A mono-block-layer build type (MOLB-type) geometry, composed with trapezoidal cross-section channels for fuel and air, of solid oxide fuel cell (SOFC), is modeled in this study using a three dimensional computational fluid dynamics (CFD). The model is used to obtain the performance of the SOFC considering internal reforming of methane in the anode side with different biogas compositions. From the results obtained, a new configuration for the MOLB-type geometry is proposed. The model takes into account the mass transfer, heat transfer, species transport, chemical and electrochemical reactions, detailed comparisons of species concentration, temperature and electric fields inside the cell analyzed in the present study. Results show that the biogas from local sludge has the lower temperature gradient and more homogeneous current density distributions along of the fuel cell, on the other hand, with the new configuration proposed for the MOLB-type geometry the temperature distribution inside of the fuel cell has lower temperature gradients. (C) 2014 Elsevier Ltd. All rights reserved.