This paper presents a systematic study of a direct-flame solid oxide fuel cell (DF-SOFC) operating on methanol and ethanol flames by SEM, EIS, I-V polarization and mass spectrometer (MS) characterizations and numerical simulation. The experimental study demonstrated that, by adopting a conventional Ni + Sm(0.2)Ce(0.8)O(1.9) (SDC) anode, irreversible carbon deposition and a drop of cell performance was observed when running the cell on an ethanol flame, while no carbon was deposited by operating on a methanol flame. Fuel cell stability tests indicated significant degradation in performance after 3 h of operation on an ethanol flame, while no degradation was observed after 30 h of operation on a methanol flame. A simple qualitative explanation of the difference observed in the electrochemical performance for the fuel cell operating on a methanol flame and an ethanol flame is presented based on numerical simulation. (C) 2010 Published by Elsevier Ltd on behalf of Professor T. Nejat Veziroglu.