**9. Techno-Economic Evaluation of Microbial Fuel Cell Technology**

Trapero et al. year evaluated the techno-economic status of MFC utilizing juice industry wastewater in an aerobic system [160] through modifications conducted in the parameters like utilization of a dual-chambered reactor with carbon cloth as an anode along with the two types of cathodes; Pt coated carbon cloth and non-Pt coated carbon cloth, both in comparison to the conventional process utilizing activated sludge. This configuration has an effluent flow rate of 54 m3/day with a COD of 15,000 mg/L. The removal of COD ranges from 40–90%, along with the Coulombic efficiency from 2–30% chosen for the technoeconomic assessment relying mostly on the power efficiency and wastewater treatment. The initial investment in consideration of MFCs, including electrodes, DC/AC converter, membranes, pumps, and the fan, is much greater than the conventional treatment plant, requiring just pump fans and a biological tank. Various other investments need to be estimated, such as the costs for operating the treatment plant of 100 m<sup>3</sup> of the volume, including the labor cost of 35%, which is around EUR 3248/year, 19% of the investment for management of the sludge costing EUR 1763/year along with 34% of the investment costing EUR 3155/year for electricity, indicating that most of the investment will be carried out for providing labor and electricity for the plant. In comparison to MFCs, the overall cost of the investment can be reduced because of the automation and no necessity for aeration at the wastewater treatment plant. Based on this estimation, the overall operating cost of MFC ranges around EUR 1700–2300/year, which is very low compared to the conventional process. However, this estimation can be considered only if there is no requirement of replacing the electrodes or membranes. Thus, the construction of highly durable MFC parts is essential for making the process economically viable. Therefore, it is a practical implementation because the capital cost is high compared to the operating cost, which is directly in contrast to the conventional treatment system. In a general scenario, at 30% Coulombic Efficiency, there is 90% efficient COD removal creates a relatively better cash flow than the conventional process (EUR 2600–3400/year) [161].
