Efficiency, Economic and Environmental Impact Assessment of a Newly Developed Rail Engine using Hydrogen and Other Sustainable Fuel Blends

Locomotives still use antiqued engines, such as internal combustion engines operated by fossil fuels which cause global warming due to their significant emissions. This paper continues investigating the newly hybridized locomotive engine containing a gas turbine system, solid oxide fuel cell system, energy saving system, and on-board hydrogen production system. This new engine is operated using five fuel blends composed of five alternative fuels such as hydrogen, methane, methanol, ethanol, and dimethyl ether. The current investigation involves exergy analysis, exergo-economic analysis, and exergo-environmental analysis to assess the engine from three perspectives: efficiency/irreversibility, cost, and environmental impact. The study results show that the net power of this new engine is 4948.6 kW, and it has an exergetic efficiency of 62.7% according to the fuel and product principle. This engine weighs about 9 tons and costs about $10.2M, with a levelized cost rate of 147 $/h and 14.06 mPt/h of overall component-related environmental rate. The average overall specific fuel and product exergy costs are about 37 $/GJ and 60 $/GJ, and the minimum values are 13.3 $/GJ and 21.8 $/GJ using methane and hydrogen blend, respectively. Also, the average overall specific fuel and product exergo-environmental impact are about 15 and 23 mPt/MJ, respectively. The on-board hydrogen production has an average exergy cost of 274 $/GJ and an environmental impact of 52 mPt/MJ. Hydrogen blended with methane or methanol is found to be more economic and has less environmental impact.