Powering European ships with batteries, hydrogen or ammonia will decarbonise the fleet and require only half the amount of renewable electricity than less efficient solutions like synthetic methane or synthetic diesel will need.

This was revealed by sustainable transport group Transport & Environment (T&E), which has published a Roadmap to Decarbonising European Shipping. In its 2050 Decarbonisation Strategy, to be published on 28 November, the EU must set out how it will end the use of fossil fuels in shipping, including marine fuel oil and liquified natural gas (LNG).

Combination of Batteries, Hydrogen and Ammonia

Battery powered ships offer the most efficient and immediate solution to decarbonise short sea voyages within the EU. Longer journeys will ultimately require liquid hydrogen and liquid ammonia produced with zero-emission electricity.

Powering ships calling at EU ports with a combination of the three would require around 25% additional renewable electricity compared to total EU electricity production today, the analysis finds. This is a considerable amount, but still half of what is required by other options like synthetic methane or synthetic diesel.

Zero-emission Shipping Strategy Can Give EU companies an Edge

Shipping emits 3% of global CO2 and would be the sixth biggest emitter after Japan if it were a country. EU-related shipping is responsible for about one-fifth of these emissions. The UN’s International Maritime Organization (IMO) has just agreed a goal to reduce shipping emissions by at least fifty per cent by 2050, but there are no plans to reach zero emissions.

Faig Abbasov, shipping officer at T&E, said: 'Shipping is the neglected stepchild of EU climate policy. We need progress at an international level coupled with practical steps in Europe such as investment in both shore-side charging stations and the production and bunkering infrastructure needed for hydrogen. A zero-emission shipping strategy in the EU would help cut pollution but also give European companies an edge in what will be some of the most important technologies of the future.'

Synthetic Methane and Diesel Have Drawbacks

Often touted solutions such as synthetic methane and synthetic diesel have major drawbacks, the analysis also finds. Their apparent physical properties are similar to their fossil equivalents, making it difficult for authorities to distinguish them and enforce their use. They also require far higher amounts of renewable energy than batteries, hydrogen and ammonia. Moreover, synthetic methane suffers from methane leakage and slip – as does fossil LNG.

Gas Infrastructure Could Lock EU Countries into Using LNG

T&E said that further investment in gas bunkering infrastructure would lock EU countries into using LNG, which does not offer a path to decarbonisation and in some cases is worse than other fossil fuels. Such investment would also open the way for synthetic methane. The small amounts of biofuels that can be produced sustainably would be better used in sectors which have no alternatives to using liquid fuels, such as aviation.

The full Roadmap to Decarbonising European Shipping can be downloaded from the T&E website.