Fuel cells are one of the most promising solutions for reducing CO2 and GHG emissions in the maritime sector, according to panelists at a recent Riviera Maritime Media webinar
Hydrogen fuel cells have a promising future in the maritime sector, but several key technical hurdles need to be addressed, according to presenters at Riviera Maritime Media’s Fuel Cells: addressing the key technical challenges webinar. At the third in a series of webinars held during Maritime Hybrid, Electric and Fuel Cells Webinar Week in June, attendees heard from premier partners Ulstein Design & Solutions product manager Ko Stroo, GE Power Conversion senior sales manager for passenger vessels Renaud Cornu and Nedstack chief commercial officer Roel Van de Pas.
The expert panellists spoke about the safety and reliability of hydrogen storage and fuel-cell systems, their layout within newbuildings, how to produce robust fuel-cell technologies for maritime applications, the power requirements for different classes of ships and fuel-cell refurbishing and recycling.
They outlined a zero-emissions future for shipping that all three said could begin sooner than many in the industry expect, if the will is there.
“Hydrogen is the only solution for zero emissions”
But to implement the hydrogen fuel-cell technology that could hasten the end of emissions, there are still several hurdles to overcome, not least of which is the shortage and bunkering infrastructure required to support hydrogen.
Mr Stroo said he expects full-ship systems will be installed on offshore support vessels and ships employed for shortsea voyages, before eventually being installed on other ship types.
“There is the possibility for deepsea hydrogen-fuelled ships, and not just for shortsea or smaller vessels,” Mr Stroo said. “To do this, we need to design the ship around the fuel cell.”
Ulstein has developed a ship design for a zero-emissions offshore vessel as a case study with hydrogen propulsion technology on board. Ulstein SX190 is a 99-m, 5,000-dwt offshore vessel equipped to support hydrocarbon and renewable energy projects.
When it originally unveiled the design for the dynamic positioning class 2-capable Ulstein SX190 design in January, Ulstein Design said would have a total installed power of 7.5 MW, of which 2 MW would be generated by a fuel-cell power system, typically Nedstack Proton Exchange Membrane (PEM) fuel cells, which are located in a separate, second engineroom.
PEM fuel cells convert hydrogen and air into electric power, heat and water and produce no harmful emissions in the process. Nedstack fuel-cell systems have already been built and proven in the multi-megawatt power ranges and have now been marinised to meet the requirements of the marine industry, including class requirements and supply chains.
Mr Stroo explained how Ulstein overcame the challenges of fuelling this vessel. “We selected a flexible, containerised gas storage system on the aft deck. The current capacity of this storage system limits the range to four to five days in zero-emissions mode, but it allows the vessel to be independent of any hydrogen bunkering facilities. This already-available solution bridges the gap towards future hydrogen regulations and infrastructure,” Mr Stroo said.
In his presentation, he outlined a roadmap to introducing hydrogen-fuelled ships. The first step would be to swap onboard gas storage for liquid hydrogen containers. “Cryogenic liquid hydrogen containers will become commercially available in the coming years, and would take the range to two weeks, without any modifications to the vessel, and maintaining the bunker flexibility of a containerised system,” said Mr Stroo.
“When port bunker facilities for liquid hydrogen become available, the large project stores under the main deck can be used to install two large liquid hydrogen storage tanks,” he added. This extends zero-emissions endurance to a month, while keeping the full work deck available for offshore operations.
“The final step will be a vessel fully powered by hydrogen, but this is only feasible when liquid hydrogen is available worldwide,” he said. “Until then, fuel flexibility will be a necessity in the transition towards a hydrogen economy.”
Mr Cornu expects ships with hydrogen fuel-cell technology will be built in the future to ensure the shipping industry can meet IMO’s goal for 50% cuts in carbon emissions in the long term. “Hydrogen is the only solution for zero emissions,” he said during the webinar. “Liquefied hydrogen is the way to go for shipping in the future.” This future will start with fuel-cell power installations of around 2 MW capacity with power drive train, transformer and power management systems.
The next stage of adoption requires testing larger fuel cells, with a 3-MW cell under development, and a range of hybrid solutions, said Mr Cornu. He said future developments in hydrogen-fuelled ships will not involve retrofits but will require new designs and constructions.
“By combining battery and fuel-cell strength, zero-emissions shipping can already be achieved”
“We need technology to be workable, so we need to start from a blank sheet to go fully hydrogen or for a hybrid system,” said Mr Cornu.
GE has an exclusive partnership with Nedstack for applying hydrogen fuel-cell technology in the maritime sector. Nedstack’s Mr Van de Pas anticipates future ships will have hybrid systems on board with hydrogen fuel cells operating alongside batteries or conventional diesel-electric systems.
“Ships would not need to be zero emissions all of the time,” he said. “By combining battery and fuel-cell strength, zero-emissions shipping can already be achieved.”
Mr Van de Pas said fuel-cell technology is available at 2-MW capacity and proven in other settings. “Fuel cells were placed on board ships almost a decade ago, and we have the first stationary MW fuel-cell power plants,” he explained.
“Strong safety concepts have been developed and we have class acceptance, so now is the time to demonstrate deploying this technology.” DNV GL certified Nedstack’s fuel-cell concept in 2012 and MARIN tested its seaworthiness in 2018-2020. Now there needs to be a pilot project with a ship operator.
“Only in partnership with shipowners can we move to deploying zero-emission shipping solutions,” Mr Van de Pas concluded.
Watch the Fuel Cells: addressing the key technical challenges webinar in our webinar library