This study reports, for the first time in literature, the possibility of simultaneously producing H-2 and C-2s hydrocarbons by using an anionic single chamber solid electrolyte cell of Pt/YSZ/Ag (working/solid electrolyte/counter) tested under a humidified CH4 atmosphere (no direct O-2 feeding gas to the reactor). Hydrogen was mainly produced in the Pt working electrode under application of negative polarizations by a steam electrolysis process (H2O + 2e(-) -> H-2 + O2-). Simultaneously, the produced O2- ions were electrochemically pumped to the Ag counter electrode, leading to the production of C-2s hydrocarbons (ethane and ethylene), via oxidative coupling of CH4 (CH4 + O2- -> C2H4 + C2H6 + 2e(-)). The influence of the applied current, reaction temperature and feeding composition on the electrocatalytic performance of the cell was evaluated for both processes. It was found that the possibility of controlling the rate of O2- supply allows to control and optimize the production rate of the desired compounds (H-2 and C-2s) at varying the reaction conditions. In addition, the stability of the cell for long polarization times has been demonstrated under the optimal conditions for the production of both compounds. (C) 2011 Elsevier B.V. All rights reserved.