Although none of the ZEVs are estimated to be more competitive than conventional shipping by 2030, the technology options are evolving rapidly and it is possible that, over the next 10 years, the gap could reduce even further than this study estimates. If this gap does not close then there may be a need for regulatory intervention in the near future, to drive the viability compared to conventional fossil fuels.

This new report assesses seven technology options for ZEVs, applied to five different case study ship types across three different regulatory and economic scenarios. These options consist of various combinations of battery, synthetic fuels and biofuel for the onboard storage of energy, coupled with either a fuel cell and motor, internal combustion engine; or a motor for the conversion of that energy store into the mechanical and electrical energy required for propulsion and auxiliary services.

The costs of some of the components considered: fuel cells, batteries and hydrogen storage could all reduce significantly, especially if they become important components of another sector’s decarbonisation, or if action taken during shipping’s transition assists with the technology’s development.

For those in shipping with niche access to a low-cost supply of zero-emission fuel or energy sources, or an ability to pass on a voyage cost premium to a supply chain that values zero-emission services, the gap may already be closed, the study finds.

From preliminary conversations with shipowners, it was clear that the key considerations would be around wanting options that were viable at a moderate carbon price (e.g. $50/tonne CO2) and without too great an increase to the capital cost of the ship. It was also clear that the impact of the CO2 emissions must not just be moved upstream, to the electricity generation or fuel production process.

None of the zero-emission options in their current specifications completely satisfy the shipowner requirements, with the most significant gap identified being on voyage (fuel) costs, the study adds.

Katharine Palmer, LR’s Global Sustainability Manager, said: “By assessing different decarbonisation options for different ship types, we identify the drivers that need to be in place to make them a competitive solution and we aim to show the opportunity for a successful and low-cost decarbonisation pathway for shipping.”

The study can be downloaded here.