In this paper, the performance of a robust SO2 depolarized electrolyser (SDE) stack that involves neither Pt catalyst nor carbon compounds at ambient conditions is demonstrated. In particular, the effect of different anolyte flow configurations to the overall H-2 production rate and SO2 carry-over phenomenon is presented. These results indicate that serpentine anolyte flow (U-configuration) provides higher SO2 conversion, however, results in a more severe SO2 carry-over phenomenon due to increased membrane-electrolyte interface. In addition, individual unit cells in the stacks are monitored for further understanding about the different operational environment in each cell and to provide guidelines for future SDE stack design. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.