Biogas is one of the most interesting renewable sources and, in particular, landfill biogas, which has a low heating value, can be used in a solid oxide fuel cell (SOFC) in order to produce electricity, at higher efficiency with respect to internal combustion engine (ICE) or other types of fuel cell, and heat. An SOFC working with carbon-containing fuels needs a reforming agent, such as steam, carbon dioxide or oxygen, in order to avoid the carbon deposition, which leads to a fast degradation of the cell. Pre-mixed biogas, which consists in biogas with the same composition of the real one, but mixed directly through mass flow controller (MFC), in order not to have impurities, and real biogas, which needs a pre-cleaning, have been used.