Comparative efficiency and environmental impact assessments of a hydrogen assisted hybrid locomotive

•A new hydrogen assisted locomotive powering system is proposed.•The system is assessed thermodynamically and environmentally.•Comparative evaluations are performed between the proposed and the conventional diesel system.

The integration of more environmentally benign fuel options for mass transportation applications is a critical research initiative, particularly those that support and further development toward a hydrogen economy, a key target for future sustainability. The thermodynamic and environmental performances of a hydrogen assisted hybrid locomotive with ammonia-diesel co-fueling are comprehensively assessed through energy and exergy analyses, and impact assessment. Onboard hydrogen production via thermal ammonia decomposition (cracking) utilizes exhaust gases as a heat source, reducing the total diesel fuel consumption and increasing energy utilization of the fuel burned in the locomotive prime mover engine. The hybrid system performance is compared against a conventional diesel-electric locomotive through energy and exergy efficiencies, fuel consumption, and environmental impact to evaluate the viability of the hybrid locomotive as a clean rail transportation option.