Electrofuels for Road, Rail, Maritime, and Aviation Sectors: Assessing the Potential Challenges and Opportunities for...

Electrofuels (e-fuels) offer a decarbonization pathway for the hard-to-abate transport sectors of aviation, maritime, rail, and heavy-duty road transport by exploiting existing fuel infrastructure while eliminating fossil carbon emissions. Despite this advantage, commercial deployment remains constrained by prohibitive production costs (currently €3-6/L for e-diesel, €2-5/L for e-methanol), intensive energy requirements (∼50 kWh renewable electricity per liter), and systemic upscaling barriers including feedstock availability and carbon source purity. We critically examine sector-specific deployment potential, identifying aviation and maritime as priority markets where electrification alternatives remain limited while highlighting hybrid architectures (e-fuel/electric synergies) for rail and road applications. This review synthesizes recent technological advances demonstrating pathway efficiency improvements up to 70% through process intensification and advanced catalytic systems, notably CO₂ hydrogenation selectivity exceeding 80% for e-kerosene synthesis. Life cycle assessments indicate emission reductions of 75-90% relative to fossil-fuel counterparts, contingent on fully renewable energy inputs. Economic modeling projects cost parity trajectories toward €1.5-3.0/L by 2030, driven by renewable energy scale-up and learning-curve effects in electrolyzer and synthesis technologies. Policy analysis highlights the necessity of carbon pricing mechanisms, renewable fuel mandates, and targeted R&D funding to derisk investment and accelerate market formation. Finally, we explain critical research gaps in large-scale system integration, sustainable carbon sourcing, and life cycle sustainability assessment methodologies. By addressing these multidimensional challenges, e-fuels can transition from niche demonstration to commercially viable bridge technologies on the path to fully sustainable transport ecosystems.