Operation of anode-supported solid oxide fuel cells (SOFCs) on propane-air fuel mixtures was studied. A thermodynamic calculation was used to show that propane is partially oxidized without coking for oxygen-to-propane ratios > 1.75 and T > 733degreesC. Differentially-pumped mass spectrometer measurements verified partial oxidation at the anode under these conditions with H-2 as the primary product. In single-cell tests, stable output power density of 0.7 W/cm(2) was obtained without coking at 790degreesC with an oxygen-to-propane ratio of 1.75. Limiting current behavior was observed due to the diluted hydrogen produced by the partial oxidation. (C) 2003 Published by Elsevier B.V.