Natural gas as a transitional solution for railway powering systems: Environmental and economic assessment of a fuel cell based powering system

摘要

This study presents a comprehensive environmental impact and economic assessment of the use of natural gas in potentially cleaner locomotives. An integrated direct methane-solid oxide fuel cell powering system is proposed and analyzed using energy and exergy methods. The system reaches the optimum energy and exergy efficiencies of 85.8% and 83.3%, respectively. Comparing the operation of this integrated system to a currently used diesel-electric engine for an intercity passenger locomotive duty cycle, the use of methane in a solid oxide fuel cell powering system reduces CO2 emissions by 58.4%, and fuel costs drop by a factor of 3.4. In general, a total of 10.6% increase in power production by the cascaded Rankine cycles helps reduce the CO2 emissions by 4.4%. As a result, the use of natural gas in rail transportation has clear and significant environmental and economic advantages over diesel. Also, the implementation of solid oxide fuel cell-based powering systems is justified environmentally and economically, and future researchers should build prototypes for demonstration purposes of future clean locomotives.