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This study analyzes the carbon footprint of an internal combustion engine scooter (ICE) and there are four types of electric scooters studied, namely: a hydrogen fueled scooter with on-board methanol steam reforming (on-board SMR), hydrogen scooter with methane steam reforming (SMR), plug-in electric scooter (PEV), and hybrid scooter. This paper also uses a sensitivity analysis to examine how the variations in fuel prices influence the cost-benefit of using a hydrogen scooter. The research results are as follows: (1) SMR and on-board SMR have the smallest carbon (0.0115 kg CO 2,e & 0.0117 kg CO 2,e ), PEV (0.0189 kg CO 2,e ), hybrid scooter (0.0614 kg CO 2,e ) and ICE (0.1378 kg CO 2,e ); the percentage of carbon emissions relative to ICE by each scooter are, in ascending order, 8%, 8%, 14% and 45%; (2) according to the ISO14067 standard, capital goods (fixed costs) cannot be accounted into total life cycle costs, and total life cycle costs excluding fixed costs are in descending order, SMR ($6632), ICE ($4233), on-board SMR ($3643), hybrid scooter ($3368) and PEV ($2824); (3) the variation of fuel price is the key factor of using hydrogen scooters. [ABSTRACT FROM AUTHOR]

Abstract: A porous medium-catalyst hybrid reformer for CO2 conversion by dry auto-thermal reforming (DATR) was investigated in this study, and its operating range was discovered. The hybrid design was used to enhance the oxidative heat release by internal heat recirculation during exothermic reaction conditions, thereby increasing the CO2 conversion efficiency. The experimental results show that the CO2 conversion could be enhanced with higher catalyst inlet temperatures. The examination of the operating range of DATR showed that the CO2 conversion efficiency increased at higher reaction temperatures and CO2/CH4 ratios (≧1). Moreover, DATR in high temperature conditions must be carried out with high O2/CH4 ratios. Under these conditions of high oxygen content, CO2 generation and reduction reactions occur simultaneously. Overall, optimal CO2 conversion can be obtained with an O2/CO2 ratio of approximately 0.5. At these conditions, CO2 conversion efficiency can reach approximately 13% without external heat addition. [Copyright &y& Elsevier]

This paper investigated the design of a porous medium–catalyst hybrid reformer for CO 2 conversion by dry auto-thermal reforming, with emphasis on the reaction temperature distribution. In the reforming process, the reaction under excess enthalpy was explored by interface temperature measurement and infrared thermograph observation in a porous medium assisted packed-bed catalyst reactor. The hybrid design was arranged with the catalytic packed-bed in the downstream of the porous medium. In the arrangement, the reactants were preheated by internal heat recirculation and the conversion of CO 2 was enhanced by the catalyst surface reaction. The temperature measurement at the axial position and infrared thermograph observation on the catalyst packed-bed indicated that the peak temperature could be stabilized and held at the interface of the PM and catalyst bed, which significantly improved the propagation and stability of the flame. This was helpful to the improvement of both thermal wave transfer and internal heat recirculation. [ABSTRACT FROM AUTHOR]