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.