H2 shipping approaches viability in ‘niche’ circumstances
Short-haul, scheduled shipping routes will likely be first to switch to hydrogen-powered vessels
Low-capacity fuel cells, inadequate H2 production and high costs threaten to prevent hydrogen from becoming a viable maritime fuel—but industry experts remain confident these problems can be resolved and, for very limited applications, vessels are already being considered.
Shipping typically uses heavy fuel oil or diesel. But the International Maritime Organization aims to cut the industry’s greenhouse gas emissions by at least 50pc by 2050 versus 2008 levels by switching to renewable energy, including hydrogen.
Carbon pricing will be crucial in persuading the sector to quit fossil fuels, and the EU is poised to include shipping in its emissions trading system from 2021. This would substantially raise marine fuel costs, but hydrogen and fuel cell prices should steadily decline over the next decades.
“Zero-emission shipping is possible in technological and financial terms” Godjevac, Future Proof Shipping
But for now, fuel cells’ “power train and fuel are still far too expensive”, and international technical standards remain absent, industry association Hydrogen Europe warns.
In terms of total cost of ownership, running a container ship on hydrogen would cost nearly six times as much as running the same vessel on low-sulphur fuel, a US government report estimates.
In addition, the maximum power capacity of hydrogen fuel cells is around 6MW, making them unsuitable for container ships, which need an average of 28MW, says Laurent Debart, a project shipbroker at BRS Brokers in Geneva. Ferries and cargo ships, which require 2-10MW, are therefore a much more viable prospect.
Transporting hydrogen is also expensive. Experts envisage siting small-scale production facilities near individual ports to minimise costs until demand is sufficient to justify building larger plants that will supply multiple ports. Eventually, green hydrogen will be imported from regions with cheap, abundant renewable energy such as the Middle East.
“It is important to start with a localised infrastructure. It is not like we are going to see all the ships moving to hydrogen propulsion. It will be one by one,” says Debart.
High-yield, short-haul ferries and other vessels serving set routes, for example supply ships serving offshore wind farms, offer promise.
“If we can start with these small niche trades around the port, we can slowly build up the infrastructure around small ships and as we build up this infrastructure and the price of hydrogen and fuel cells goes down then slowly we will see the bigger ships getting involved, and by then the infrastructure will already exist,” adds Debart.
In Norway, cement manufacturer HeidelbergCement and agricultural cooperative Felleskjopet Agri have launched a tender for a third party to build a zero-emission vessel they guarantee to operate for 20 years. Gravel will be transported from Rogaland on Norway’s southwest coast to Oslofjord, while on the return journey the ship will carry grain. This arrangement almost eliminates ballast time, a major shipping cost.
“Zero-emission shipping is possible in technological and financial terms,” says Milinko Godjevac, senior integration adviser at Netherlands’ Future Proof Shipping, which is retrofitting an inland cargo vessel to run on hydrogen fuel cells.
99pc – China-US voyages that could be powered by hydrogen
According to a 2020 study by independent non-profit the International Council on Clean Transportation, 99pc of voyages between China’s River Delta and the US’ San Pedro Bay could be powered by hydrogen fuels with “only minor changes to ships’ fuel capacity or operations”.
This could be achieved by allocating 5pc of cargo space to hydrogen storage or adding one port call to refuel en route. The report claims 43pc of ships travelling along this route—part of the trans-Pacific corridor, which accounts nearly half of global container shipments—could complete the entire journey without either of these steps.
Another option is to first transition to dual-fuel vessels. The Port of Antwerp has commissioned Belgium’s CMB Tech to convert a tugboat to run on a mix of diesel and hydrogen. The vessel will house nearly 400 cylinders holding a combined 405kg of hydrogen at 250 bar pressure in its below-deck aft compartment.
CMB Tech claims hydrogen combustion engines outperform hydrogen fuel cells at higher loads, noting that, in practice, the efficiency of fuel cells is around 45-50pc—within 1-2pc of diesel’s rate.
“We can achieve a 50pc plus reduction in CO2 on existing engines without a significant impact on thermal efficiency,” says Trevor Jasper, CMB Tech’s engineering manager for low-carbon technologies. “Right now, hydrogen in a combustion engine is a very cost effective and smart way to go for decarbonising transport.”