Maritime hydrogen power and transport
The shipping industry contributes 3% of the total global greenhouse gas emissions, a significant portion of which can be attributed to shipping hubs. The port of Rotterdam, for example, produced 22.4 million tonnes of CO2 in 2020. While improvements to operational and system efficiency are decreasing these numbers, maritime hydrogen power is a renewable power source which the shipping industry clearly needs.
Renewable power source options
The search for a renewable power source has been complicated by the substantial energy requirements of large shipping vessels: batteries are too heavy and have limited range, and biofuels are not yet ready to be used for sustainable large scale production. The ideal solution seems to be hydrogen, as its high energy density makes it viable for long distance commercial transport.
Hydrogen powered shipping projects underway
The first hydrogen shipping projects are underway, with smaller hydrogen powered passenger ferries already in operation. In 2017, Hydroville launched a hybrid hydrogen-diesel ferry in Belgium; and in 2021, Scotland plans to introduce a similar ferry as part of the HyDIME project. These small scale projects provide a proof of concept for the use of hydrogen in marine transport, and as hydrogen technology advances and fuel cell output increases, projects are beginning to increase in scale.
The Flagships project is preparing to deploy the first hydrogen-powered commercial cargo vessel on the river Seine in September 2021. The project received €5mil in 2018 as part of the Horizon Research and Innovation Program in order to deploy hydrogen vessels in France and Norway. This Compagnie Fluvial de Transport funded vessel will be powered by compressed green hydrogen produced using electrolysis. This will provide a zero emissions alternative to traditional oil and diesel powered shipping.
In 2022, Norway’s Norled and Linde plan to release the MF Hydra ferry as the first green hydrogen powered car and passenger ferry.
By 2027, DFDS is aiming to produce a hydrogen powered ferry, the Europa Seaways vessel, to make the two day journey between Copenhagen and Oslo – a trip which normally burns 35 tons of oil. Europa Seaways is designed to carry 1800 passengers and 120 trucks or 380 cars, and will require a 23 MW output. Providing such power will be quite the challenge as fuel cells currently output 1-5 MW at most. While work is being done to achieve these goals, it may still be a while before hydrogen-powered long haul cargo ships become truly viable.
More challenges of hydrogen powered shipping
Storage is another major hurdle impeding the scaled implementation of the hydrogen economy. Long voyages require substantial amounts of hydrogen, which must be stored in liquid form at very high pressures and low temperatures. Technological improvements will be necessary to compress hydrogen efficiently.
There is also concern about the space requirements for hydrogen storage, although an ICCT study found that today’s hydrogen shipping technology is sufficient to power 43% of current voyages between the US and China with no compromised cargo space or need to stop and refuel. The majority of the other 57% of voyages could be made with only slight adjustments to fuel capacity or operations.
Using commercial shipping for hydrogen transport
As hydrogen production scales up, pipelines, trucks, and tankers will be required to transport the hydrogen to where it is needed. A prototype for one such liquid hydrogen transport ship, the Suiso Frontier, was developed in 2019 to transport hydrogen from the Port of Hastings, Australia to Kobe, Japan; shipping will begin in 2021. The Suiso Frontier carries liquid hydrogen in a 2500 m3 spherical tank at the remarkably low temperature of -253°C. Storing hydrogen at such a low temperature and high quantity has required technological redesigns of pre-existing liquid natural gas transport systems.
Hydrogen storage methods
Additional hydrogen storage methods are being researched, including storage as ammonia or sodium borohydride. These alternatives come with their own issues though, including the high energy demand of conversion to/from hydrogen, unwanted by-products, and toxicity concerns.
The safety of hydrogen as a fuel source is also a concern as hydrogen is highly flammable, odorless, colorless, and prone to leaking. This is clearly not the safest combination of features, and presents new handling challenges that are not faced when using oil based products. But several industries have successfully used hydrogen over the past several years, and there are established best practices for storing hydrogen. A major hurdle will be introducing hydrogen technology into new industries, where people will have to be trained to safely implement and use hydrogen.
Once the challenges associated with the hydrogen economy are overcome, maritime hydrogen power is likely to provide the decarbonisation solution that the energy intensive commercial transport industry is looking for.