aerated lagoon and anaerobic digester (Logan 2008). Unlike traditional fuel cells, one step conversion of carbon-rich organic waste as a potential substrate to generate bioelectricity in MFCs ensures better conversion capability. MFCs can evade extra gas treatment process due to its CO2 rich off-gas. Moreover, single chambered or open-air cathode MFCs do not need any external energy input. Hence, it can be advantageous for extensive application in locations lacking electrical amenities (Stams et al. 2006). This chapter stretches an account of the basic principles involved in the working of MFCs and the key applications, challenges and future scope of MFC technology, as it stands today.