World Energy Resources | 2016

WORLD ENERGY COUNCIL | WASTE-TO-ENERGY
LFG energy users, sustainable management of landfills, local air quality improvement and
job creation.
Microbial Fuel Cell (MFC)
MFCs are biochemical-catalysed systems in which electricity is produced by oxidising
biodegradable organic matters in the presence of either bacteria or enzyme 27 . Bacteria are
more likely to be used in MFCs for electricity production, which also accomplish the
biodegradation of organic matters and wastes. Good sources of microorganisms include
marine sediment, soil, wastewater, fresh water sediment and activated sludge. MFCs
consist of anodic and cathodic chambers separated by a proton exchange membrane. The
anodic part is usually maintained in the absence of oxygen, while the cathodic can be
exposed to air or submerged in aerobic solutions. Electrons flow from the anode to the
cathode through an external circuit that usually contains a resistor, a battery to be charged
or some other electrical device. Figure 5 below shows a typical two-chamber MFC 28 .
FIGURE 5: ILLUSTRATION OF A TYPICAL TWO-CHAMBER MICROBIAL FUEL
CELL
Source: Rahimnejada, M. et al. (2015)
The activity in a MFC consists of microbes that oxidise substrates in the anodic chamber,
releasing CO2 and producing electrons and protons in the process. The electrons are
27
Rahimnejad et al. (2011)
28
Reddy et al. (2010)
21