Michael Barnard’s maritime energy pathway shows fossil fuels make up 40% of freight tonnage but provide roughly half of shipping’s energy. Bulk trades such as coal, oil and gas travel long distances, so their decline cuts a disproportionate share of ton‑kilometres and bunker fuel demand. The analysis shifts focus from replacing a fuel pool to shrinking the work ships perform.

A recent Nature Energy paper quantified the electrifiable wedge in short‑sea routes, finding a sizable share of maritime energy could shift to batteries when route structure, ship class and operating patterns are considered. Inland vessels, ferries and coastal services already benefit from shore power and terminal charging, making them prime candidates for full‑electric or hybrid solutions. This reshapes the residual fuel question.

With bulk fossil trades receding, only niche voyages will still need energy‑dense liquids such as biomethanol or bio‑diesel. Hybrid ships can use these fuels as range extenders while the majority of short‑haul traffic runs on electricity. The sector’s decarbonization path therefore begins by eliminating long‑haul fossil work, not by finding a universal substitute. Policy frameworks must reflect this reduced denominator to guide fuel incentives.