Electrical energy produced by microbial fuel cells using wastewater to power a network of smart sensors

Abstract The value chain associated with wastewater treatment is discussed in this chapter. Using biological reactors like microbial fuel cells (MFCs), it is possible to understand that energy production can be associated with the conversion of organic matter present in wastewater. After a general operating principle introduction, which describes in detail the energy conversion performed by the bacteria, special attention is paid to the behavior of the MFC when subjected to different values of electrical charge by plotting its polarization curves. Three mechanisms are discussed to increase the extraction of energy from the MFC: increasing the size of the reactor; reactor serial and parallel association; and continuous and intermittent reactor operation. An electronic controller is described so that the energy produced can be used to harvest the energy necessary for the operation of a smart sensor.