Operation of solid oxide fuel cell on biomass product gas with tar levels >10 g Nm−3

This work assesses experimentally the feasibility of feeding a high tar load product gas from biomass gasification to a planar solid oxide fuel cell (SOFC) for renewable electricity generation. The SOFC had a nickel gadolinium-doped ceria anode (Ni-GDC) and the gasifier was a pilot scale circulating fluidized bed, employing hot gas-cleaning to remove particulates, HCl and H2S. The SOFC operated for several hours on either pre-reformed gas (reduced tar levels < 0.5 g Nm−3) as well as on high tar-laden wood gas (tar levels > 10 g Nm−3) i.e. with no pre-reforming of tars. The tests were carried out at low fuel utilization Uf of around 20% at a current density j = 130 mA cm−2. In all cases stable continuous SOFC performance was established. Post experimental examination of the SOFC showed that the anode was not affected by carbon deposition or other impurity accumulation.