This document summarizes a study on the effect of chemical oxygen demand (COD) on power production in single-chamber microbial fuel cells (MFCs) using brewery wastewater. Three MFCs were fabricated with different wastewaters varying in COD. Results showed that open circuit voltage, power output, and coulombic efficiency increased with higher COD. The wastewater with the highest COD (Balance wastewater) produced the most power at 31.01 mW/cm2 and had the highest coulombic efficiency of 11.3%. This demonstrates that brewery wastewater has potential for electricity generation in MFCs.