A system including biogas purification and provides biogas as feedstock to a solid oxide fuel cell. The biogas purification treatment process provides a polished biogas that is substantially free of carbonyl sulfides and hydrogen sulfide. The system uses a biogas treatment apparatus, that includes apparatus such as a packed columns, comprising copper oxide or potassium permanganate packing material, and an activated carbon component configured to treat the biogas by polishing it to remove carbonyl sulfides and deleterious trace residues, such as hydrogen sulfide, that were not removed by any prior bulk H2S removal steps. In addition, an oil removal device is used to remove any entrained fine oil droplets in the biogas. A polished biogas having in the range of 60% methane is charged to the fuel cell. Electricity generated may be fed into a grid or used directly as energy to charge electrical-powered vehicles, for example. Energy credits are tracked in real time and are appropriately assigned.38
