This study investigates the prospects for implementing hydrogen mobility in Bulgaria within the broader context of transport decarbonization. Using a three-dimensional framework—policy, technology, and geography—it combines analysis of European and national strategic documents, technological feasibility assessment, and a pilot case study in the city of Ruse. The pilot scenario includes a regional hydrogen ecosystem with a photovoltaic-powered electrolyzer, two refueling stations, deployment of 20 hydrogen buses, and retrofitting of a river vessel with fuel cell propulsion. Results indicate that hydrogen technologies can significantly reduce transport-related emissions, particularly where battery-electric solutions face operational constraints. Total Cost of Ownership (TCO) analysis shows that hydrogen buses remain more expensive than diesel or battery-electric alternatives under current conditions, even with locally produced green hydrogen. Sensitivity analysis demonstrates that cost competitiveness may be achieved after 2030 with large-scale investments, policy support, and reduced hydrogen prices. The study highlights the importance of coherent national strategies, public–private partnerships, and targeted financial instruments to enable sustainable integration of hydrogen in urban and river transport systems.
Pencheva et al. (2026) studied this question.