In this paper solid oxide fuel cells operating with dry synthetic biogas have been examined. In order to increase their stability the layers of CuO-CeO2, Cu1.3Mn1.7O4 and Y0.08Sr0.92Ti0.8Fe0.2O3-delta have been deposited on the Ni-YSZ anode site. These layers should catalyze the internal biogas reforming and prevent the carbon deposition on the anode site. It has been found that CuO-CeO2 and Cu1.3Mn1.7O4 catalysts led to an increase of the stability (at least 7 days) of the fabricated fuel cells powered by biogas, whereas the unmodified fuel cell, as well as the fuel cell with Y0.08Sr0.92Ti0.8Fe0.2O3-delta catalyst degraded gradually with time. A significant amount of carbon nanofibers has been formed on the catalyst surface after fuel cell test. However, they have not formed in the anode area. The use of CuO-CeO2 and Cu1.3Mn1.7O4 catalysts prevented the carbon deposition on the anode site, and thus the fuel cell degradation was slower when operating with biogas fuel. (C) 2014 Elsevier B.V. All rights reserved.