Hydrogen retrofitting for regional freight Decarbonization: vehicle-level feasibility and energy system implications

Regional freight transport remains difficult to decarbonize due to high daily mileage, operational variability, and limited charging flexibility, which constrain the suitability of battery electric vehicles (BEVs) for medium- and long-distance delivery missions. This study proposes a multi-scale framework to assess hydrogen retrofitting of existing diesel light commercial vehicles (LCVs) as a decarbonization strategy for regional freight transport. A real-world case study based on four representative delivery routes in the Rome metropolitan area is used to evaluate retrofit feasibility using commercially available fuel cell systems, lithium-ion batteries, and 350 bar hydrogen storage. The proposed fuel cell hybrid electric vehicle (FCHEV) achieves an estimated operational range exceeding 290 km while reducing capital expenditure (CAPEX) by approximately 40–50% compared with new hydrogen-powered LCVs. Vehicle-level results are extended to estimate fleet-scale hydrogen demand, electricity requirements, and infrastructure implications, providing decision support for freight fleet transition and regional transport decarbonization.