*4.6. Plant and Yard Waste*

Plant and yard waste residue contain a relatively high concentration of cellulose, hemicellulose, and lignin. This can undergo hydrolysis by providing a pretreatment step to make it easily biodegradable during microbial oxidation in MFCs. When a hydrolysate was generated from plant and yard waste, an energy output of 1.02 W/m<sup>2</sup> with COD removal efficiency of 76% and CE of 69% was recorded using an air cathode MFC [100]. Some aquatic plants have been demonstrated to have similar attributes to those observed for generic plant and yard waste hydrolysates with *Canna indica* (Canna)—rich in cellulose and hemicellulose. Lignin is observed to be suitable to generate a hydrolysate with a consortium maintenance capability. For the use of hydrolysates from these plant- and yard-based hydrolysates using an air cathode MFC, about 0.45 W/m<sup>3</sup> of volumetric power density can be generated [101].
