In spite of its advantages, the main challenge observed with fermentative H2 production processes is the relatively low energy conversion efficiency from the organic source. Typical H2 yields range from 1 to 2 mol of H2/mol of glucose, which results in 80-90% of the initial COD remaining in the wastewater in the form of various volatile organic acids (VFAs) and solvents, such as acetic acid, propionic acid, butyric acid, and ethanol. Even under optimal conditions about 60-70% of the original organic matter remains in solution. Bioaugmentation with selectively enriched acidogenic consortia to enhance H2 production was also reported (Venkata Mohan, "et al.", 2007b). Generation and accumulation of soluble acid metabolites causes a sharp drop in the system pH and inhibits the H2 production process. Usage of unutilized carbon sources present in acidogenic process for additional biogas production sustains the practical applicability of the process. One way to utilize/recover the remaining organic matter in a usable form is to produce additional H2 by terminal integration of photo-fermentative processes of H2 production (Venkata Mohan, "et al." 2008e, Rai et al. 2012) and methane by integrating acidogenic processes to terminal methanogenic processes.