International Journal of Energy Research, Vol.40, No.1, 13-29, 2016
Progress in carbon fuel cells for clean coal technology pipeline
As coal use for electricity production is expected to increase substantially in the next several decades, our carbon-constraint world demands sustainability, which requires urgent advances in coal power generation to achieve significantly reduced footprints on the environment, water resources, and climate change. Carbon fuel cells (CFC) that can electrochemically convert solid fuels directly into electricity hold the potential to leap-frog the technological evolution process towards achieving clean coal power generation by offering dramatically higher conversion efficiencies and proportionately lower carbon intensity, emissions, and water demand, while producing a highly concentrated CO2 flue stream that is nearly capture-ready. This article provides the prospects and overview of CFCs in the context of other advanced coal power generation technologies, and discusses both the status of research progress in this exciting and emerging technology, and also some of the challenges yet to overcome. Research up to date has demonstrated remarkable power densities up to nearly 900 mW/cm(2) for pyrolyzed carbon and 450 mW/cm(2) for untreated coal char. Also, conversion efficiencies around 50% were experimentally demonstrated for coal in a solid oxide-based CFC system, while calculations estimated an efficiency of 80% for converting pyrolytic carbon fuel in a molten carbonate-based CFC system. With such practically significant performance, figures coupled with potentially high conversion efficiencies and an impressive list of environmental merits, CFCs gain a rightful place in the clean coal power technology pipeline. Copyright (c) 2015 John Wiley & Sons, Ltd.
Keywords:clean coal;electricity generation;electrochemical conversion;carbon intensity;efficiency;carbon oxidation;carbon fuel cell;CO2 emission