Biomass solid oxide fuel cell using solid weed waste as fuel
Takashi Hibino, Kazuyo Kobayashi, Takuma Hitomi
Abstract
Weed waste is an abundant and carbon-neutral feedstock for energy recovery. A potential approach to improve the efficiency of waste-to-energy conversion is the application of a fuel-cell-type reactor to the treatment system to generate electricity from the feedstock, with high power and energy density. Herein, we report a solid oxide fuel cell (SOFC) that directly uses solid weed waste as fuel. Grasses tested in this study were Miscanthus sinensis, Solidago canadensis, and Pueraria montana. The conversion reactions for these grasses, especially in situ gasification, were effectively catalyzed at 800 °C by a thin layer of a silver–iron(III) oxide mixture that was deposited onto the anode substrate. The use of Solidago canadensis and Pueraria montana provided the highest power density (0.41 W cm−2) and energy density (0.42 Wh g−1), respectively, which were closely related to their lignin and ash contents. Importantly, this SOFC exhibited good performance not only in batch mode but also in continuous free-fall mode.