From eight to fifteen litres of liquid by-products are generated for every litres of grain whisky produced. 'Spent Wash' is the main liquid stream. If discharged untreated into the environment it might contribute to pollution such as eutrophication [1]. Microbial Fuel Cells (MFCs) are a natural bio-technology solution to the issue working either independently or in conjunction with established wastewater treatment technologies. Utilising metabolic reactions of electrochemically active microorganisms, MFCs provide a dual benefit: wastewater treatment and direct electricity generation. For industrial scale-up, the approach in this work is through plurality. Multiple units of relatively small scale can be connected electrically and hydraulically to achieve the necessary capacity [2]. Initially a single chamber open air cathode MFC of 170ml volume treating spent wash subsequent to anaerobic digestion treatment of 2g/l Chemical Oxygen Demand demonstrated an average voltage of 0.4V in open circuit and a COD reduction of 70%. Scaling up, two 100lt units connected in parallel and operating in directly diluted spent wash at 0.46g COD/l.d demonstrated 84% COD removal, maximum voltage 0.9V and current 160mA. Ongoing experiments using this configuration and previously anaerobically treated spent wash demonstrate encouraging results, bringing practical industrial scale Microbial Fuel Cell treatment closer. [1] Mohana, S; Acharya, K B; Madamwar, D., 2009. Distillery spent wash: Treatment technologies and potential applications. Journal of Hazardous Materials, Volume 163, pp. 12-25 [2] Gálvez, A., Greenman, J. & Ieropoulos, I., 2009. Landfill leachate treatment with microbial fuel cells; scale-up through plurality. Bioresource Technology, Issue 100, pp. 5085-509