Hydrogen has the potential to support shipping’s transition to net zero emissions, but fundamental challenges linked to fuel energy density and infrastructure remain significant, according to Lloyd’s Register (LR).

In its Fuel for Thought: Hydrogen report, LR highlights hydrogen’s low energy density by volume as a key constraint for ship design and operations.

Even in liquefied form, hydrogen contains far less energy density on a volumetric basis than other marine fuels.

The report notes that liquid hydrogen delivers around 8.49 megajoules (MJ) per liter, compared with about 21.6 MJ per liter for LNG, meaning vessels require substantially larger fuel tanks to achieve comparable range.

This tank space penalty can reduce cargo capacity or necessitate more frequent bunkering, limiting hydrogen’s practicality for long-distance voyages.

As a result, LR says most current hydrogen projects are focused on short-sea and coastal vessels with predictable routes and regular refuelling opportunities.

For instance, Samskip‘s two hydrogen fuel cell powered ships are set to be operational next year. 

Infrastructure presents a parallel challenge.

LR notes that hydrogen bunkering facilities are still limited and will require significant capital investment due to the need for specialized storage, handling and transportation systems.

The report also points out that low-emissions hydrogen accounted for less than 1% of global hydrogen production in 2023, raising concerns over near-term fuel availability for shipping.

While early projects, often supported by state funding, are helping to build operational experience, LR concludes that stronger carbon pricing and broader decarbonisation policies will be critical to improving hydrogen’s commercial viability and enabling wider adoption in the shipping sector.

“The greatest challenge for hydrogen in shipping is its commercial viability, which will ultimately
be dictated by the world’s commitment to decarbonisation,” the report states.

The report can be downloaded from here.