Systematic analysis of biomass derived fuels for fuel cells

As the demand for energy continuously increases, alternatives to fossil resources must be found to both prevent fossil source depletion and decrease overall environmental impact. One solution is increasing contributions from renewable, biological feedstock, and from wastes. This paper presents an analysis of the current methods of biomass conversion, to extract biofuels and biologically produced gases to then be used in fuel cells. Pathways for converting biomass feedstock into fuel cell fuels selected here were anaerobic digestion, metabolic processing, fermentation, gasification, and supercritical water gasification, which were compared to natural gas and fossil hydrogen reference cases. These thermochemical and biological conversion pathways can also make use of residues from agriculture, forestry, or some household and industry wastes, producing hydrogen and hydrogen-rich gases. Solid oxide fuel cells were also found to be the preferred technology for such bio-derived fuel gases, due to their wide range of fuel options, wide scalability from single kW to multi 100 kW, and high efficiency.